PUBLICATIONS
BGC is dedicated to furthering the study of the innovations in the industries we serve. As part of our team’s professional development, BGC experts co-author articles and technical publications and present many of them at industry conferences. Recent publications by BGC staff are listed below. To request a copy of a publication, please reach out to our BGC Library team at library@bgcengineering.ca. Due to copyright restrictions, we may not be able to provide copies of all the publications listed below.
2022
Lato, Matthew; Lau, Carie-Ann
A Coordinated Response to the November 2021 Atmospheric Rivers on Infrastructure in British Columbia Workshop
2022.
@workshop{Presentation1,
title = {A Coordinated Response to the November 2021 Atmospheric Rivers on Infrastructure in British Columbia},
author = {Matthew Lato and Carie-Ann Lau},
url = {https://www.usgs.gov/media/videos/coordinated-response-november-2021-atmospheric-rivers-infrastructure-british-columbia},
year = {2022},
date = {2022-12-30},
urldate = {2022-12-30},
abstract = {A USGS Landslide Hazards Seminar.
The BC floods occurred in the traditional lands of First Nations and the social implications of the flood were amplified by legacies of the Indian Act. BC experienced several significant weather events in 2021. Southern British Columbia and Northwestern Washington experienced a significant atmospheric river event from November 13 to 15, 2021.},
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A USGS Landslide Hazards Seminar.
The BC floods occurred in the traditional lands of First Nations and the social implications of the flood were amplified by legacies of the Indian Act. BC experienced several significant weather events in 2021. Southern British Columbia and Northwestern Washington experienced a significant atmospheric river event from November 13 to 15, 2021.
The BC floods occurred in the traditional lands of First Nations and the social implications of the flood were amplified by legacies of the Indian Act. BC experienced several significant weather events in 2021. Southern British Columbia and Northwestern Washington experienced a significant atmospheric river event from November 13 to 15, 2021.
van Veen, Megan; Funk, Andrew; Fish, Colleen; Porter, Mike
A Landslide Velocity Database for the Site C Reservoir in Northeastern British Columbia Conference
GeoCalgary, 2022.
@conference{Conference1,
title = {A Landslide Velocity Database for the Site C Reservoir in Northeastern British Columbia},
author = {Megan van Veen and Andrew Funk and Colleen Fish and Mike Porter},
year = {2022},
date = {2022-12-28},
urldate = {2022-12-28},
booktitle = {GeoCalgary},
abstract = {The modern Peace River Valley in British Columbia contains an abundance of landslides with volumes ranging from tens of cubic metres to more than 10 million cubic metres. Landslide types in this region range from shallow slides in overburden to deep seated slides in clay shale bedrock, and often involve multi-level, complex landslide mechanisms. A landslide inventory for this region was updated by BGC in 2021 and 2022 to assign qualitative landslide behaviour types to each landslide, which reflect the dominant mode of landslide movement, long-term mean annual displacement rates, and the estimated relative frequency of faster movements. Airborne lidar change detection between 2006, 2015, 2019, and 2021 and satellite InSAR data from 2020 and 2021, coupled with select field observations, were used to estimate the velocity of landslides over each incremental date range. The velocity distributions were compared to the long-term average probability distributions (limiting state vectors) proposed for each behaviour type, which have been used to define transition matrices for Markov chain modelling of landslide velocities.},
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pubstate = {published},
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The modern Peace River Valley in British Columbia contains an abundance of landslides with volumes ranging from tens of cubic metres to more than 10 million cubic metres. Landslide types in this region range from shallow slides in overburden to deep seated slides in clay shale bedrock, and often involve multi-level, complex landslide mechanisms. A landslide inventory for this region was updated by BGC in 2021 and 2022 to assign qualitative landslide behaviour types to each landslide, which reflect the dominant mode of landslide movement, long-term mean annual displacement rates, and the estimated relative frequency of faster movements. Airborne lidar change detection between 2006, 2015, 2019, and 2021 and satellite InSAR data from 2020 and 2021, coupled with select field observations, were used to estimate the velocity of landslides over each incremental date range. The velocity distributions were compared to the long-term average probability distributions (limiting state vectors) proposed for each behaviour type, which have been used to define transition matrices for Markov chain modelling of landslide velocities.
Collier-Pandya, Beatrice; McDougall, Scott; Mitchell, Andrew; van Veen, Megan; Porter, Mike; Mulligan, Ryan; van Gassen, Wim
A Review of Existing Reservoir Shoreline Erosion Prediction and Monitoring Methods Conference
Proceedings of the 8th Canadian Conference on Geotechnique and Natural Hazards: Innovative geoscience for tomorrow, 2022.
@conference{Conference1,
title = {A Review of Existing Reservoir Shoreline Erosion Prediction and Monitoring Methods },
author = {Beatrice Collier-Pandya and Scott McDougall and Andrew Mitchell and Megan van Veen and Mike Porter and Ryan Mulligan and Wim van Gassen},
year = {2022},
date = {2022-12-26},
urldate = {2022-12-30},
booktitle = {Proceedings of the 8th Canadian Conference on Geotechnique and Natural Hazards: Innovative geoscience for tomorrow},
abstract = {With ongoing efforts to transition energy usage to renewable sources, new hydroelectric projects are being considered. Particularly, a new hydroelectric project on the Peace River near Fort St. John, British Columbia is under construction. A detailed geotechnical assessment was undertaken in 2012 to generate preliminary impact lines that delineate potential stability, erosion, and flood hazard areas around the future reservoir. A construction headpond currently formed by river diversion provides site-specific data to potentially improve upon initial shoreline erosion predictions. Predicting shoreline erosion around reservoirs associated with new hydroelectric projects provides a challenge due to their lack of historical erosion. The wave processes driving erosion are also fetch-limited, and therefore some sites have larger waves depending on wind direction and fetch across the reservoir. Several shoreline erosion prediction and monitoring methods are compared and discussed. Future research will focus on improving material-specific erosion coefficients and gathering wave data to calibrate wind-generated wave models.},
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With ongoing efforts to transition energy usage to renewable sources, new hydroelectric projects are being considered. Particularly, a new hydroelectric project on the Peace River near Fort St. John, British Columbia is under construction. A detailed geotechnical assessment was undertaken in 2012 to generate preliminary impact lines that delineate potential stability, erosion, and flood hazard areas around the future reservoir. A construction headpond currently formed by river diversion provides site-specific data to potentially improve upon initial shoreline erosion predictions. Predicting shoreline erosion around reservoirs associated with new hydroelectric projects provides a challenge due to their lack of historical erosion. The wave processes driving erosion are also fetch-limited, and therefore some sites have larger waves depending on wind direction and fetch across the reservoir. Several shoreline erosion prediction and monitoring methods are compared and discussed. Future research will focus on improving material-specific erosion coefficients and gathering wave data to calibrate wind-generated wave models.
Donati, Davide; Rabus, Bernhard; Engelbrecht, Jeanine; Stead, Doug; Clague, John; Francioni, Mirko
A Robust SAR Speckle Tracking Workflow for Measuring and Interpreting the 3D Surface Displacement of Landslides Journal Article
In: Remote Sensing, vol. 13, no. 15, 2022.
@article{journal1,
title = {A Robust SAR Speckle Tracking Workflow for Measuring and Interpreting the 3D Surface Displacement of Landslides},
author = {Davide Donati and Bernhard Rabus and Jeanine Engelbrecht and Doug Stead and John Clague and Mirko Francioni},
doi = {10.3390/rs13153048},
year = {2022},
date = {2022-12-25},
urldate = {2022-12-29},
journal = {Remote Sensing},
volume = {13},
number = {15},
abstract = {We present a workflow for investigating large, slow-moving landslides which combines the synthetic aperture radar (SAR) technique, GIS post-processing, and airborne laser scanning (ALS), and apply it to Fels landslide in Alaska, US. First, we exploit a speckle tracking (ST) approach to derive the easting, northing, and vertical components of the displacement vectors across the rock slope for two five-year windows, 2010–2015 and 2015–2020. Then, we perform post-processing in a GIS environment to derive displacement magnitude, trend, and plunge maps of the landslide area. Finally, we compare the ST-derived displacement data with structural lineament maps and profiles extracted from the ALS dataset. Relying on remotely sensed data, we estimate that the thickness of the slide mass is more than 100 m and displacements occur through a combination of slumping at the toe and planar sliding in the central and upper slope. Our approach provides information and interpretations that can assist in optimizing and planning fieldwork activities and site investigations at landslides in remote locations.},
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We present a workflow for investigating large, slow-moving landslides which combines the synthetic aperture radar (SAR) technique, GIS post-processing, and airborne laser scanning (ALS), and apply it to Fels landslide in Alaska, US. First, we exploit a speckle tracking (ST) approach to derive the easting, northing, and vertical components of the displacement vectors across the rock slope for two five-year windows, 2010–2015 and 2015–2020. Then, we perform post-processing in a GIS environment to derive displacement magnitude, trend, and plunge maps of the landslide area. Finally, we compare the ST-derived displacement data with structural lineament maps and profiles extracted from the ALS dataset. Relying on remotely sensed data, we estimate that the thickness of the slide mass is more than 100 m and displacements occur through a combination of slumping at the toe and planar sliding in the central and upper slope. Our approach provides information and interpretations that can assist in optimizing and planning fieldwork activities and site investigations at landslides in remote locations.
Strouth, Alex; LeSueur, Philip; McDougall, Scott
ALARP and Other Conditions for Tolerating Geohazard Risks Conference
Proceedings of the 8th Canadian Conference on Geotechnique and Natural Hazards: Innovative geoscience for tomorrow, 2022.
@conference{Conference1,
title = {ALARP and Other Conditions for Tolerating Geohazard Risks},
author = {Alex Strouth and Philip LeSueur and Scott McDougall},
year = {2022},
date = {2022-12-23},
urldate = {2022-12-28},
booktitle = {Proceedings of the 8th Canadian Conference on Geotechnique and Natural Hazards: Innovative geoscience for tomorrow},
pages = {639-646},
abstract = {Geohazard areas are commonly in the transitional ‘grey-zone’ between clearly safe enough and clearly unacceptable. Here, tolerance of geohazard risk tends to be conditional, meaning that the risk can be lived with if certain conditions are met. A commonly cited condition is that risk must be reduced until it is As Low As Reasonably Practicable (ALARP). However, inconsistent definitions of ALARP are in use, which has led to miscommunication and poor decisions. Rather than referencing ALARP as the default condition for tolerating risk, specific, clear, and achievable conditions should be applied. Conditions for tolerating geohazard risks could include keeping the risk under review, following good practice to manage risks, using available resources to reduce risk, applying cost-effective measures to reduce risk, or reducing risk until the cost of further risk reduction is grossly disproportionate to the benefit gained. Risk management decisions must also consider the costs of risk reduction, which extend beyond the price of mitigation structures.},
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Geohazard areas are commonly in the transitional ‘grey-zone’ between clearly safe enough and clearly unacceptable. Here, tolerance of geohazard risk tends to be conditional, meaning that the risk can be lived with if certain conditions are met. A commonly cited condition is that risk must be reduced until it is As Low As Reasonably Practicable (ALARP). However, inconsistent definitions of ALARP are in use, which has led to miscommunication and poor decisions. Rather than referencing ALARP as the default condition for tolerating risk, specific, clear, and achievable conditions should be applied. Conditions for tolerating geohazard risks could include keeping the risk under review, following good practice to manage risks, using available resources to reduce risk, applying cost-effective measures to reduce risk, or reducing risk until the cost of further risk reduction is grossly disproportionate to the benefit gained. Risk management decisions must also consider the costs of risk reduction, which extend beyond the price of mitigation structures.
Ahadi, M; da Silva, Ana Ferreira; Grover, Patrick; Lockwood, Kenneth
An Experimental Study on Scour Beneath Pipelines at River Crossings Conference
River Flow 2022, 11th International Conference on Fluvial Hydraulics, 2022.
@conference{Conference1,
title = {An Experimental Study on Scour Beneath Pipelines at River Crossings},
author = {M Ahadi and Ana Ferreira da Silva and Patrick Grover and Kenneth Lockwood},
year = {2022},
date = {2022-12-22},
urldate = {2022-12-27},
booktitle = {River Flow 2022, 11th International Conference on Fluvial Hydraulics},
abstract = {This paper deals with scour beneath pipelines, a topic that despite its practical sig-nificance, has so far been the object of relatively few studies. The paper presents the initial results of a laboratory study carried out under clearwater conditions. The experiments consist of a series of nine 40 min long tests to determine the scour and free surface profiles at the end of the tests, and involving different values of pipe clearance and flow depth. Additionally, a 240 min long test was carried out with the pipe embedded into the bed surface. This test enabled the detailed mon-itoring of the scour hole development, including the stage of the onset of scour. For the tests with either zero or positive clearance, the two existing predictors of equilibrium scour depth yield val-ues of scour depth comparable to the flow depth, which appears to be realistic. This study high-lights the greatest limitation of previous work, which consists in the fact that it neglects the anal-ysis of scour associated with embedded pipes, with the result that no methods are available to predict equilibrium scour depth for such cases. The fact that the depth of the scour hole can be much greater for embedded pipes than for suspended ones is also illustrated by this work.},
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pubstate = {published},
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This paper deals with scour beneath pipelines, a topic that despite its practical sig-nificance, has so far been the object of relatively few studies. The paper presents the initial results of a laboratory study carried out under clearwater conditions. The experiments consist of a series of nine 40 min long tests to determine the scour and free surface profiles at the end of the tests, and involving different values of pipe clearance and flow depth. Additionally, a 240 min long test was carried out with the pipe embedded into the bed surface. This test enabled the detailed mon-itoring of the scour hole development, including the stage of the onset of scour. For the tests with either zero or positive clearance, the two existing predictors of equilibrium scour depth yield val-ues of scour depth comparable to the flow depth, which appears to be realistic. This study high-lights the greatest limitation of previous work, which consists in the fact that it neglects the anal-ysis of scour associated with embedded pipes, with the result that no methods are available to predict equilibrium scour depth for such cases. The fact that the depth of the scour hole can be much greater for embedded pipes than for suspended ones is also illustrated by this work.
Porter, Mike; van Hove, Joel; Barlow, Pete
Analysis of Dynamic System Risks Where Pipelines Cross Slow-Moving Landslides Conference
International Pipeline Conference, 2022.
@conference{Conference1,
title = {Analysis of Dynamic System Risks Where Pipelines Cross Slow-Moving Landslides},
author = {Mike Porter and Joel van Hove and Pete Barlow},
year = {2022},
date = {2022-12-21},
urldate = {2022-12-21},
booktitle = {International Pipeline Conference},
abstract = {Pipelines are often constructed across dormant or normally slow-moving landslides. The potential for pipeline failure in response to landslide movement depends on several factors. These include the likelihoods of different landslide velocities being realized, the probabilities that movements physically impact the pipeline, the capacity of the pipeline to accommodate landslide displacements, and the ability of operators to detect and respond to deteriorating conditions. Each of these factors is difficult to predict but estimating the probabilities of landslide velocity transitions is particularly challenging. In this paper we review a conceptual approach to predict landslide velocity and displacement using Markov chains that combine geomorphic evidence of long-term landslide behaviour with current estimates or measurements of landslide velocity. A framework is proposed to combine time-dependent estimates of landslide displacement and the deterioration of pipeline strain capacity to estimate the probability of pipeline failure over time and in response to potential changes in landslide velocity. The expected efficacy of monitoring programs and trigger action response plans is accounted for in the vulnerability model.},
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pubstate = {published},
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Pipelines are often constructed across dormant or normally slow-moving landslides. The potential for pipeline failure in response to landslide movement depends on several factors. These include the likelihoods of different landslide velocities being realized, the probabilities that movements physically impact the pipeline, the capacity of the pipeline to accommodate landslide displacements, and the ability of operators to detect and respond to deteriorating conditions. Each of these factors is difficult to predict but estimating the probabilities of landslide velocity transitions is particularly challenging. In this paper we review a conceptual approach to predict landslide velocity and displacement using Markov chains that combine geomorphic evidence of long-term landslide behaviour with current estimates or measurements of landslide velocity. A framework is proposed to combine time-dependent estimates of landslide displacement and the deterioration of pipeline strain capacity to estimate the probability of pipeline failure over time and in response to potential changes in landslide velocity. The expected efficacy of monitoring programs and trigger action response plans is accounted for in the vulnerability model.
Nikakhtar, Leila; Zare, Shokrollah; Nasirabad, Hossein; Ferdosi, Benham
Application of ANN-PSO Algorithm Based on FDM Numerical Modelling for Back Analysis of EPB TBM Tunneling Parameters Journal Article
In: European Journal of Environmental and Civil Engineering, vol. 26, no. 8, pp. 3169-3186, 2022.
@article{article1,
title = {Application of ANN-PSO Algorithm Based on FDM Numerical Modelling for Back Analysis of EPB TBM Tunneling Parameters },
author = {Leila Nikakhtar and Shokrollah Zare and Hossein Nasirabad and Benham Ferdosi},
doi = {10.1080/19648189.2020.1795725},
year = {2022},
date = {2022-12-20},
urldate = {2022-12-24},
journal = {European Journal of Environmental and Civil Engineering},
volume = {26},
number = {8},
pages = {3169-3186},
abstract = {In this research, three- dimension finite difference method was applied to simulate the tunnel excavation by earth pressure balance (EPB) boring machine of Tehran Metro Line 7 tunnel in Iran. Sensitivity analysis and parameter identification was carried out by Morris Elementary Effect method to evaluate the relative sensitivity of model for each input parameter. Then, artificial neural network (ANN) was used as a meta model to predict model response for the dataset of selected sensitive parameters. For this purpose, 100 numerical simulation has carried that a database including 1500 data was compiled for using in ANN. Thereafter, PSO algorithm was employed as a parameter identification technique to find the optimized values of the parameters according to monitoring surface settlement. Also, after material identification, the same PSO-ANN algorithm was used to optimize operation parameter (face pressure). The results showed that ANN prediction and numerical simulation with initial set of parameters has more than 98% concordance with about 2.4% RMSE and 0.014 MAE for all dataset. The optimized parameters gained via back analysis enable the meta model to well predict the ground settlement in the about 15 seconds.},
keywords = {},
pubstate = {published},
tppubtype = {article}
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In this research, three- dimension finite difference method was applied to simulate the tunnel excavation by earth pressure balance (EPB) boring machine of Tehran Metro Line 7 tunnel in Iran. Sensitivity analysis and parameter identification was carried out by Morris Elementary Effect method to evaluate the relative sensitivity of model for each input parameter. Then, artificial neural network (ANN) was used as a meta model to predict model response for the dataset of selected sensitive parameters. For this purpose, 100 numerical simulation has carried that a database including 1500 data was compiled for using in ANN. Thereafter, PSO algorithm was employed as a parameter identification technique to find the optimized values of the parameters according to monitoring surface settlement. Also, after material identification, the same PSO-ANN algorithm was used to optimize operation parameter (face pressure). The results showed that ANN prediction and numerical simulation with initial set of parameters has more than 98% concordance with about 2.4% RMSE and 0.014 MAE for all dataset. The optimized parameters gained via back analysis enable the meta model to well predict the ground settlement in the about 15 seconds.
Newton, Sarah; van Hove, Joel; Porter, Mike; Ferris, Gerald
Assessing Geohazard Probability of Pipeline Failure: Lessons and Improvements From the Last 10 Years Conference
International Pipeline Conference, 2022.
@conference{Conference1,
title = {Assessing Geohazard Probability of Pipeline Failure: Lessons and Improvements From the Last 10 Years},
author = {Sarah Newton and Joel van Hove and Mike Porter and Gerald Ferris},
year = {2022},
date = {2022-12-17},
urldate = {2022-12-17},
booktitle = {International Pipeline Conference},
abstract = {Geohazards, consisting of geotechnical hazards where ground movements impact pipelines and hydrotechnical hazards where pipelines cross watercourses, can threaten pipeline integrity, causing leaks or ruptures. Given the vast geographies traversed by pipeline infrastructure, geohazard frequency can be high requiring triage of large inventories of identified geohazard sites. Since 2012, field screening probability of failure algorithms have been used to assess and prioritize geohazard threats to pipeline integrity. These algorithms were developed using empirical data from failure case histories, engineering judgement from geohazard professionals, and statistical rates of pipeline impact, exposure, and failure. When combined with consequences, the algorithms provide semi-quantitative risk assessments. The risk assessments are used to compare geohazard threats to other pipeline integrity threats to support cost-benefit decisions for pipeline operation. The algorithms have been applied to 243,000 sites on 440,000 km of oil and gas gathering, transmission, and distribution pipelines primarily in Canada and the United States. In this paper, lessons learned from applying probability of failure algorithms to geohazard sites over the past 10 years are shared. The algorithms have proved successful in that their use has allowed pipeline operators to focus their integrity management effort on higher probability of failure sites. Use of the algorithms also allows operators to reduce investment on low probability of failure geohazard crossings. For example, the probability of failure assessments provide justification for less frequent reinspection intervals of low probability of failure sites, while providing clear means of advocating for the need to mitigate and monitor high probability of failure geohazard sites. Over the past decade, recalibration of the algorithms has reduced conservatism in earlier versions. As well, advancements in data collection, storage, and quality assurance have been undertaken to improve accuracy. This paper describes the methods used to assess probability of failure for pipeline landslide and watercourse crossings. The use cases and limitations of the algorithms are also discussed.},
keywords = {},
pubstate = {published},
tppubtype = {conference}
}
Geohazards, consisting of geotechnical hazards where ground movements impact pipelines and hydrotechnical hazards where pipelines cross watercourses, can threaten pipeline integrity, causing leaks or ruptures. Given the vast geographies traversed by pipeline infrastructure, geohazard frequency can be high requiring triage of large inventories of identified geohazard sites. Since 2012, field screening probability of failure algorithms have been used to assess and prioritize geohazard threats to pipeline integrity. These algorithms were developed using empirical data from failure case histories, engineering judgement from geohazard professionals, and statistical rates of pipeline impact, exposure, and failure. When combined with consequences, the algorithms provide semi-quantitative risk assessments. The risk assessments are used to compare geohazard threats to other pipeline integrity threats to support cost-benefit decisions for pipeline operation. The algorithms have been applied to 243,000 sites on 440,000 km of oil and gas gathering, transmission, and distribution pipelines primarily in Canada and the United States. In this paper, lessons learned from applying probability of failure algorithms to geohazard sites over the past 10 years are shared. The algorithms have proved successful in that their use has allowed pipeline operators to focus their integrity management effort on higher probability of failure sites. Use of the algorithms also allows operators to reduce investment on low probability of failure geohazard crossings. For example, the probability of failure assessments provide justification for less frequent reinspection intervals of low probability of failure sites, while providing clear means of advocating for the need to mitigate and monitor high probability of failure geohazard sites. Over the past decade, recalibration of the algorithms has reduced conservatism in earlier versions. As well, advancements in data collection, storage, and quality assurance have been undertaken to improve accuracy. This paper describes the methods used to assess probability of failure for pipeline landslide and watercourse crossings. The use cases and limitations of the algorithms are also discussed.
Craddock, Raymond; Kennedy, Gavin; Jamieson, Rob; Keizer, Jonathan; Mohammed, Aaron; Kurylyk, Barret
Assessment of Groundwater Discharge Pathways in a Till-Dominated Coastal Aquifer Journal Article
In: Journal of Hydrology: Regional Studies, vol. 44, 2022.
@article{journal1,
title = {Assessment of Groundwater Discharge Pathways in a Till-Dominated Coastal Aquifer},
author = {Raymond Craddock and Gavin Kennedy and Rob Jamieson and Jonathan Keizer and Aaron Mohammed and Barret Kurylyk},
doi = {10.1016/j.ejrh.2022.101205},
year = {2022},
date = {2022-12-16},
urldate = {2022-12-16},
journal = {Journal of Hydrology: Regional Studies},
volume = {44},
abstract = {Study region
Mabou Harbour located in Cape Breton Island, Nova Scotia, Canada, is representative of the many natural harbours throughout the Maritime region of Canada as the surrounding landscape is overlain by glacial deposits, predominantly composed of glacial till.
Study focus
Understanding the pathways facilitating groundwater flow and associated solute transport to the ocean is key for developing conceptual hydrogeologic models for coastal watersheds and for informing coastal zone management. Most local-scale field and modelling submarine groundwater discharge (SGD) studies have been conducted in high-permeability formations given the likely importance of SGD in these coastal settings. This study investigates direct (SGD) and indirect (seaward stream baseflow) groundwater discharge from a till dominated coastal aquifer using a combination of field measurements (river flow and baseflow separation, seepage meter measurements, and water temperature analysis) and a calibrated 3D numerical groundwater flow model.
New hydrological insights for the region
Results show that seaward stream baseflow greatly exceeds direct SGD to the ocean on the scale of the full harbour watershed (96.1% vs. 3.9 of total groundwater discharge). Particle tracking shows that the vast majority of SGD originates in the subcatchment immediately surrounding the harbour with limited intermediate or regional flow. The shorter flow paths and residence times for direct SGD results in less opportunity for natural attenuation processes and may have implications for groundwater-borne contamination to this harbour.},
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pubstate = {published},
tppubtype = {article}
}
Study region
Mabou Harbour located in Cape Breton Island, Nova Scotia, Canada, is representative of the many natural harbours throughout the Maritime region of Canada as the surrounding landscape is overlain by glacial deposits, predominantly composed of glacial till.
Study focus
Understanding the pathways facilitating groundwater flow and associated solute transport to the ocean is key for developing conceptual hydrogeologic models for coastal watersheds and for informing coastal zone management. Most local-scale field and modelling submarine groundwater discharge (SGD) studies have been conducted in high-permeability formations given the likely importance of SGD in these coastal settings. This study investigates direct (SGD) and indirect (seaward stream baseflow) groundwater discharge from a till dominated coastal aquifer using a combination of field measurements (river flow and baseflow separation, seepage meter measurements, and water temperature analysis) and a calibrated 3D numerical groundwater flow model.
New hydrological insights for the region
Results show that seaward stream baseflow greatly exceeds direct SGD to the ocean on the scale of the full harbour watershed (96.1% vs. 3.9 of total groundwater discharge). Particle tracking shows that the vast majority of SGD originates in the subcatchment immediately surrounding the harbour with limited intermediate or regional flow. The shorter flow paths and residence times for direct SGD results in less opportunity for natural attenuation processes and may have implications for groundwater-borne contamination to this harbour.
Mabou Harbour located in Cape Breton Island, Nova Scotia, Canada, is representative of the many natural harbours throughout the Maritime region of Canada as the surrounding landscape is overlain by glacial deposits, predominantly composed of glacial till.
Study focus
Understanding the pathways facilitating groundwater flow and associated solute transport to the ocean is key for developing conceptual hydrogeologic models for coastal watersheds and for informing coastal zone management. Most local-scale field and modelling submarine groundwater discharge (SGD) studies have been conducted in high-permeability formations given the likely importance of SGD in these coastal settings. This study investigates direct (SGD) and indirect (seaward stream baseflow) groundwater discharge from a till dominated coastal aquifer using a combination of field measurements (river flow and baseflow separation, seepage meter measurements, and water temperature analysis) and a calibrated 3D numerical groundwater flow model.
New hydrological insights for the region
Results show that seaward stream baseflow greatly exceeds direct SGD to the ocean on the scale of the full harbour watershed (96.1% vs. 3.9 of total groundwater discharge). Particle tracking shows that the vast majority of SGD originates in the subcatchment immediately surrounding the harbour with limited intermediate or regional flow. The shorter flow paths and residence times for direct SGD results in less opportunity for natural attenuation processes and may have implications for groundwater-borne contamination to this harbour.
Singh, Sarvesh; Banerjee, Bikram; Lato, Matthew; Sammut, Claude; Raval, Simit
Automated Rock Mass Discontinuity Set Characterisation Using Amplitude and Phase Decomposition of Point Cloud Data Journal Article
In: International Journal of Rock Mechanics and Mining Sciences, vol. 152, 2022.
@article{article1,
title = {Automated Rock Mass Discontinuity Set Characterisation Using Amplitude and Phase Decomposition of Point Cloud Data},
author = {Sarvesh Singh and Bikram Banerjee and Matthew Lato and Claude Sammut and Simit Raval},
doi = {10.1016/j.ijrmms.2022.105072},
year = {2022},
date = {2022-12-15},
urldate = {2022-12-19},
booktitle = {International Journal of Rock Mechanics and Mining Sciences},
journal = {International Journal of Rock Mechanics and Mining Sciences},
volume = {152},
abstract = {Laser scanning is an efficient approach for collecting rock mass point cloud scans to characterise structural discontinuities. However, developing computationally efficient and robust analytical workflows remains an open research problem. Existing semi-automated and automated approaches rely on point normals which are prone to mapping error when high variability exists in the local-support region. This study proposes a new automated algorithm that uses the spatial distribution of points on discontinuities to capture unique signatures in the form of sinusoidal waves. The discontinuities are then effectively characterised by clustering the amplitude and phase profiles of the sinusoidal waves. The presented amplitude and phase decomposition (APD) approach requires minimal pre-processing. Moreover, it can be applied directly to raw point clouds as filtering is inherently included through the fast Fourier transform (FFT) based decomposition of the signals. The method was evaluated on an underground tunnel dataset with exposed structural discontinuity planes. The efficacy of the developed approach was tested against manual segmentation using virtual compass plugin in open-source software (Cloud Compare), semi-automated open-source (discontinuity set extractor) and proprietary (Maptek PointStudio) software, and other automated algorithmic approaches based on point normal clustering and region growing. The APD approach produced the least error in estimating mean discontinuity dip angle and dip direction which was ±1.15° and ±1.39° with a dispersion error of ±2.24° and ±1.54°, respectively.},
keywords = {},
pubstate = {published},
tppubtype = {article}
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Laser scanning is an efficient approach for collecting rock mass point cloud scans to characterise structural discontinuities. However, developing computationally efficient and robust analytical workflows remains an open research problem. Existing semi-automated and automated approaches rely on point normals which are prone to mapping error when high variability exists in the local-support region. This study proposes a new automated algorithm that uses the spatial distribution of points on discontinuities to capture unique signatures in the form of sinusoidal waves. The discontinuities are then effectively characterised by clustering the amplitude and phase profiles of the sinusoidal waves. The presented amplitude and phase decomposition (APD) approach requires minimal pre-processing. Moreover, it can be applied directly to raw point clouds as filtering is inherently included through the fast Fourier transform (FFT) based decomposition of the signals. The method was evaluated on an underground tunnel dataset with exposed structural discontinuity planes. The efficacy of the developed approach was tested against manual segmentation using virtual compass plugin in open-source software (Cloud Compare), semi-automated open-source (discontinuity set extractor) and proprietary (Maptek PointStudio) software, and other automated algorithmic approaches based on point normal clustering and region growing. The APD approach produced the least error in estimating mean discontinuity dip angle and dip direction which was ±1.15° and ±1.39° with a dispersion error of ±2.24° and ±1.54°, respectively.
Camire, Felix; Strouth, Alex
Bow Valley Debris Flood Mitigation: Recent Progress and Lessons Learned Conference
Proceedings of the 8th Canadian Conference on Geotechnique and Natural Hazards: Innovative geoscience for tomorrow, 2022.
@conference{Conference1,
title = {Bow Valley Debris Flood Mitigation: Recent Progress and Lessons Learned },
author = {Felix Camire and Alex Strouth},
year = {2022},
date = {2022-12-06},
urldate = {2022-12-06},
booktitle = {Proceedings of the 8th Canadian Conference on Geotechnique and Natural Hazards: Innovative geoscience for tomorrow},
pages = {573-682},
abstract = {The 2013 floods in the Bow Valley, were devastating. In the Town of Canmore and the Municipal District of Bighorn, extreme rainfall led to debris floods and debris flows that damaged homes, businesses, and infrastructure. Flood protection works previously constructed suffered either extensive damage or complete loss. In response to the devastation, the two municipalities began a program of hazard and risk assessment, and options analysis and design. Some flood mitigation projects are currently under construction, while others are in different stages of design. This paper summarizes the storm and its associated damages, followed by descriptions of some projects that are being designed and under construction. Design details shared are focused on concepts that were not previously utilized in the Bow Valley. Furthermore, a section is dedicated to lessons learned from the construction of those projects, and the performance of constructed projects during high-flow events. Finally, the need for guidelines on debris flood and debris flow mitigation design is discussed.},
keywords = {},
pubstate = {published},
tppubtype = {conference}
}
The 2013 floods in the Bow Valley, were devastating. In the Town of Canmore and the Municipal District of Bighorn, extreme rainfall led to debris floods and debris flows that damaged homes, businesses, and infrastructure. Flood protection works previously constructed suffered either extensive damage or complete loss. In response to the devastation, the two municipalities began a program of hazard and risk assessment, and options analysis and design. Some flood mitigation projects are currently under construction, while others are in different stages of design. This paper summarizes the storm and its associated damages, followed by descriptions of some projects that are being designed and under construction. Design details shared are focused on concepts that were not previously utilized in the Bow Valley. Furthermore, a section is dedicated to lessons learned from the construction of those projects, and the performance of constructed projects during high-flow events. Finally, the need for guidelines on debris flood and debris flow mitigation design is discussed.
Pedraza, Oriol; Janeras, Marc; Gili, Josep; Luca, Struth; Buill, Felipe; Guinau, Marta; Ferre, Anna; Roca, Joan
Communicacion de la Geoinformacion 3D Mediante Visores Web y Entornos Inmersivos de Realidad Mixta en Problemas de Taludes y Laderas [Communication of 3D geoinformation through web viewers and mixed reality immersive environments in slope and slope problems] Conference
Simposio Nacional sobre Taludes y Laderas Inestables, 2022.
@conference{Conference1_105,
title = {Communicacion de la Geoinformacion 3D Mediante Visores Web y Entornos Inmersivos de Realidad Mixta en Problemas de Taludes y Laderas [Communication of 3D geoinformation through web viewers and mixed reality immersive environments in slope and slope problems]},
author = {Oriol Pedraza and Marc Janeras and Josep Gili and Struth Luca and Felipe Buill and Marta Guinau and Anna Ferre and Joan Roca},
year = {2022},
date = {2022-12-01},
booktitle = {Simposio Nacional sobre Taludes y Laderas Inestables},
abstract = {La revolución experimentada por el uso creciente de la geoinformación 3D en la ingeniería geológica, gracias a los avances tecnológicos, que progresivamente han facilitado una disponibilidad de técnicas de adquisición de datos y de herramientas para su análisis. Junto a los avances experimentados en la disponibilidad de recursos de computación y almacenamiento en la nube, han impulsado la expansión de numerosas aplicaciones que permiten la difusión de la geoinformación 3D en la web. A pesar de estos avances científico-técnicos, es común ver los datos 3D simplificados en imágenes estáticas 2D, perdiendo parte su potencialidad comunicativa. El objetivo de esta comunicación es presentar el diseño y las funcionalidades de unos visores web 3D de código abierto como una herramienta de sencilla utilización con la que interactuar y visualizar los resultados. Así mismo, estamos ensayando las posibilidades de la realidad mixta como una experiencia plenamente inmersiva para lograr una mejor comunicación de la geoinformación 3D.
The revolution experienced by the growing use of 3D geoinformation in engineering geological, thanks to technological advances, which have progressively facilitated the availability of data acquisition techniques and tools for analysis. Together the advances experienced in the availability of computing and storage resources in the cloud have promoted the expansion of numerous applications that allow the diffusion of 3D geoinformation on the web. Despite these scientific-technical advances, it is common to see data 3D simplified into 2D static images, losing part of its communicative potential. This communication aims to present the design and functionalities of some 3D web viewers open source as an easy-to-use tool to interact and visualize the results. Likewise, we are testing the possibilities of mixed reality as a fully immersive experience to better communicate 3D geoinformation.},
keywords = {},
pubstate = {published},
tppubtype = {conference}
}
La revolución experimentada por el uso creciente de la geoinformación 3D en la ingeniería geológica, gracias a los avances tecnológicos, que progresivamente han facilitado una disponibilidad de técnicas de adquisición de datos y de herramientas para su análisis. Junto a los avances experimentados en la disponibilidad de recursos de computación y almacenamiento en la nube, han impulsado la expansión de numerosas aplicaciones que permiten la difusión de la geoinformación 3D en la web. A pesar de estos avances científico-técnicos, es común ver los datos 3D simplificados en imágenes estáticas 2D, perdiendo parte su potencialidad comunicativa. El objetivo de esta comunicación es presentar el diseño y las funcionalidades de unos visores web 3D de código abierto como una herramienta de sencilla utilización con la que interactuar y visualizar los resultados. Así mismo, estamos ensayando las posibilidades de la realidad mixta como una experiencia plenamente inmersiva para lograr una mejor comunicación de la geoinformación 3D.
The revolution experienced by the growing use of 3D geoinformation in engineering geological, thanks to technological advances, which have progressively facilitated the availability of data acquisition techniques and tools for analysis. Together the advances experienced in the availability of computing and storage resources in the cloud have promoted the expansion of numerous applications that allow the diffusion of 3D geoinformation on the web. Despite these scientific-technical advances, it is common to see data 3D simplified into 2D static images, losing part of its communicative potential. This communication aims to present the design and functionalities of some 3D web viewers open source as an easy-to-use tool to interact and visualize the results. Likewise, we are testing the possibilities of mixed reality as a fully immersive experience to better communicate 3D geoinformation.
The revolution experienced by the growing use of 3D geoinformation in engineering geological, thanks to technological advances, which have progressively facilitated the availability of data acquisition techniques and tools for analysis. Together the advances experienced in the availability of computing and storage resources in the cloud have promoted the expansion of numerous applications that allow the diffusion of 3D geoinformation on the web. Despite these scientific-technical advances, it is common to see data 3D simplified into 2D static images, losing part of its communicative potential. This communication aims to present the design and functionalities of some 3D web viewers open source as an easy-to-use tool to interact and visualize the results. Likewise, we are testing the possibilities of mixed reality as a fully immersive experience to better communicate 3D geoinformation.
Abdulnabi, Ahlam; Beier, Nicholas; Smith, Lianna; Smith, Hilary; Macdonald, Gord
Comprehensive Geotechnical and Geochemical Characterisation of Two Diamond Ore Tailings Journal Article
In: Environmental Geotechnics, 2022.
@article{article1,
title = {Comprehensive Geotechnical and Geochemical Characterisation of Two Diamond Ore Tailings},
author = {Ahlam Abdulnabi and Nicholas Beier and Lianna Smith and Hilary Smith and Gord Macdonald},
doi = {10.1680/jenge.21.00012},
year = {2022},
date = {2022-11-18},
urldate = {2022-11-18},
journal = {Environmental Geotechnics},
abstract = {The physical and chemical stability of tailing deposits sometimes have conflicting priorities, yet they are rarely examined congruently comprehensively. This paper presents an investigation of the combined geotechnical and geochemical behaviours of two samples of diamond ore tailings. Detailed basic and advanced geotechnical laboratory characterisation tests were conducted to evaluate the particle size distribution, hindered sedimentation, compressibility, hydraulic conductivity and undrained shear strength of both tailings. Furthermore, duplicate specimens to evaluate the drainage effluent’s geochemical compositions were conducted to evaluate the compliance with regulatory concentration criteria. The cation and anion concentrations of the expelled water were analysed at different consolidation stages, along with other basic geochemical index properties such as pH, redox potential and electrical conductivity. Both the geotechnical large strain consolidation testing and geochemical pore fluid collection were performed in a controlled-temperature environment to represent the cold climatic regime at the mine site. Tests were performed in a walk-in freezer with a nominal ambient temperature of 4–5°C. Moreover, the drainage effluent from the large-strain consolidation geochemical duplicates was collected using an innovative sampling system that ensured that the sample was not exposed to the atmosphere. The geotechnical and geochemical implications of both tailing treatments are discussed.},
keywords = {},
pubstate = {published},
tppubtype = {article}
}
The physical and chemical stability of tailing deposits sometimes have conflicting priorities, yet they are rarely examined congruently comprehensively. This paper presents an investigation of the combined geotechnical and geochemical behaviours of two samples of diamond ore tailings. Detailed basic and advanced geotechnical laboratory characterisation tests were conducted to evaluate the particle size distribution, hindered sedimentation, compressibility, hydraulic conductivity and undrained shear strength of both tailings. Furthermore, duplicate specimens to evaluate the drainage effluent’s geochemical compositions were conducted to evaluate the compliance with regulatory concentration criteria. The cation and anion concentrations of the expelled water were analysed at different consolidation stages, along with other basic geochemical index properties such as pH, redox potential and electrical conductivity. Both the geotechnical large strain consolidation testing and geochemical pore fluid collection were performed in a controlled-temperature environment to represent the cold climatic regime at the mine site. Tests were performed in a walk-in freezer with a nominal ambient temperature of 4–5°C. Moreover, the drainage effluent from the large-strain consolidation geochemical duplicates was collected using an innovative sampling system that ensured that the sample was not exposed to the atmosphere. The geotechnical and geochemical implications of both tailing treatments are discussed.
Porter, Mike; Quinn, Pete; Barlow, Pete
Conceptual Landslide Velocity Transition Models for a Range of Landslide Behaviour Types Conference
Proceedings of the 8th Canadian Conference on Geotechnique and Natural Hazards: Innovative geoscience for tomorrow, 2022.
@conference{Conference1,
title = {Conceptual Landslide Velocity Transition Models for a Range of Landslide Behaviour Types },
author = {Mike Porter and Pete Quinn and Pete Barlow},
year = {2022},
date = {2022-11-17},
urldate = {2022-11-17},
booktitle = {Proceedings of the 8th Canadian Conference on Geotechnique and Natural Hazards: Innovative geoscience for tomorrow},
abstract = {The potential variability in velocity of normally slow-moving landslides has important implications for risk assessment, design, monitoring, and maintenance of infrastructure. A conceptual approach to predict landslide velocity probability distributions using landslide observations, engineering judgment and Markov models is reviewed. Landslide behaviour types that link historical evidence of landslide displacement and mechanisms of movement to probabilistic predictions of future velocity are proposed. Tentative velocity transition matrices are proposed for five landslide behaviour types which yield limiting state probability vectors corresponding to long-term average annual landslide displacements ranging from 1 cm/yr to 1 m/yr. Typical model outputs are provided and potential model applications are discussed.},
keywords = {},
pubstate = {published},
tppubtype = {conference}
}
The potential variability in velocity of normally slow-moving landslides has important implications for risk assessment, design, monitoring, and maintenance of infrastructure. A conceptual approach to predict landslide velocity probability distributions using landslide observations, engineering judgment and Markov models is reviewed. Landslide behaviour types that link historical evidence of landslide displacement and mechanisms of movement to probabilistic predictions of future velocity are proposed. Tentative velocity transition matrices are proposed for five landslide behaviour types which yield limiting state probability vectors corresponding to long-term average annual landslide displacements ranging from 1 cm/yr to 1 m/yr. Typical model outputs are provided and potential model applications are discussed.
Massey, Chris; Wolter, Andrea; Huso, Rand; Lukovic, Biljana; Brideau, Marc-Andre
Coseismic Landslide Susceptibility and Triggering Analyses Book Chapter
In: Coseismic landslides: Phenomena, long-term effects and mitigation, pp. 633-679, 2022.
@inbook{Bookchp1j,
title = {Coseismic Landslide Susceptibility and Triggering Analyses},
author = {Chris Massey and Andrea Wolter and Rand Huso and Biljana Lukovic and Marc-Andre Brideau},
url = {https://link.springer.com/book/10.1007/978-981-19-6597-5},
year = {2022},
date = {2022-11-16},
booktitle = {Coseismic landslides: Phenomena, long-term effects and mitigation},
pages = {633-679},
abstract = {This chapter reviews the methods used to carry out coseismic landslide susceptibility and slope stability analyses, from the regional- to the site-scale and based on user needs, data requirements and constraints. Earthquake-induced landslide (EIL) triggering metrics (ground shaking) are discussed and linked to landslide severity and other environmental impacts likely to occur at different levels of ground shaking. Six case studies are used to explore the various methods of determining coseismic landslide susceptibility and slope stability analyses, the metrics they produce, the scale of applicability and data requirements. The key developments and challenges of each method are discussed and summarised. One such challenge is that the efficacy of each method is limited by the availability of the input data and/or the ability to derive it, irrespective of the project scale or need. Possibly the largest challenge for experts is the ability to transfer the results from such models into actionable information (e.g. hazard and risk analyses and engineering design) to support science-based decision-making.},
keywords = {},
pubstate = {published},
tppubtype = {inbook}
}
This chapter reviews the methods used to carry out coseismic landslide susceptibility and slope stability analyses, from the regional- to the site-scale and based on user needs, data requirements and constraints. Earthquake-induced landslide (EIL) triggering metrics (ground shaking) are discussed and linked to landslide severity and other environmental impacts likely to occur at different levels of ground shaking. Six case studies are used to explore the various methods of determining coseismic landslide susceptibility and slope stability analyses, the metrics they produce, the scale of applicability and data requirements. The key developments and challenges of each method are discussed and summarised. One such challenge is that the efficacy of each method is limited by the availability of the input data and/or the ability to derive it, irrespective of the project scale or need. Possibly the largest challenge for experts is the ability to transfer the results from such models into actionable information (e.g. hazard and risk analyses and engineering design) to support science-based decision-making.
Jakob, Matthias; Davidson, Sarah; Bullard, Gemma; Busslinger, Matthias; Collier-Pandya, Beatrice; Grover, Patrick; Lau, Carie-Ann
Debris-Flood Hazard Assessments in Steep Streams Journal Article
In: Water Resources Research, vol. 58, no. 4, 2022.
@article{article1,
title = {Debris-Flood Hazard Assessments in Steep Streams},
author = {Matthias Jakob and Sarah Davidson and Gemma Bullard and Matthias Busslinger and Beatrice Collier-Pandya and Patrick Grover and Carie-Ann Lau},
doi = {10.1029/2021WR030907},
year = {2022},
date = {2022-11-15},
urldate = {2022-11-15},
journal = {Water Resources Research},
volume = {58},
number = {4},
abstract = {Debris floods most commonly occur in steep mountain channels and on their alluvial fans
but can also occur on small gravel bed rivers with watershed areas up to several hundred square kilometers.
This became obvious during July 2021 and November 2021 debris floods in northwestern Germany and
southwestern British Columbia, Canada. We subdivide debris floods into three categories: those triggered by
a supra-critical bed shear stress ratio, form by dilution from debris flows, and resulting from outbreak floods.
This trichotomy challenges traditional hazard assessments; debris floods classify as a fluvial process, yet their
destructive mechanics are difficult to characterize. Key hazards interact spatially and temporally in debris
floods: inundation, scour, sediment transport and deposition and bank erosion. We describe approaches to
quantify hazards by systematically accounting for these processes and introduce a novel approach for hazard
quantification and mapping in which flow velocity, depth, and presumed fluid density are combined with
the annual event frequency for all event scenarios. The derivative “composite hazard maps” are equally valid
for debris floods and debris flows. Isolines of bank erosion based on a probabilistic analysis of a physically
based model are added to capture the potential of debris floods to abruptly widen their channels. Substantial
challenges remain, specifically in the reliable prediction of sediment transport and progressive bank erosion.
Our intention is to homogenize debris-flood hazard assessments and especially mapping methodologies. This
could allow for systematic integration with landuse policies assuring consistency among approaches executed
by practitioners acting in this field.},
keywords = {},
pubstate = {published},
tppubtype = {article}
}
Debris floods most commonly occur in steep mountain channels and on their alluvial fans
but can also occur on small gravel bed rivers with watershed areas up to several hundred square kilometers.
This became obvious during July 2021 and November 2021 debris floods in northwestern Germany and
southwestern British Columbia, Canada. We subdivide debris floods into three categories: those triggered by
a supra-critical bed shear stress ratio, form by dilution from debris flows, and resulting from outbreak floods.
This trichotomy challenges traditional hazard assessments; debris floods classify as a fluvial process, yet their
destructive mechanics are difficult to characterize. Key hazards interact spatially and temporally in debris
floods: inundation, scour, sediment transport and deposition and bank erosion. We describe approaches to
quantify hazards by systematically accounting for these processes and introduce a novel approach for hazard
quantification and mapping in which flow velocity, depth, and presumed fluid density are combined with
the annual event frequency for all event scenarios. The derivative “composite hazard maps” are equally valid
for debris floods and debris flows. Isolines of bank erosion based on a probabilistic analysis of a physically
based model are added to capture the potential of debris floods to abruptly widen their channels. Substantial
challenges remain, specifically in the reliable prediction of sediment transport and progressive bank erosion.
Our intention is to homogenize debris-flood hazard assessments and especially mapping methodologies. This
could allow for systematic integration with landuse policies assuring consistency among approaches executed
by practitioners acting in this field.
but can also occur on small gravel bed rivers with watershed areas up to several hundred square kilometers.
This became obvious during July 2021 and November 2021 debris floods in northwestern Germany and
southwestern British Columbia, Canada. We subdivide debris floods into three categories: those triggered by
a supra-critical bed shear stress ratio, form by dilution from debris flows, and resulting from outbreak floods.
This trichotomy challenges traditional hazard assessments; debris floods classify as a fluvial process, yet their
destructive mechanics are difficult to characterize. Key hazards interact spatially and temporally in debris
floods: inundation, scour, sediment transport and deposition and bank erosion. We describe approaches to
quantify hazards by systematically accounting for these processes and introduce a novel approach for hazard
quantification and mapping in which flow velocity, depth, and presumed fluid density are combined with
the annual event frequency for all event scenarios. The derivative “composite hazard maps” are equally valid
for debris floods and debris flows. Isolines of bank erosion based on a probabilistic analysis of a physically
based model are added to capture the potential of debris floods to abruptly widen their channels. Substantial
challenges remain, specifically in the reliable prediction of sediment transport and progressive bank erosion.
Our intention is to homogenize debris-flood hazard assessments and especially mapping methodologies. This
could allow for systematic integration with landuse policies assuring consistency among approaches executed
by practitioners acting in this field.
Mitchell, Andrew; Zubrycky, Sophia; McDougall, Scott; Aaron, Jordan; Graf, Christoph; Jacquemart, Mylene; Hubl, Johannes; Kaitna, Roland
Debris Flow Surges in a Numerical Model - Mount Currie Case Study Conference
Proceedings of the 8th Canadian Conference on Geotechnique and Natural Hazards: Innovative geoscience for tomorrow, 2022.
@conference{Conference1,
title = {Debris Flow Surges in a Numerical Model - Mount Currie Case Study},
author = {Andrew Mitchell and Sophia Zubrycky and Scott McDougall and Jordan Aaron and Christoph Graf and Mylene Jacquemart and Johannes Hubl and Roland Kaitna},
year = {2022},
date = {2022-11-14},
urldate = {2022-11-14},
booktitle = {Proceedings of the 8th Canadian Conference on Geotechnique and Natural Hazards: Innovative geoscience for tomorrow},
pages = {179-185},
abstract = {The mobility of debris flows is highly variable, which makes runout prediction challenging. Numerical runout models are often used to estimate inundation area, flow depth and velocity for debris-flow analyses. Runout models typically use initiation conditions that disregard the fact that debris flows commonly occur in multiple surges. In this work, we modified the Dan3D runout model to enable a more realistic hydrograph initiation condition. We analyzed a 2019 debris flow at Mount Currie in southwestern British Columbia to examine the effects of complex inflow hydrographs on model outputs. The impact area, flow depths and velocities were sensitive to the inflow hydrograph, particularly depths and velocities higher on the fan. The results from the case study demonstrated that, in addition to variations in material and rheological parameters, the simulated debris flow runout is sensitive to variations in the inflow hydrograph. The numerical model results are also interpreted using an empirical runout relationship to assess the plausibility of the numerical results.},
keywords = {},
pubstate = {published},
tppubtype = {conference}
}
The mobility of debris flows is highly variable, which makes runout prediction challenging. Numerical runout models are often used to estimate inundation area, flow depth and velocity for debris-flow analyses. Runout models typically use initiation conditions that disregard the fact that debris flows commonly occur in multiple surges. In this work, we modified the Dan3D runout model to enable a more realistic hydrograph initiation condition. We analyzed a 2019 debris flow at Mount Currie in southwestern British Columbia to examine the effects of complex inflow hydrographs on model outputs. The impact area, flow depths and velocities were sensitive to the inflow hydrograph, particularly depths and velocities higher on the fan. The results from the case study demonstrated that, in addition to variations in material and rheological parameters, the simulated debris flow runout is sensitive to variations in the inflow hydrograph. The numerical model results are also interpreted using an empirical runout relationship to assess the plausibility of the numerical results.
Piton, Guillaume; Goodwin, Saoirse; Mark, Emily; Strouth, Alex
Debris Flows, Boulders and Constrictions: A Simple Framework for Modeling Jamming, and Its Consequences on Outflow Journal Article
In: Journal of Geophysical Research: Earth Surface, vol. 127, no. 5, 2022.
@article{article1,
title = {Debris Flows, Boulders and Constrictions: A Simple Framework for Modeling Jamming, and Its Consequences on Outflow},
author = {Guillaume Piton and Saoirse Goodwin and Emily Mark and Alex Strouth},
doi = {10.1029/2021JF006447},
year = {2022},
date = {2022-11-12},
urldate = {2022-11-12},
journal = {Journal of Geophysical Research: Earth Surface},
volume = {127},
number = {5},
abstract = {Large boulders can jam in constrictions, both in canyons and man-made structures (e.g., slit-dams). Boulder jamming occurs stochastically, and partially governs the outflow rate of debris flow material. Explicit hydro-mechanical models of boulder-laden flows are too computationally demanding to study this stochasticity. This study presents a new framework implemented into a numerical program. This program encapsulates basic hydraulic equations and criteria predicting boulder blockage at narrow sections, along with a simple statistical way to compute boulder sizes and numbers. The program applies empirical estimates by experts of the average number of boulders in a deposit to evaluate how equivalent multi-phase flows would interact with a constriction. The model stochastically generates boulders that can obstruct the constriction(s). The program outputs simple descriptions of the upstream flow level over time, as well as the downstream outlet discharge rate and volume. The model is fast (5–30 s per run), allowing uncertainty propagation analyses of interactions between flows, boulders and constrictions. Interaction between both low- and high-risk flows can be quickly evaluated for different scenarios. For uncertainty propagation, we use possibility theory, which accommodates uncertainties relevant to debris flows. The framework gives practitioners a much-needed generalized approach for understanding the long-term behavior of boulder-laden flows through canyons, or for designing engineered structures. Finally, we apply the model to a field case – the design of a proposed North American slit-dam – thence elucidating the design requirements for effective flow control. We found that horizontal bars are necessary for dependably controlling outflow from this structure.},
keywords = {},
pubstate = {published},
tppubtype = {article}
}
Large boulders can jam in constrictions, both in canyons and man-made structures (e.g., slit-dams). Boulder jamming occurs stochastically, and partially governs the outflow rate of debris flow material. Explicit hydro-mechanical models of boulder-laden flows are too computationally demanding to study this stochasticity. This study presents a new framework implemented into a numerical program. This program encapsulates basic hydraulic equations and criteria predicting boulder blockage at narrow sections, along with a simple statistical way to compute boulder sizes and numbers. The program applies empirical estimates by experts of the average number of boulders in a deposit to evaluate how equivalent multi-phase flows would interact with a constriction. The model stochastically generates boulders that can obstruct the constriction(s). The program outputs simple descriptions of the upstream flow level over time, as well as the downstream outlet discharge rate and volume. The model is fast (5–30 s per run), allowing uncertainty propagation analyses of interactions between flows, boulders and constrictions. Interaction between both low- and high-risk flows can be quickly evaluated for different scenarios. For uncertainty propagation, we use possibility theory, which accommodates uncertainties relevant to debris flows. The framework gives practitioners a much-needed generalized approach for understanding the long-term behavior of boulder-laden flows through canyons, or for designing engineered structures. Finally, we apply the model to a field case – the design of a proposed North American slit-dam – thence elucidating the design requirements for effective flow control. We found that horizontal bars are necessary for dependably controlling outflow from this structure.
Kostaschuk, Rod; Gaib, Sarah; Gygax, Adrian
Design and Construction of Stabilization Measures for Highway 99, Ten Mile Slide, Lillooet, BC Conference
GeoCalgary, 2022.
@conference{Conference1,
title = {Design and Construction of Stabilization Measures for Highway 99, Ten Mile Slide, Lillooet, BC},
author = {Rod Kostaschuk and Sarah Gaib and Adrian Gygax},
year = {2022},
date = {2022-11-11},
urldate = {2022-11-11},
booktitle = {GeoCalgary},
abstract = {Slope stabilization at the Ten Mile Slide undertaken by the BC Ministry of Transportation and Infrastructure (Ministry) on Highway 99 was successfully completed in Fall 2021, resulting in improved long-term safety and reliability for people and goods travelling the highway and the CN rail line above, supporting the local forestry, mining and agricultural resource sectors. Highway 99 is an essential route between the rural communities of Lillooet, Xaxli’p first nation and transportation networks in Kamloops. The landslide has been active for decades and now spans the highway approximately 17 km northeast of Lillooet on the south side of the Fraser River. Ten Mile Slide is 200 m wide at the highway and 300 m long with an estimated volume of 1,000,000 m3 of soil material and forms part of a much larger, dormant “soil glacier” called the Tunnel Earthflow. The slide is a geotechnical anomaly being one of the only known continuously moving landslides in North America. Prior to stabilization, average movement rates were typically 10 mm/day with rates up to 50 mm/day following precipitation events.},
keywords = {},
pubstate = {published},
tppubtype = {conference}
}
Slope stabilization at the Ten Mile Slide undertaken by the BC Ministry of Transportation and Infrastructure (Ministry) on Highway 99 was successfully completed in Fall 2021, resulting in improved long-term safety and reliability for people and goods travelling the highway and the CN rail line above, supporting the local forestry, mining and agricultural resource sectors. Highway 99 is an essential route between the rural communities of Lillooet, Xaxli’p first nation and transportation networks in Kamloops. The landslide has been active for decades and now spans the highway approximately 17 km northeast of Lillooet on the south side of the Fraser River. Ten Mile Slide is 200 m wide at the highway and 300 m long with an estimated volume of 1,000,000 m3 of soil material and forms part of a much larger, dormant “soil glacier” called the Tunnel Earthflow. The slide is a geotechnical anomaly being one of the only known continuously moving landslides in North America. Prior to stabilization, average movement rates were typically 10 mm/day with rates up to 50 mm/day following precipitation events.
Zulkoski, Caroline
Design Parameters for Using Controlled Low-Strength Material Backfill to Manage Axial Soil Loads on Buried Pipelines Masters Thesis
2022.
@mastersthesis{masters1,
title = {Design Parameters for Using Controlled Low-Strength Material Backfill to Manage Axial Soil Loads on Buried Pipelines},
author = {Caroline Zulkoski},
doi = {10.14288/1.0421281},
year = {2022},
date = {2022-11-09},
urldate = {2022-11-09},
abstract = {Buried pipeline systems form a key component of the oil and gas transportation infrastructure, and the performance of these systems located in areas subject to potential ground movements is a critical consideration in engineering design. In mitigating against future or on-going ground displacement hazards, there are instances where the axial soil restraint (soil anchoring capacity) needs to be increased to avoid transferring loads to adjacent potentially vulnerable components in the pipeline system. One method to increase axial soil restraint is to increase the effective diameter of the pipeline. This can be done by encasing the pipeline in controlled, low-strength material (CLSM). The use of CLSM to increase axial soil restraint on buried pipelines requires that the axial load to produce pipe-CLSM interface bond failure be greater than that required for failure at the CLSM-soil interface. To advance the state of knowledge of the axial failure mechanisms of the soil-CLSM-pipe composite, a systematic full-scale testing program was undertaken using the Advanced Soil Pipe Interaction Research (ASPIReTM) modeling chamber at the University of British Columbia. First, twenty-two pipe-CLSM axial pullout tests were completed to assess the bond strength at the interface between CLSM and NPS 8 steel pipe specimens with various coatings. The research findings are presented, and the bond strength is assessed as a percentage of compressional strength to compare to observations from other researchers. Next, five full-scale axial pullout tests on pipes encased in CLSM, and in turn, buried in a soil backfill were conducted, using the results from the pipe-CLSM bond strength testing as well as two initial calibration tests. The work involved special modifications to the existing testing system. The test results are compared to those predicted using the PRCI (2009) guidelines. The ultimate loads measured are in good agreement with the predictions confirming the suitability of current guidelines employed to estimate the anchoring forces generated by encasing pipelines in CLSM backfill.
},
keywords = {},
pubstate = {published},
tppubtype = {mastersthesis}
}
Buried pipeline systems form a key component of the oil and gas transportation infrastructure, and the performance of these systems located in areas subject to potential ground movements is a critical consideration in engineering design. In mitigating against future or on-going ground displacement hazards, there are instances where the axial soil restraint (soil anchoring capacity) needs to be increased to avoid transferring loads to adjacent potentially vulnerable components in the pipeline system. One method to increase axial soil restraint is to increase the effective diameter of the pipeline. This can be done by encasing the pipeline in controlled, low-strength material (CLSM). The use of CLSM to increase axial soil restraint on buried pipelines requires that the axial load to produce pipe-CLSM interface bond failure be greater than that required for failure at the CLSM-soil interface. To advance the state of knowledge of the axial failure mechanisms of the soil-CLSM-pipe composite, a systematic full-scale testing program was undertaken using the Advanced Soil Pipe Interaction Research (ASPIReTM) modeling chamber at the University of British Columbia. First, twenty-two pipe-CLSM axial pullout tests were completed to assess the bond strength at the interface between CLSM and NPS 8 steel pipe specimens with various coatings. The research findings are presented, and the bond strength is assessed as a percentage of compressional strength to compare to observations from other researchers. Next, five full-scale axial pullout tests on pipes encased in CLSM, and in turn, buried in a soil backfill were conducted, using the results from the pipe-CLSM bond strength testing as well as two initial calibration tests. The work involved special modifications to the existing testing system. The test results are compared to those predicted using the PRCI (2009) guidelines. The ultimate loads measured are in good agreement with the predictions confirming the suitability of current guidelines employed to estimate the anchoring forces generated by encasing pipelines in CLSM backfill.
Froese, Corey; Engelbrecht, Jeanine; Gousseau, Zachary; Diederichs, Kaitlyn; Zahradka, Aron
Development of Landslide Early Warning Thresholds for Normally Slow-Moving Landslide in the Western Canada Sedimentary Basin Conference
Proceedings of the 8th Canadian Conference on Geotechnique and Natural Hazards: Innovative geoscience for tomorrow, 2022.
@conference{Conference1,
title = {Development of Landslide Early Warning Thresholds for Normally Slow-Moving Landslide in the Western Canada Sedimentary Basin},
author = {Corey Froese and Jeanine Engelbrecht and Zachary Gousseau and Kaitlyn Diederichs and Aron Zahradka},
year = {2022},
date = {2022-11-01},
urldate = {2022-11-01},
booktitle = {Proceedings of the 8th Canadian Conference on Geotechnique and Natural Hazards: Innovative geoscience for tomorrow},
journal = {Canadian Geohazards Conference },
pages = {503-510},
abstract = {In 2021, a project in the Western Canada Sedimentary Basin brought together five pipeline operators to support building a regional understanding of the relationships between landslide velocity and variations in hydroclimatic parameters, such as snow melt, precipitation, and soil moisture. Over 300 slope inclinometers, 40 Shape Accel Arrays, and regional InSAR displacement data were utilized to build time-displacement plots for over 40 individual slopes to review velocity trends ranging back nearly 30 years. These data were then compared with satellite-derived climate models to support the assessment of the effect of different hydroclimatic parameters on historical landslide accelerations. The initial data review highlighted spatial and temporal variations in the relative importance of hydroclimatic conditions, especially soil moisture and precipitation, in driving landslide activity accelerations. These observations will support regional situational awareness and ultimately the development of data driven exceedance alerts for landslide early warning.},
keywords = {},
pubstate = {published},
tppubtype = {conference}
}
In 2021, a project in the Western Canada Sedimentary Basin brought together five pipeline operators to support building a regional understanding of the relationships between landslide velocity and variations in hydroclimatic parameters, such as snow melt, precipitation, and soil moisture. Over 300 slope inclinometers, 40 Shape Accel Arrays, and regional InSAR displacement data were utilized to build time-displacement plots for over 40 individual slopes to review velocity trends ranging back nearly 30 years. These data were then compared with satellite-derived climate models to support the assessment of the effect of different hydroclimatic parameters on historical landslide accelerations. The initial data review highlighted spatial and temporal variations in the relative importance of hydroclimatic conditions, especially soil moisture and precipitation, in driving landslide activity accelerations. These observations will support regional situational awareness and ultimately the development of data driven exceedance alerts for landslide early warning.
Brown, Tanaya; Priscu, Caius; Küpper, Angela
Deviance Accountability Reports: Considerations for a Practical Approach Conference
Tailings and Mine Waste '22, 2022.
@conference{Conference1,
title = {Deviance Accountability Reports: Considerations for a Practical Approach },
author = {Tanaya Brown and Caius Priscu and Angela Küpper},
year = {2022},
date = {2022-10-28},
urldate = {2022-10-28},
booktitle = {Tailings and Mine Waste '22},
abstract = {The GISTM (GTR, 2020) includes topics, principles, and requirements aimed to “achieve the ultimate goal of zero harm to people and the environment with zero tolerance for human fatality” and “provide a framework for safe tailings facility management while affording tailings dam owners flexibility as to how best to achieve this goal”. As part of Principle 6 “Plan, build and operate the tailings facility to manage risk at all phases of the tailings facility lifecycle, including closure and post-closure”, the concept of a Deviance Accountability Report (DAR) is introduced as a method to assess the impact of cumulative changes on the risk level of as-built tailings facilities. The DAR is a key component of the risk management system. The paper proposes a DAR workflow that allows for facility-specific understanding to be incorporated, while still allowing for a structured approach that will enable the DAR to serve as intended to assess the cumulative impact of changes that may have been individually approved, on the risk level of a tailings facility, integrate understanding of a tailings facility risks throughout its lifecycle, pro-vide basis to make risk-informed decisions, and provide a mechanism to approve and implement risk management recommendations.},
keywords = {},
pubstate = {published},
tppubtype = {conference}
}
The GISTM (GTR, 2020) includes topics, principles, and requirements aimed to “achieve the ultimate goal of zero harm to people and the environment with zero tolerance for human fatality” and “provide a framework for safe tailings facility management while affording tailings dam owners flexibility as to how best to achieve this goal”. As part of Principle 6 “Plan, build and operate the tailings facility to manage risk at all phases of the tailings facility lifecycle, including closure and post-closure”, the concept of a Deviance Accountability Report (DAR) is introduced as a method to assess the impact of cumulative changes on the risk level of as-built tailings facilities. The DAR is a key component of the risk management system. The paper proposes a DAR workflow that allows for facility-specific understanding to be incorporated, while still allowing for a structured approach that will enable the DAR to serve as intended to assess the cumulative impact of changes that may have been individually approved, on the risk level of a tailings facility, integrate understanding of a tailings facility risks throughout its lifecycle, pro-vide basis to make risk-informed decisions, and provide a mechanism to approve and implement risk management recommendations.
Koenig, Cassandra; Hauck, Christian; Arenson, Lukas; Hilbich, Christin
EGU General Assembly, 2022.
@conference{Conference1,
title = {Effects of Geologic Heterogeneity on Permafrost Distribution and Catchment Hydrology in Mountain Environments},
author = {Cassandra Koenig and Christian Hauck and Lukas Arenson and Christin Hilbich},
doi = {10.5194/egusphere-egu22-12146},
year = {2022},
date = {2022-10-27},
urldate = {2022-10-27},
booktitle = {EGU General Assembly},
abstract = {Changes in surface runoff from permafrost thaw in mountain catchments can be estimated using numerical cryo-hydrogeology models. However, such models can be complex from a numerical standpoint due to the need to simulate transient thermo-hydrologic feedbacks in highly heterogenous geological settings. Models that also seek to quantify water movement and water-budget contributions from ground-ice thaw must further account for changes in water/ice saturation to continually estimate and update the physical properties that control heat and water transfer in the ground (i.e., thermal and hydraulic conductivity) during the model execution. This has important implications for permafrost hydrology modelling efforts in arid mountain watersheds like the High Andes, where water security is threatened by climate change and the role of permafrost in the hydrologic cycle is unclear.
In this contribution the coupled finite element codes TEMP/W and SEEP/W are used to illustrate ground thermal and hydrologic dynamics for different geological scenarios within a hypothetical mountain slope, characteristic of the High Andes at an altitude of up to 6000 m. The 3 km-long, two dimensional cross-sectional model was developed based on a simplified topography, and ground temperatures and climate data collected within the region. In the first scenario, a uniform hydraulic conductivity is applied to the full model domain. A second scenario simulates a case where the hydraulic conductivity of the ground in the upper 200 m is an order of magnitude higher than for the rest of the model (i.e., as in fractured bedrock or unconsolidated sediment). The scenarios were subjected to a 1,000-yr seasonally cyclic climate forcing, followed by 1,000 years of warming superimposed on inter-annual variability at an average warming rate of 4 deg/100 year.
Model experiments show that the applied variations in hydraulic conductivity support vastly different permafrost and ground ice-content distributions under identical climate forcing. Compared to the uniform hydraulic conductivity case, the scenario with high hydraulic conductivity upper layer produces an increase in the heterogeneity of ice-rich permafrost under the stable climate forcing, and a slightly accelerated rate of permafrost thaw under climate warming. Higher recharge and discharge fluxes across the model surface are also predicted for the high hydraulic conductivity scenario.
The divergence in the results is attributed to preferential flow paths that develop near the model surface in the higher hydraulic conductivity case, which in turn leads to increased spatial complexity in advective heat transfer. This can have profound effects on predictive models aiming to estimate rates of permafrost thaw and discharge behaviour under climate warming, and highlights the need for awareness of uncertainties associated with estimated or assumed thermal and hydrologic properties in modelling large mountain catchments.},
keywords = {},
pubstate = {published},
tppubtype = {conference}
}
Changes in surface runoff from permafrost thaw in mountain catchments can be estimated using numerical cryo-hydrogeology models. However, such models can be complex from a numerical standpoint due to the need to simulate transient thermo-hydrologic feedbacks in highly heterogenous geological settings. Models that also seek to quantify water movement and water-budget contributions from ground-ice thaw must further account for changes in water/ice saturation to continually estimate and update the physical properties that control heat and water transfer in the ground (i.e., thermal and hydraulic conductivity) during the model execution. This has important implications for permafrost hydrology modelling efforts in arid mountain watersheds like the High Andes, where water security is threatened by climate change and the role of permafrost in the hydrologic cycle is unclear.
In this contribution the coupled finite element codes TEMP/W and SEEP/W are used to illustrate ground thermal and hydrologic dynamics for different geological scenarios within a hypothetical mountain slope, characteristic of the High Andes at an altitude of up to 6000 m. The 3 km-long, two dimensional cross-sectional model was developed based on a simplified topography, and ground temperatures and climate data collected within the region. In the first scenario, a uniform hydraulic conductivity is applied to the full model domain. A second scenario simulates a case where the hydraulic conductivity of the ground in the upper 200 m is an order of magnitude higher than for the rest of the model (i.e., as in fractured bedrock or unconsolidated sediment). The scenarios were subjected to a 1,000-yr seasonally cyclic climate forcing, followed by 1,000 years of warming superimposed on inter-annual variability at an average warming rate of 4 deg/100 year.
Model experiments show that the applied variations in hydraulic conductivity support vastly different permafrost and ground ice-content distributions under identical climate forcing. Compared to the uniform hydraulic conductivity case, the scenario with high hydraulic conductivity upper layer produces an increase in the heterogeneity of ice-rich permafrost under the stable climate forcing, and a slightly accelerated rate of permafrost thaw under climate warming. Higher recharge and discharge fluxes across the model surface are also predicted for the high hydraulic conductivity scenario.
The divergence in the results is attributed to preferential flow paths that develop near the model surface in the higher hydraulic conductivity case, which in turn leads to increased spatial complexity in advective heat transfer. This can have profound effects on predictive models aiming to estimate rates of permafrost thaw and discharge behaviour under climate warming, and highlights the need for awareness of uncertainties associated with estimated or assumed thermal and hydrologic properties in modelling large mountain catchments.
In this contribution the coupled finite element codes TEMP/W and SEEP/W are used to illustrate ground thermal and hydrologic dynamics for different geological scenarios within a hypothetical mountain slope, characteristic of the High Andes at an altitude of up to 6000 m. The 3 km-long, two dimensional cross-sectional model was developed based on a simplified topography, and ground temperatures and climate data collected within the region. In the first scenario, a uniform hydraulic conductivity is applied to the full model domain. A second scenario simulates a case where the hydraulic conductivity of the ground in the upper 200 m is an order of magnitude higher than for the rest of the model (i.e., as in fractured bedrock or unconsolidated sediment). The scenarios were subjected to a 1,000-yr seasonally cyclic climate forcing, followed by 1,000 years of warming superimposed on inter-annual variability at an average warming rate of 4 deg/100 year.
Model experiments show that the applied variations in hydraulic conductivity support vastly different permafrost and ground ice-content distributions under identical climate forcing. Compared to the uniform hydraulic conductivity case, the scenario with high hydraulic conductivity upper layer produces an increase in the heterogeneity of ice-rich permafrost under the stable climate forcing, and a slightly accelerated rate of permafrost thaw under climate warming. Higher recharge and discharge fluxes across the model surface are also predicted for the high hydraulic conductivity scenario.
The divergence in the results is attributed to preferential flow paths that develop near the model surface in the higher hydraulic conductivity case, which in turn leads to increased spatial complexity in advective heat transfer. This can have profound effects on predictive models aiming to estimate rates of permafrost thaw and discharge behaviour under climate warming, and highlights the need for awareness of uncertainties associated with estimated or assumed thermal and hydrologic properties in modelling large mountain catchments.
Roesky, Benjamin; Hayashi, Masaki
Effects of Lake-Groundwater Interaction on the Thermal Regime of a Sub-Alpine Headwater Stream Journal Article
In: Hydrological Processes, vol. 36, no. 2, 2022.
@article{article1,
title = {Effects of Lake-Groundwater Interaction on the Thermal Regime of a Sub-Alpine Headwater Stream},
author = {Benjamin Roesky and Masaki Hayashi},
doi = {10.1002/hyp.14501},
year = {2022},
date = {2022-10-26},
urldate = {2022-10-28},
journal = {Hydrological Processes},
volume = {36},
number = {2},
abstract = {Stream thermal regimes are critical to the stability of freshwater habitats. There is growing concern that climate change will result in stream warming due to rising air temperatures, decreased shading in forested areas due to wildfires, and changes in streamflow. Groundwater plays an important role in controlling stream temperatures in mountain headwaters, where it makes up a considerable portion of discharge. This study investigated the controls on the thermal regime of a headwater stream, and the surrounding groundwater processes, in a catchment on the eastern slopes of the Canadian Rocky Mountains. Groundwater discharge to the headwater spring is partially sourced by a seasonal lake. Spring, stream, and lake temperature, water level, discharge and chemistry data were used to build a conceptual model of the system. Meteorological data was used to set up a stream temperature model. This study presents a unique example of an indirectly lake-headed stream, i.e., a lake that only has transient subsurface hydrologic connections to the stream and no surface connections. The interaction of groundwater and lake water, and the subsurface connectivity between the lake and the headwater spring determine the resulting stream temperature. Radiation dominated the non-advective fluxes in the stream energy balance. Sensible and latent heat fluxes play a secondary role, but their effects generally cancel out. During snowfall events, the latent heat associated with melting of direct snowfall onto the water surface was responsible for rapid stream cooling. An increase in advective inputs from groundwater and hillslope pathways did not result in observed cooling of stream water during rainfall events. The results from this study will assist water resource and fisheries managers in adapting to stream temperature changes under a warming climate.},
keywords = {},
pubstate = {published},
tppubtype = {article}
}
Stream thermal regimes are critical to the stability of freshwater habitats. There is growing concern that climate change will result in stream warming due to rising air temperatures, decreased shading in forested areas due to wildfires, and changes in streamflow. Groundwater plays an important role in controlling stream temperatures in mountain headwaters, where it makes up a considerable portion of discharge. This study investigated the controls on the thermal regime of a headwater stream, and the surrounding groundwater processes, in a catchment on the eastern slopes of the Canadian Rocky Mountains. Groundwater discharge to the headwater spring is partially sourced by a seasonal lake. Spring, stream, and lake temperature, water level, discharge and chemistry data were used to build a conceptual model of the system. Meteorological data was used to set up a stream temperature model. This study presents a unique example of an indirectly lake-headed stream, i.e., a lake that only has transient subsurface hydrologic connections to the stream and no surface connections. The interaction of groundwater and lake water, and the subsurface connectivity between the lake and the headwater spring determine the resulting stream temperature. Radiation dominated the non-advective fluxes in the stream energy balance. Sensible and latent heat fluxes play a secondary role, but their effects generally cancel out. During snowfall events, the latent heat associated with melting of direct snowfall onto the water surface was responsible for rapid stream cooling. An increase in advective inputs from groundwater and hillslope pathways did not result in observed cooling of stream water during rainfall events. The results from this study will assist water resource and fisheries managers in adapting to stream temperature changes under a warming climate.
Macedo, Jorge; Ramesh, Venkataraman; Liu, Chenying; Kottke, Albert
Evaluating Different Approaches for the Hazard‐Consistent Assessment of the Seismic Performance of Dams Journal Article
In: Bulletin of the Seismological Society of America, vol. 112, no. 3, pp. 1710–1726, 2022.
@article{journal1,
title = {Evaluating Different Approaches for the Hazard‐Consistent Assessment of the Seismic Performance of Dams},
author = {Jorge Macedo and Venkataraman Ramesh and Chenying Liu and Albert Kottke},
doi = {10.1785/0120210181},
year = {2022},
date = {2022-10-20},
urldate = {2022-10-27},
journal = {Bulletin of the Seismological Society of America},
volume = {112},
number = {3},
pages = {1710–1726},
abstract = {The current state of practice in the seismic assessment of dams relies on pseudoprobabilistic approaches in which the estimation of ground‐motion intensity measures (IMs) is decoupled from the estimation of seismically induced displacements (D). In contrast, in a performance‐based approach, which is gaining more popularity in practice, the entire IM hazard curve is used to provide displacement hazard curves (DHCs). Thus, engineers can directly estimate the displacement associated with a selected design hazard level, which is more consistent with performance‐based design concepts. This study evaluates different approaches to estimate D in performance‐based assessments that use D predictive equations, analytical D models, and advanced numerical modeling. To enable a comparison of different approaches under a hazard‐consistent D assessment, we propose using the conditional scenario spectra (CSS) framework to select ground motions that directly reproduce the IM hazard. We perform the evaluations by comparing DHCs for a rockfill dam using (1) the convolution of D predictive models and the IM hazard, (2) the CSS approach combined with dynamic analyses performed with analytical models (i.e., stick‐slip and transfer function models), and (3) the CSS approach combined with advance numerical modeling. The results show that the DHCs estimated from advanced numerical modeling are more conservative, which is associated with the inherent assumptions in D predictive equations or analytical D models formulated based on “Newmark‐type” calculations. Finally, we discuss the differences between the different approaches to estimate D and provide insights in the context of pseudoprobabilistic‐based estimates.},
keywords = {},
pubstate = {published},
tppubtype = {article}
}
The current state of practice in the seismic assessment of dams relies on pseudoprobabilistic approaches in which the estimation of ground‐motion intensity measures (IMs) is decoupled from the estimation of seismically induced displacements (D). In contrast, in a performance‐based approach, which is gaining more popularity in practice, the entire IM hazard curve is used to provide displacement hazard curves (DHCs). Thus, engineers can directly estimate the displacement associated with a selected design hazard level, which is more consistent with performance‐based design concepts. This study evaluates different approaches to estimate D in performance‐based assessments that use D predictive equations, analytical D models, and advanced numerical modeling. To enable a comparison of different approaches under a hazard‐consistent D assessment, we propose using the conditional scenario spectra (CSS) framework to select ground motions that directly reproduce the IM hazard. We perform the evaluations by comparing DHCs for a rockfill dam using (1) the convolution of D predictive models and the IM hazard, (2) the CSS approach combined with dynamic analyses performed with analytical models (i.e., stick‐slip and transfer function models), and (3) the CSS approach combined with advance numerical modeling. The results show that the DHCs estimated from advanced numerical modeling are more conservative, which is associated with the inherent assumptions in D predictive equations or analytical D models formulated based on “Newmark‐type” calculations. Finally, we discuss the differences between the different approaches to estimate D and provide insights in the context of pseudoprobabilistic‐based estimates.
Scully, Keelin; Laurenzi, Laura; Blackmore, Sharon; Harrison, Bevin; Adams, Marc
Faro Mine, Yukon: How Mass Balance Modelling Helped to 'Keep Clean Water Clean' Conference
International Conference on Acid Rock Drainage (ICARD), 2022.
@conference{nokey,
title = {Faro Mine, Yukon: How Mass Balance Modelling Helped to 'Keep Clean Water Clean'},
author = {Keelin Scully and Laura Laurenzi and Sharon Blackmore and Bevin Harrison and Marc Adams},
year = {2022},
date = {2022-10-13},
urldate = {2022-10-25},
booktitle = {International Conference on Acid Rock Drainage (ICARD)},
abstract = {The Faro Mine, located in the central Yukon, produced lead, zinc, silver, and gold from the late 1960s until 1998 when the mine was abandoned. Seepage from the storage of sulphidic waste in the Faro waste rock dumps (WRDs) has variably impacted groundwater and surface water reporting to the North Fork Rose Creek (NFRC), a fish-bearing surface water body, which flows along the toe of the Faro WRDs. Zinc is the primary parameter of concern for the NFRC. In 2014, the concentration of zinc reached just above 1 mg L-1 at a NFRC reference station downstream of the WRDs, which was several orders of magnitude higher than typical water quality guidelines for the protection of fresh-water aquatic life and previously observed yearly maximum concentrations. Beginning in 2016, the Government of Canada, represented by Crown-Indigenous Relations and Northern Affairs Canada (CIRNAC) commenced an Urgent Works project. The primary objective of the Urgent Works project was to “keep clean water clean”. To achieve this objective, the project was divided into: the non-contact Water Diversion Channel (NCWDC) and the contact water collection and conveyance system (CW System). The NFRC, upstream of the WRDs, was diverted into a hydraulically isolated channel (the NCWDC) which allowed for focused collection of WRD seepage by the CW System. For the CW System, a CW Interim Measure (CWIM) was commissioned, which focused on interception of shallow groundwater and surface flow in the NFRC channel bed. Mass balance models were developed for both the NCWDC and the CWIM to inform their design and predict performance. For the NCWDC, a mass balance model was used to simulate potential impacts from construction materials. For the CWIM, a mass balance model was used to assess design options, estimate load removal, and estimate residual downstream water quality. First year performance monitoring results from the CWIM show zinc concentrations in the intercepted contact water are within a factor of 2 of modelled predictions. Furthermore, measured zinc concentrations observed as of the end of 2021 at the downstream reference station are below the freshwater aquatic life guideline applied to the Urgent Works project.
},
keywords = {},
pubstate = {published},
tppubtype = {conference}
}
The Faro Mine, located in the central Yukon, produced lead, zinc, silver, and gold from the late 1960s until 1998 when the mine was abandoned. Seepage from the storage of sulphidic waste in the Faro waste rock dumps (WRDs) has variably impacted groundwater and surface water reporting to the North Fork Rose Creek (NFRC), a fish-bearing surface water body, which flows along the toe of the Faro WRDs. Zinc is the primary parameter of concern for the NFRC. In 2014, the concentration of zinc reached just above 1 mg L-1 at a NFRC reference station downstream of the WRDs, which was several orders of magnitude higher than typical water quality guidelines for the protection of fresh-water aquatic life and previously observed yearly maximum concentrations. Beginning in 2016, the Government of Canada, represented by Crown-Indigenous Relations and Northern Affairs Canada (CIRNAC) commenced an Urgent Works project. The primary objective of the Urgent Works project was to “keep clean water clean”. To achieve this objective, the project was divided into: the non-contact Water Diversion Channel (NCWDC) and the contact water collection and conveyance system (CW System). The NFRC, upstream of the WRDs, was diverted into a hydraulically isolated channel (the NCWDC) which allowed for focused collection of WRD seepage by the CW System. For the CW System, a CW Interim Measure (CWIM) was commissioned, which focused on interception of shallow groundwater and surface flow in the NFRC channel bed. Mass balance models were developed for both the NCWDC and the CWIM to inform their design and predict performance. For the NCWDC, a mass balance model was used to simulate potential impacts from construction materials. For the CWIM, a mass balance model was used to assess design options, estimate load removal, and estimate residual downstream water quality. First year performance monitoring results from the CWIM show zinc concentrations in the intercepted contact water are within a factor of 2 of modelled predictions. Furthermore, measured zinc concentrations observed as of the end of 2021 at the downstream reference station are below the freshwater aquatic life guideline applied to the Urgent Works project.
Adams, Marc; Scully, Keelin; Seto, Jack; Harrison, Bevin
Faro Mine, Yukon Territory, Canada: A Case Study for Optimising Zinc Load Capture by Clean Water Diversion and Focused Contact Water Capture Conference
Mine Closue 2022, 2022.
@conference{Conference1_109,
title = {Faro Mine, Yukon Territory, Canada: A Case Study for Optimising Zinc Load Capture by Clean Water Diversion and Focused Contact Water Capture},
author = {Marc Adams and Keelin Scully and Jack Seto and Bevin Harrison},
year = {2022},
date = {2022-10-12},
booktitle = {Mine Closue 2022},
abstract = {The Faro Mine, located in the central Yukon, produced lead, zinc, silver, and gold from the late 1960s until 1998, when the mine was abandoned. Seepage from sulfidic waste stored in the Faro waste rock dumps (WRDs) has variably impacted groundwater and surface water reporting to the North Fork of Rose Creek (NFRC), a fish-bearing surface water body, which passes along the toe of the Faro WRDs. Zinc is the primary parameter of concern, reaching several orders of magnitude higher than applicable water quality guidelines, and previous yearly maximum concentrations. Interception of contact water before it reaches the NFRC has been challenging due to the complex seepage patterns within the WRDs and proximity of the creek. Despite existing collection systems intercepting high concentration seepage pathways, zinc remained elevated in the creek. The NFRC Realignment Project commenced in 2015 to ‘keep clean water clean’ by diverting the NFRC into the non-contact water diversion channel (NCWDC) and allowing focused collection of WRD seepage in the remnant NFRC channel. The first phase of the contact water collection and conveyance system (CW System) was focused on the interception of shallow groundwater and surface flow in the remnant NFRC. The NCWDC was commissioned on24 October 2020, and the initial CW System was commissioned on 15 April 2021. Isolating the clean water through construction of the NCWDC substantially reduced the surface water available for dilution. Both the uncertainty in capturing contact water prior to it reaching the creek and the efficiency of capturing contact water once mixing occurred with creek flow were mitigated with this approach. A year after commissioning the NFRC Realignment Project, performance monitoring shows measured zinc concentrations in the NFRC approximately two orders of magnitude lower at the downstream monitoring station than realised by previous efforts.},
keywords = {},
pubstate = {published},
tppubtype = {conference}
}
The Faro Mine, located in the central Yukon, produced lead, zinc, silver, and gold from the late 1960s until 1998, when the mine was abandoned. Seepage from sulfidic waste stored in the Faro waste rock dumps (WRDs) has variably impacted groundwater and surface water reporting to the North Fork of Rose Creek (NFRC), a fish-bearing surface water body, which passes along the toe of the Faro WRDs. Zinc is the primary parameter of concern, reaching several orders of magnitude higher than applicable water quality guidelines, and previous yearly maximum concentrations. Interception of contact water before it reaches the NFRC has been challenging due to the complex seepage patterns within the WRDs and proximity of the creek. Despite existing collection systems intercepting high concentration seepage pathways, zinc remained elevated in the creek. The NFRC Realignment Project commenced in 2015 to ‘keep clean water clean’ by diverting the NFRC into the non-contact water diversion channel (NCWDC) and allowing focused collection of WRD seepage in the remnant NFRC channel. The first phase of the contact water collection and conveyance system (CW System) was focused on the interception of shallow groundwater and surface flow in the remnant NFRC. The NCWDC was commissioned on24 October 2020, and the initial CW System was commissioned on 15 April 2021. Isolating the clean water through construction of the NCWDC substantially reduced the surface water available for dilution. Both the uncertainty in capturing contact water prior to it reaching the creek and the efficiency of capturing contact water once mixing occurred with creek flow were mitigated with this approach. A year after commissioning the NFRC Realignment Project, performance monitoring shows measured zinc concentrations in the NFRC approximately two orders of magnitude lower at the downstream monitoring station than realised by previous efforts.
Scordo, Elisa; Williams, Haley; Lockwood, Kenneth; Holm, Kris; Carter, Richard
Filling in the Details: Base Level Flood Hazard Mapping as a Cost-Effective Tool for Floodplain Management Conference
CWRA 2022 National Conference: Valuing Shared Waters , 2022.
@conference{Conference1,
title = {Filling in the Details: Base Level Flood Hazard Mapping as a Cost-Effective Tool for Floodplain Management },
author = {Elisa Scordo and Haley Williams and Kenneth Lockwood and Kris Holm and Richard Carter},
year = {2022},
date = {2022-10-09},
urldate = {2022-10-09},
booktitle = {CWRA 2022 National Conference: Valuing Shared Waters },
abstract = {Detailed floodplain maps are an important tool for building flood-resilient communities, but they are often time and cost intensive to produce and are therefore generally undertaken in locations with recognized hazards or elements at risk. Due to these barriers, techniques have been developed by organizations responsible for flood management such as the Federal Emergency Management Association (FEMA) in the US, to produce more cost-effective flood maps for large areas at a screening-level of detail. “Base level” flood hazard mapping integrates high-resolution topographic data, an assessment of regional hydrology, and hydraulic modelling to develop hazard maps for multiple flood scenarios, including considerations for climate change. While not as accurate as maps produced by detailed flood mapping studies, these maps can be used as a planning tool for flood-prone communities and supplemented with detailed flood mapping once available. Base level flood mapping techniques were applied across several large rivers in British Columbia (BC) as part of regional-scale flood hazard studies conducted by BGC Engineering Inc. (BGC). Screening-level estimates of flood inundation extents, flood depths, and peak flow velocities were displayed in a web-based application developed by BGC called Cambio. These results were then used by local authorities in BC to identify, prioritize, and manage areas subject to riverine flood hazards in their communities.},
keywords = {},
pubstate = {published},
tppubtype = {conference}
}
Detailed floodplain maps are an important tool for building flood-resilient communities, but they are often time and cost intensive to produce and are therefore generally undertaken in locations with recognized hazards or elements at risk. Due to these barriers, techniques have been developed by organizations responsible for flood management such as the Federal Emergency Management Association (FEMA) in the US, to produce more cost-effective flood maps for large areas at a screening-level of detail. “Base level” flood hazard mapping integrates high-resolution topographic data, an assessment of regional hydrology, and hydraulic modelling to develop hazard maps for multiple flood scenarios, including considerations for climate change. While not as accurate as maps produced by detailed flood mapping studies, these maps can be used as a planning tool for flood-prone communities and supplemented with detailed flood mapping once available. Base level flood mapping techniques were applied across several large rivers in British Columbia (BC) as part of regional-scale flood hazard studies conducted by BGC Engineering Inc. (BGC). Screening-level estimates of flood inundation extents, flood depths, and peak flow velocities were displayed in a web-based application developed by BGC called Cambio. These results were then used by local authorities in BC to identify, prioritize, and manage areas subject to riverine flood hazards in their communities.
Hairabedian, Melissa; Coia, Vincenzo; Grover, Patrick
Flood Frequency-Magnitude Relationship for the Coldwater River Conference
CWRA 2022 National Conference: Valuing Shared Waters , 2022.
@conference{Conference1,
title = {Flood Frequency-Magnitude Relationship for the Coldwater River },
author = {Melissa Hairabedian and Vincenzo Coia and Patrick Grover},
year = {2022},
date = {2022-10-07},
urldate = {2022-10-07},
booktitle = {CWRA 2022 National Conference: Valuing Shared Waters },
abstract = {The landfalling of an Atmospheric River (AR) mid-November 2021 resulted in an extreme flood event in the Coast Mountains of British Columbia. A review of historical flood events recorded at the Coldwater River at Brookmere (08LG048) hydrometric station shows that ARs coincide with 7 of the 10 largest flood events. The hydrologic regime in the Coldwater River watershed is nival-pluvial with the annual peak flood typically occurring from snowmelt in the spring. In some years, ARs in the fall and winter months can generate large magnitude floods exceeding the snowmelt flood in the spring. Flood events that coincide with ARs can exert an important control on the distribution of extreme flood events. The goal of this study was to estimate the design flood to inform mitigation and re-construction efforts. Standard practice is to use the annual maximum series (AMS) and fit a statistical distribution. In this study, the design flood was estimated using a statistical approach where both snowmelt- and AR-coinciding flood events were modelled separately. The statistical models were subsequently compounded honouring each annual probability of occurrence. Results show that the compounded model has a heavier tail than the standard practice model, and a larger design flood. Although the compounded model does not improve the confidence bounds, its increased flexibility reduces bias, especially for longer return periods due to its heavier tail. Failing to account for both hydrologic processes separately could result in an underestimation of the design flood and compromise long-term flood protection.},
keywords = {},
pubstate = {published},
tppubtype = {conference}
}
The landfalling of an Atmospheric River (AR) mid-November 2021 resulted in an extreme flood event in the Coast Mountains of British Columbia. A review of historical flood events recorded at the Coldwater River at Brookmere (08LG048) hydrometric station shows that ARs coincide with 7 of the 10 largest flood events. The hydrologic regime in the Coldwater River watershed is nival-pluvial with the annual peak flood typically occurring from snowmelt in the spring. In some years, ARs in the fall and winter months can generate large magnitude floods exceeding the snowmelt flood in the spring. Flood events that coincide with ARs can exert an important control on the distribution of extreme flood events. The goal of this study was to estimate the design flood to inform mitigation and re-construction efforts. Standard practice is to use the annual maximum series (AMS) and fit a statistical distribution. In this study, the design flood was estimated using a statistical approach where both snowmelt- and AR-coinciding flood events were modelled separately. The statistical models were subsequently compounded honouring each annual probability of occurrence. Results show that the compounded model has a heavier tail than the standard practice model, and a larger design flood. Although the compounded model does not improve the confidence bounds, its increased flexibility reduces bias, especially for longer return periods due to its heavier tail. Failing to account for both hydrologic processes separately could result in an underestimation of the design flood and compromise long-term flood protection.
Whittall, John; Porter, Mike; Kinakin, Derek
Frequency-Magnitude Relationships for Open Pit Slope Failures Conference
Slope Stability 2022, 2022.
@conference{Conference1,
title = {Frequency-Magnitude Relationships for Open Pit Slope Failures },
author = {John Whittall and Mike Porter and Derek Kinakin},
year = {2022},
date = {2022-10-05},
urldate = {2022-10-05},
booktitle = {Slope Stability 2022},
keywords = {},
pubstate = {published},
tppubtype = {conference}
}
Scheip, Corey; Lato, Matthew
From Network-Scale Hazard Mapping to Site-Specific Remediation: How Advances in Lidar Change Detection are Changing Pipeline Integrity Management Conference
Pipeline Technology Forum and Pipeline Opportunities Conference, 2022.
@conference{Conference1,
title = {From Network-Scale Hazard Mapping to Site-Specific Remediation: How Advances in Lidar Change Detection are Changing Pipeline Integrity Management},
author = {Corey Scheip and Matthew Lato},
year = {2022},
date = {2022-10-03},
urldate = {2022-10-03},
booktitle = {Pipeline Technology Forum and Pipeline Opportunities Conference},
abstract = {How advances in lidar change detection are changing pipeline integrity management.},
keywords = {},
pubstate = {published},
tppubtype = {conference}
}
How advances in lidar change detection are changing pipeline integrity management.
Arenson, Lukas
Geohazard Management in Permafrost Regions Conference
Proceedings of the 8th Canadian Conference on Geotechnique and Natural Hazards: Innovative geoscience for tomorrow, 2022.
@conference{Conference1,
title = {Geohazard Management in Permafrost Regions},
author = {Lukas Arenson},
year = {2022},
date = {2022-09-28},
urldate = {2022-09-28},
booktitle = {Proceedings of the 8th Canadian Conference on Geotechnique and Natural Hazards: Innovative geoscience for tomorrow},
pages = {47-56},
abstract = {Landscapes in permafrost regions are changing at unprecedented rates. In the Arctic and the Sub-Arctic, changes in environmental conditions in response to climate change have significant impacts on the permafrost resulting in the development of processes that had either not been observed in the past or exhibit unprecedented changes in their frequencies and magnitudes. These changes alter the hazard potential significantly, impacting the risk to infrastructure. It is therefore no longer adequate to complete a geohazard assessment by documenting historic events and assuming that future processes will be similar. A process-based risk assessment approach is therefore required. On the other hand, significant uncertainties exist in these processes, and it would not be economic to adapt all infrastructure in permafrost regions to withstand impacts that are based on worst case scenarios. Monitoring in combination with a warning system offers an economic approach for managing geohazards in permafrost regions that not only assists in reducing potential consequences, but also allows to continuously improve the understanding of the natural process and specifically, geohazard triggering mechanisms. Recent advances in monitoring and communication technologies as well as data management systems provide new opportunities but also challenges. Based on two case studies, values, and limitations of geohazard monitoring and management systems are discussed.},
keywords = {},
pubstate = {published},
tppubtype = {conference}
}
Landscapes in permafrost regions are changing at unprecedented rates. In the Arctic and the Sub-Arctic, changes in environmental conditions in response to climate change have significant impacts on the permafrost resulting in the development of processes that had either not been observed in the past or exhibit unprecedented changes in their frequencies and magnitudes. These changes alter the hazard potential significantly, impacting the risk to infrastructure. It is therefore no longer adequate to complete a geohazard assessment by documenting historic events and assuming that future processes will be similar. A process-based risk assessment approach is therefore required. On the other hand, significant uncertainties exist in these processes, and it would not be economic to adapt all infrastructure in permafrost regions to withstand impacts that are based on worst case scenarios. Monitoring in combination with a warning system offers an economic approach for managing geohazards in permafrost regions that not only assists in reducing potential consequences, but also allows to continuously improve the understanding of the natural process and specifically, geohazard triggering mechanisms. Recent advances in monitoring and communication technologies as well as data management systems provide new opportunities but also challenges. Based on two case studies, values, and limitations of geohazard monitoring and management systems are discussed.
de Guzman, Earl; Alfaro, Marolo; Arenson, Lukas; Dore, Guy
Geosynthetic-Reinforced Embankment in Cold Regions: Observations and Numerical Simulations Journal Article
In: Geosynthetics International, 2022.
@article{article1,
title = {Geosynthetic-Reinforced Embankment in Cold Regions: Observations and Numerical Simulations },
author = {Earl de Guzman and Marolo Alfaro and Lukas Arenson and Guy Dore},
doi = {10.1680/jgein.21.00088},
year = {2022},
date = {2022-09-27},
urldate = {2022-09-27},
journal = {Geosynthetics International},
abstract = {An embankment underlain by permafrost foundation was reinforced with wicking woven geotextiles at its side slopes to reduce slope displacements when the fill material that was compacted at frozen condition thaws during subsequent spring and summer seasons following winter construction. The embankment fill and permafrost foundation were instrumented with thermistor strings to monitor soil temperatures as well as ShapeAccelArrays installed at the mid-slope of the embankment to measure displacements. A numerical model was developed in a commercially-available finite element software to simulate the thermal and mechanical behaviour of this embankment and further understand the benefit of using woven geotextiles in cold regions. A sequentially-coupled approach was used where temperature-dependent mechanical properties were invoked based on a heat transfer analysis. Four years of monitored results from the reinforced embankment were used to calibrate the numerical model. An adjacent section of the embankment without the geotextiles was also modelled and results show a significant reduction in slope displacements. The monitored performance and the model results presented will improve the design guidelines for embankments in cold regions using geotextiles.},
keywords = {},
pubstate = {published},
tppubtype = {article}
}
An embankment underlain by permafrost foundation was reinforced with wicking woven geotextiles at its side slopes to reduce slope displacements when the fill material that was compacted at frozen condition thaws during subsequent spring and summer seasons following winter construction. The embankment fill and permafrost foundation were instrumented with thermistor strings to monitor soil temperatures as well as ShapeAccelArrays installed at the mid-slope of the embankment to measure displacements. A numerical model was developed in a commercially-available finite element software to simulate the thermal and mechanical behaviour of this embankment and further understand the benefit of using woven geotextiles in cold regions. A sequentially-coupled approach was used where temperature-dependent mechanical properties were invoked based on a heat transfer analysis. Four years of monitored results from the reinforced embankment were used to calibrate the numerical model. An adjacent section of the embankment without the geotextiles was also modelled and results show a significant reduction in slope displacements. The monitored performance and the model results presented will improve the design guidelines for embankments in cold regions using geotextiles.
Willis, Sarah
Granular Filter Design and Performance Considerations for Aging Embankment Dams Masters Thesis
2022.
@mastersthesis{Thesis1,
title = {Granular Filter Design and Performance Considerations for Aging Embankment Dams},
author = {Sarah Willis},
doi = {10.7939/r3-abg4-ag41},
year = {2022},
date = {2022-09-23},
urldate = {2022-09-23},
abstract = {Embankment dams have been constructed in Canada and the United States for over one hundred years. Embankment dams are owned by government bodies, mining and resource companies, hydroelectric producers, and other entities. Dams that have been in service for many years may have a high hazard rating due to the consequences of potential failure, as development tends to expand towards these structures over time. Older embankment dams precede the development of modern filter design criteria, which were first developed in the 1920s and have undergone considerable progress and refinement since. The lack of appropriate filter design in aging dams may increase risk of internal erosion and eventual failure. Risk assessment procedures and monitoring programs are the primary tools used by dam owners and operators to evaluate the risk of and detect potential failure events. A brief summary of modern filter design has been presented. Traditional particle-sized based criteria were reviewed and recent developments in constriction-based criteria were discussed. Considerations for challenging base soils, such as dispersive and broadly graded soils, were provided. The effects of aging on dam filter properties and performance were discussed. Evidence of filter degradation over time exists in the literature and has been attributed to several causes. These factors include filter clogging, changes in water quality, mechanical degradation, and the development of internal instability and each has been examined. A discussion of risk assessment and monitoring for aging dams has been provided. Three of the most widely-used methods were summarized. Most risk assessment methods use a potential failure mode analysis framework. The numerous uncertainties associated with an aging structure presents challenges when attempting to apply potential failure mode analysis. The results of a risk assessment investigation are typically used to identify areas that may require additional investigation, potential remediation actions, or increased monitoring. They are also used as a basis for emergency planning. Monitoring techniques provide information about the location and rate of seepage in and through the embankment. Monitoring is typically the first indication of an internal erosion event that may lead to failure. Improvements in monitoring techniques have decreased detection time and increase likelihood of successful interventions that prevent failure.},
keywords = {},
pubstate = {published},
tppubtype = {mastersthesis}
}
Embankment dams have been constructed in Canada and the United States for over one hundred years. Embankment dams are owned by government bodies, mining and resource companies, hydroelectric producers, and other entities. Dams that have been in service for many years may have a high hazard rating due to the consequences of potential failure, as development tends to expand towards these structures over time. Older embankment dams precede the development of modern filter design criteria, which were first developed in the 1920s and have undergone considerable progress and refinement since. The lack of appropriate filter design in aging dams may increase risk of internal erosion and eventual failure. Risk assessment procedures and monitoring programs are the primary tools used by dam owners and operators to evaluate the risk of and detect potential failure events. A brief summary of modern filter design has been presented. Traditional particle-sized based criteria were reviewed and recent developments in constriction-based criteria were discussed. Considerations for challenging base soils, such as dispersive and broadly graded soils, were provided. The effects of aging on dam filter properties and performance were discussed. Evidence of filter degradation over time exists in the literature and has been attributed to several causes. These factors include filter clogging, changes in water quality, mechanical degradation, and the development of internal instability and each has been examined. A discussion of risk assessment and monitoring for aging dams has been provided. Three of the most widely-used methods were summarized. Most risk assessment methods use a potential failure mode analysis framework. The numerous uncertainties associated with an aging structure presents challenges when attempting to apply potential failure mode analysis. The results of a risk assessment investigation are typically used to identify areas that may require additional investigation, potential remediation actions, or increased monitoring. They are also used as a basis for emergency planning. Monitoring techniques provide information about the location and rate of seepage in and through the embankment. Monitoring is typically the first indication of an internal erosion event that may lead to failure. Improvements in monitoring techniques have decreased detection time and increase likelihood of successful interventions that prevent failure.
Sturzenegger, Matthieu; Jakob, Matthias; Arenson, Lukas; Mitchell, Andrew; Harrington, Jordan; Collier-Pandya, Beatrice; Ondercin, Matthew; Suszek, Naia; Bond, Jeffrey
Hazard and Risk of the Moosehide Slide (Ëddhä̀ dä̀dhëchą), Dawson City, Yukon Conference
GeoCalgary, 2022.
@conference{Conference1,
title = {Hazard and Risk of the Moosehide Slide (Ëddhä̀ dä̀dhëchą), Dawson City, Yukon },
author = {Matthieu Sturzenegger and Matthias Jakob and Lukas Arenson and Andrew Mitchell and Jordan Harrington and Beatrice Collier-Pandya and Matthew Ondercin and Naia Suszek and Jeffrey Bond},
year = {2022},
date = {2022-09-21},
urldate = {2022-09-21},
booktitle = {GeoCalgary},
abstract = {The Moosehide Slide is a rockslide located on the northern margins of Dawson City, Yukon. It features a prominent headscarp, corresponding to the initiation zone of a pre-historic landslide. Field evidence, such as tension cracks and tension-split trees, and airborne lidar change detection analysis indicate retrogressive instability in the headscarp zone. This paper summarizes the steps completed to quantify landslide hazard and risk associated with a potential rock avalanche with possible runout to the north end of Dawson City. The steps completed include i) quantification of potential source volumes and hazard probabilities at the headscarp; ii) modelling of the rock avalanche runout characteristics; iii) assessment of the influence of permafrost degradation on the likelihood and intensity of the rock avalanche; and iv) quantitative risk assessment in both existing and potential future developments at the north end of Dawson City. The results are integrated in two types of maps for communication of landslide hazard and risk to the public and decision makers. These maps form the basis for the development of a monitoring program and emergency response plan to mitigate life-loss risk in existing developments.},
keywords = {},
pubstate = {published},
tppubtype = {conference}
}
The Moosehide Slide is a rockslide located on the northern margins of Dawson City, Yukon. It features a prominent headscarp, corresponding to the initiation zone of a pre-historic landslide. Field evidence, such as tension cracks and tension-split trees, and airborne lidar change detection analysis indicate retrogressive instability in the headscarp zone. This paper summarizes the steps completed to quantify landslide hazard and risk associated with a potential rock avalanche with possible runout to the north end of Dawson City. The steps completed include i) quantification of potential source volumes and hazard probabilities at the headscarp; ii) modelling of the rock avalanche runout characteristics; iii) assessment of the influence of permafrost degradation on the likelihood and intensity of the rock avalanche; and iv) quantitative risk assessment in both existing and potential future developments at the north end of Dawson City. The results are integrated in two types of maps for communication of landslide hazard and risk to the public and decision makers. These maps form the basis for the development of a monitoring program and emergency response plan to mitigate life-loss risk in existing developments.
Franklin, Kathryn; MacInnis, Chris; Roca, Joan; Magnusson, Gerald; Burton, Bill; Enos, Nick
Holographic Models of Closure Landscapes for Stakeholder Engagement: When You Need More Than Words and Pictures Conference
Mine Closure 2022, 2022.
@conference{Conference1,
title = {Holographic Models of Closure Landscapes for Stakeholder Engagement: When You Need More Than Words and Pictures},
author = {Kathryn Franklin and Chris MacInnis and Joan Roca and Gerald Magnusson and Bill Burton and Nick Enos},
year = {2022},
date = {2022-09-19},
urldate = {2022-09-19},
booktitle = {Mine Closure 2022},
abstract = {The Giant Mine Remediation Project (Giant) and Faro Mine Remediation Project (Faro) are abandoned mine projects in northern Canada with long legacies and many complex challenges. BGC Engineering Inc. has been working with Crown-Indigenous Relations and Northern Affairs (CIRNAC) using holographic projections to collaborate with First Nations and local communities on key mine closure information. This paper shares experience with using Microsoft’s mixed reality HoloLens devices (HoloLens) as a tool that creates a safe and equitable environment to collaboratively engage with communities where previous experience and technical understanding are not prerequisites to contributing. This is important, as engaging in meaningful discussions involving mine closure planning involves effectively communicating engineering and earth science information to rights holders and stakeholders with diverse experiences. The Faro project is beginning to develop several 3D digital models to encourage conversation, discussion, and engagement on the progress of mine closure, showcasing a time lapse of how the mine has changed over the past few years and its current state, and to explore the staged approach to reclamation. HoloLens was used to incorporate a broad spectrum of data into holographic models that were shared with multiple users to experience together. The digital models incorporated historical topographic and aerial imagery and current conditions, and include proposed future conditions based on designs and reclamation plans. The participants can collaboratively experience this collated information from different viewpoints, including in tabletop models, as 3D objects in the middle of the room, and as immersive 3D scenes. At Giant, there is a complex underground mining legacy that the community wanted to better understand. Holographic models were created that allow users to visualise and walk around the surface and underground together, as a community, and ask questions, voice concerns and ideas, and see how groundwater conditions change throughout the seasons and into the future. Additionally, as there are several locations throughout the mine that will be reclaimed based on input from the community, it is important to be able to visualise the design beyond 2D engineering-based drawings. Real-life-scale immersive views were created, providing experiences of how these areas might look once reclamation is finished. We hope that by sharing the experience of sharing information in this way that the state of practice for creating holistic and sustainable mine closure designs that reflect the input of rights holders and stakeholders can be advanced.},
keywords = {},
pubstate = {published},
tppubtype = {conference}
}
The Giant Mine Remediation Project (Giant) and Faro Mine Remediation Project (Faro) are abandoned mine projects in northern Canada with long legacies and many complex challenges. BGC Engineering Inc. has been working with Crown-Indigenous Relations and Northern Affairs (CIRNAC) using holographic projections to collaborate with First Nations and local communities on key mine closure information. This paper shares experience with using Microsoft’s mixed reality HoloLens devices (HoloLens) as a tool that creates a safe and equitable environment to collaboratively engage with communities where previous experience and technical understanding are not prerequisites to contributing. This is important, as engaging in meaningful discussions involving mine closure planning involves effectively communicating engineering and earth science information to rights holders and stakeholders with diverse experiences. The Faro project is beginning to develop several 3D digital models to encourage conversation, discussion, and engagement on the progress of mine closure, showcasing a time lapse of how the mine has changed over the past few years and its current state, and to explore the staged approach to reclamation. HoloLens was used to incorporate a broad spectrum of data into holographic models that were shared with multiple users to experience together. The digital models incorporated historical topographic and aerial imagery and current conditions, and include proposed future conditions based on designs and reclamation plans. The participants can collaboratively experience this collated information from different viewpoints, including in tabletop models, as 3D objects in the middle of the room, and as immersive 3D scenes. At Giant, there is a complex underground mining legacy that the community wanted to better understand. Holographic models were created that allow users to visualise and walk around the surface and underground together, as a community, and ask questions, voice concerns and ideas, and see how groundwater conditions change throughout the seasons and into the future. Additionally, as there are several locations throughout the mine that will be reclaimed based on input from the community, it is important to be able to visualise the design beyond 2D engineering-based drawings. Real-life-scale immersive views were created, providing experiences of how these areas might look once reclamation is finished. We hope that by sharing the experience of sharing information in this way that the state of practice for creating holistic and sustainable mine closure designs that reflect the input of rights holders and stakeholders can be advanced.
Lau, Carie-Ann; Jakob, Matthias; Baumgard, Alex; Rios, Andy; Brayshaw, Drew; Brugman, Melinda; Millard, Tom; Giblin, Liam
Hydro-Geomorphic Effects of the November 2021 Atmospheric Rivers on Infrastructure in Southwestern British Columbia Conference
Proceedings of the 8th Canadian Conference on Geotechnique and Natural Hazards: Innovative geoscience for tomorrow, 2022.
@conference{Conference1,
title = {Hydro-Geomorphic Effects of the November 2021 Atmospheric Rivers on Infrastructure in Southwestern British Columbia},
author = {Carie-Ann Lau and Matthias Jakob and Alex Baumgard and Andy Rios and Drew Brayshaw and Melinda Brugman and Tom Millard and Liam Giblin},
year = {2022},
date = {2022-09-16},
urldate = {2022-09-01},
booktitle = {Proceedings of the 8th Canadian Conference on Geotechnique and Natural Hazards: Innovative geoscience for tomorrow},
abstract = {From mid to late November 2021, southwestern British Columbia was affected by a series of atmospheric rivers that caused widespread flooding, bank erosion, and shallow landslides. Critical infrastructure was damaged across the southwestern portions of the province involving highways, pipelines, transmission lines, and railways. In addition, landslides impacted some homes on, or below, steep slopes. We describe the development, meteorology, intensity, and duration of the atmospheric rivers including rainfall and snowmelt and their relationship to observed flood magnitudes. Debris flows and debris floods (including post-wildfire events), shallow landslides, flooding, bank erosion, and avulsions that affected infrastructure corridors are mapped. We examine the failure mechanisms of critical infrastructure and provide general guidance on shifting from a standard-based design approach towards a fully risk-based design approach.},
keywords = {},
pubstate = {published},
tppubtype = {conference}
}
From mid to late November 2021, southwestern British Columbia was affected by a series of atmospheric rivers that caused widespread flooding, bank erosion, and shallow landslides. Critical infrastructure was damaged across the southwestern portions of the province involving highways, pipelines, transmission lines, and railways. In addition, landslides impacted some homes on, or below, steep slopes. We describe the development, meteorology, intensity, and duration of the atmospheric rivers including rainfall and snowmelt and their relationship to observed flood magnitudes. Debris flows and debris floods (including post-wildfire events), shallow landslides, flooding, bank erosion, and avulsions that affected infrastructure corridors are mapped. We examine the failure mechanisms of critical infrastructure and provide general guidance on shifting from a standard-based design approach towards a fully risk-based design approach.
Déri-Takács, Judit; Rostron, Benjamin; Mendoza, Carl; Madlener, Reinhard
Hydrogeochemical Characteristics Refine the Conceptual Model of Groundwater Flow Wood Buffalo National Park, Canada Journal Article
In: Water, vol. 14, no. 6, 2022.
@article{article1,
title = {Hydrogeochemical Characteristics Refine the Conceptual Model of Groundwater Flow Wood Buffalo National Park, Canada},
author = {Judit Déri-Takács and Benjamin Rostron and Carl Mendoza and Reinhard Madlener},
doi = {10.3390/w14060965},
year = {2022},
date = {2022-09-15},
journal = {Water},
volume = {14},
number = {6},
abstract = {Wood Buffalo National Park (WBNP), the largest national park of Canada, has unique and complex ecosystems that depend on specific water quantity and quality. We characterize groundwaters and surface waters in WBNP by determining their chemical compositions and water types, the dominant hydrochemical processes affecting their compositions, and their hydrochemical characteristics in relation to interpreted groundwater flow systems. Total Dissolved Solid concentrations in groundwaters and surface waters range from ≤10 mg/L to ≥300,000 mg/L. Four distinct water type groups are found (1) Ca-SO4-type waters occur in multiple clusters across the area in outcrop areas of Devonian evaporites; (2) Na-Cl-type waters predominantly occur in the Salt plains region along the central eastern boundary, overlapping evaporite and carbonate-dominated bedrock formations; (3) Ca-HCO3-type waters dominate the Peace-Athabasca Delta-region in the south and most of the central region; and (4) “mixed” waters. Solutes in the waters originate from three main processes dissolution of halite, dissolution of sulphate minerals, and dissolution of carbonates. The spatial occurrence of hydrochemical characteristics correlate with hypothesized groundwater flow systems, i.e., Ca-SO4 and Na-Cl-type waters coincide with discharge areas of intermediate to regional groundwater flow paths, and Ca-HCO3-type waters overlap with recharge areas. The findings of this study contribute to advancing knowledge on the hydrochemical characteristics of this remote and highly protected region of Alberta, Canada, and are important components of any further, comprehensive assessment of the natural water conditions.},
keywords = {},
pubstate = {published},
tppubtype = {article}
}
Wood Buffalo National Park (WBNP), the largest national park of Canada, has unique and complex ecosystems that depend on specific water quantity and quality. We characterize groundwaters and surface waters in WBNP by determining their chemical compositions and water types, the dominant hydrochemical processes affecting their compositions, and their hydrochemical characteristics in relation to interpreted groundwater flow systems. Total Dissolved Solid concentrations in groundwaters and surface waters range from ≤10 mg/L to ≥300,000 mg/L. Four distinct water type groups are found (1) Ca-SO4-type waters occur in multiple clusters across the area in outcrop areas of Devonian evaporites; (2) Na-Cl-type waters predominantly occur in the Salt plains region along the central eastern boundary, overlapping evaporite and carbonate-dominated bedrock formations; (3) Ca-HCO3-type waters dominate the Peace-Athabasca Delta-region in the south and most of the central region; and (4) “mixed” waters. Solutes in the waters originate from three main processes dissolution of halite, dissolution of sulphate minerals, and dissolution of carbonates. The spatial occurrence of hydrochemical characteristics correlate with hypothesized groundwater flow systems, i.e., Ca-SO4 and Na-Cl-type waters coincide with discharge areas of intermediate to regional groundwater flow paths, and Ca-HCO3-type waters overlap with recharge areas. The findings of this study contribute to advancing knowledge on the hydrochemical characteristics of this remote and highly protected region of Alberta, Canada, and are important components of any further, comprehensive assessment of the natural water conditions.
Strouth, Alex; McDougall, Scott
Individual Risk Evaluation for Landslides: Key Details Journal Article
In: Landslides, vol. 19, no. 4, pp. 977-991, 2022.
@article{article1,
title = {Individual Risk Evaluation for Landslides: Key Details},
author = {Alex Strouth and Scott McDougall},
doi = {10.1007/s10346-021-01838-8},
year = {2022},
date = {2022-08-30},
urldate = {2022-08-26},
journal = {Landslides},
volume = {19},
number = {4},
pages = {977-991},
abstract = {Risk-taking is an essential part of life. As individuals, we evaluate risks intuitively and often subconsciously by comparing the perceived risks with expected benefits. We do this so commonly that it passes unnoticed, like when we decide to speed home from work or go for a swim. The comparison changes, however, when one entity (such as a government) imposes a risk evaluation on another person. For example, in a quantitative risk management framework, the estimated risk is compared with a tolerable risk threshold to decide if the person is ‘safe enough’. Landslide risk management methods are well established and there is consensus on tolerable life-loss risk thresholds. However, beneath this consensus lie several key details that are explored by this article, along with suggestions for refinement. Specifically, we suggest using the risk unit, micromort (one micromort equals a life loss risk of 1 in 1 million), in describing risk estimates and thresholds, to improve risk communication. For risk estimation, we provide guidance for defining and combining landslide scenarios and for recognizing where unquantified risk from low-probability/high-consequence scenarios ought to inform risk management decisions. For risk tolerance thresholds, we highlight the pitfalls of selecting unachievably low thresholds and suggest that there is no single universal threshold. Additionally, we argue that gross disproportion between costs and benefits of further risk reduction, which is integral to the As Low As Reasonably Practicable (ALARP) principle, is a commonly unachievable and counter-productive condition for risk tolerance, and other conditions centered on proportionality often apply. Finally, we provide several figures that can be used as risk communication tools, to provide context for risk estimates and risk tolerance thresholds when these values are reported to decision makers and the public.},
keywords = {},
pubstate = {published},
tppubtype = {article}
}
Risk-taking is an essential part of life. As individuals, we evaluate risks intuitively and often subconsciously by comparing the perceived risks with expected benefits. We do this so commonly that it passes unnoticed, like when we decide to speed home from work or go for a swim. The comparison changes, however, when one entity (such as a government) imposes a risk evaluation on another person. For example, in a quantitative risk management framework, the estimated risk is compared with a tolerable risk threshold to decide if the person is ‘safe enough’. Landslide risk management methods are well established and there is consensus on tolerable life-loss risk thresholds. However, beneath this consensus lie several key details that are explored by this article, along with suggestions for refinement. Specifically, we suggest using the risk unit, micromort (one micromort equals a life loss risk of 1 in 1 million), in describing risk estimates and thresholds, to improve risk communication. For risk estimation, we provide guidance for defining and combining landslide scenarios and for recognizing where unquantified risk from low-probability/high-consequence scenarios ought to inform risk management decisions. For risk tolerance thresholds, we highlight the pitfalls of selecting unachievably low thresholds and suggest that there is no single universal threshold. Additionally, we argue that gross disproportion between costs and benefits of further risk reduction, which is integral to the As Low As Reasonably Practicable (ALARP) principle, is a commonly unachievable and counter-productive condition for risk tolerance, and other conditions centered on proportionality often apply. Finally, we provide several figures that can be used as risk communication tools, to provide context for risk estimates and risk tolerance thresholds when these values are reported to decision makers and the public.
Mitchell, Andrew; Allstadt, Kate; George, David; Aaron, Jordan; McDougall, Scott; Moore, Jeffrey; Menounos, Brian
Insights on Multistage Rock Avalanche Behavior from Runout Modeling Constrained by Seismic Inversions Journal Article
In: Journal of Geophysical Research: Solid Earth, vol. 127, no. 10, 2022.
@article{journal1,
title = {Insights on Multistage Rock Avalanche Behavior from Runout Modeling Constrained by Seismic Inversions},
author = {Andrew Mitchell and Kate Allstadt and David George and Jordan Aaron and Scott McDougall and Jeffrey Moore and Brian Menounos},
doi = {10.1029/2021JB023444},
year = {2022},
date = {2022-08-26},
urldate = {2022-08-26},
journal = {Journal of Geophysical Research: Solid Earth},
volume = {127},
number = {10},
abstract = {Inversion of low-frequency regional seismic records to solve for a time series of bulk forces exerted on the earth by a landslide (a force-time function) is increasingly being used to infer volumes and dynamics of large, highly energetic landslides, such as rock avalanches and flowslides, and to provide calibration information on event dynamics and volumes for numerical landslide runout models. Much of the work to date using landslide runout modeling constrained by seismic data has focused on using single-phase models with frictional or velocity-weakening rheologies. Awareness of multistage landslide initiations is increasing, with discrete failures separated in time contributing to the final impact of an event. Our work utilizes a method for incorporating seismic data as a calibration constraint for landslide runout models, considering variable rheologies and different initiation conditions. This study presents a systematic examination of multiple rheologies and initiation conditions, and shows how these factors affect the force-time function derived from the landslide runout model. Our work confirms that, while rheology and fragmenting or initially coherent initiations affect the force-time function, multiple collapses separated by tens of seconds have the greatest impact on the shape and amplitude. We apply this method to the analysis of three real rock avalanches to better constrain plausible initiation conditions and rheology parameters using both seismic and field data. This study provides insights on how assumptions about the initiation dynamics of the source zone and the runout model definition can aid in the interpretation of seismic inversions for multistage rock avalanches.},
keywords = {},
pubstate = {published},
tppubtype = {article}
}
Inversion of low-frequency regional seismic records to solve for a time series of bulk forces exerted on the earth by a landslide (a force-time function) is increasingly being used to infer volumes and dynamics of large, highly energetic landslides, such as rock avalanches and flowslides, and to provide calibration information on event dynamics and volumes for numerical landslide runout models. Much of the work to date using landslide runout modeling constrained by seismic data has focused on using single-phase models with frictional or velocity-weakening rheologies. Awareness of multistage landslide initiations is increasing, with discrete failures separated in time contributing to the final impact of an event. Our work utilizes a method for incorporating seismic data as a calibration constraint for landslide runout models, considering variable rheologies and different initiation conditions. This study presents a systematic examination of multiple rheologies and initiation conditions, and shows how these factors affect the force-time function derived from the landslide runout model. Our work confirms that, while rheology and fragmenting or initially coherent initiations affect the force-time function, multiple collapses separated by tens of seconds have the greatest impact on the shape and amplitude. We apply this method to the analysis of three real rock avalanches to better constrain plausible initiation conditions and rheology parameters using both seismic and field data. This study provides insights on how assumptions about the initiation dynamics of the source zone and the runout model definition can aid in the interpretation of seismic inversions for multistage rock avalanches.
Scheip, Corey; Wegmann, Karl
Insights on the Growth and Mobility of Debris Flows from Repeat High-Resolution Lidar Journal Article
In: Landslides, vol. 19, no. 6, pp. 1297-1319, 2022.
@article{article1,
title = {Insights on the Growth and Mobility of Debris Flows from Repeat High-Resolution Lidar},
author = {Corey Scheip and Karl Wegmann},
doi = {10.1007/s10346-022-01862-2},
year = {2022},
date = {2022-08-25},
urldate = {2022-08-25},
journal = {Landslides},
volume = {19},
number = {6},
pages = {1297-1319},
abstract = {How debris flows erode and deposit material along their paths is difficult to determine in natural settings due to the lack of warning and the rapid pace at which they occur. Post-event field measurements or controlled flume experi-ments are commonly used to evaluate debris flows between the head and the distalmost deposit. Increasingly available high-resolution lidar data provide another means to evaluate the entrainment and deposition of material during a debris flow. This study utilizes submeter lidar before and after a debris flow event in Polk County, North Carolina, to evaluate for volumet-ric growth and decay of 54 rainfall-triggered debris flows that occurred during a convective storm on May 18, 2018. Debris flow evolution can be characterized by three discrete phases when viewed according to a volume-distance plot: (1) the initiating debris slide, (2) the entrainment phase, and (3) the depositional phase. The rate of debris flow growth is highest during the first phase, nearly linear during the second, and negative during the third phase. When normalized by distance along the flow, the growth rate decays according to a power law E=aXb ( r2≥0.97 ) . This new power law relationship may indicate differences in initiating landslide process and should be leveraged in future runout modeling studies.},
keywords = {},
pubstate = {published},
tppubtype = {article}
}
How debris flows erode and deposit material along their paths is difficult to determine in natural settings due to the lack of warning and the rapid pace at which they occur. Post-event field measurements or controlled flume experi-ments are commonly used to evaluate debris flows between the head and the distalmost deposit. Increasingly available high-resolution lidar data provide another means to evaluate the entrainment and deposition of material during a debris flow. This study utilizes submeter lidar before and after a debris flow event in Polk County, North Carolina, to evaluate for volumet-ric growth and decay of 54 rainfall-triggered debris flows that occurred during a convective storm on May 18, 2018. Debris flow evolution can be characterized by three discrete phases when viewed according to a volume-distance plot: (1) the initiating debris slide, (2) the entrainment phase, and (3) the depositional phase. The rate of debris flow growth is highest during the first phase, nearly linear during the second, and negative during the third phase. When normalized by distance along the flow, the growth rate decays according to a power law E=aXb ( r2≥0.97 ) . This new power law relationship may indicate differences in initiating landslide process and should be leveraged in future runout modeling studies.
Holm, Kris; Scordo, Elisa; Lau, Carie-Ann
Integrated Provincial Flood and Steep Creek Assessments: Connecting Risk Management for Communities Conference
CWRA 2022 National Conference: Valuing Shared Waters , 2022.
@conference{Conference1,
title = {Integrated Provincial Flood and Steep Creek Assessments: Connecting Risk Management for Communities },
author = {Kris Holm and Elisa Scordo and Carie-Ann Lau},
year = {2022},
date = {2022-08-22},
urldate = {2022-08-27},
booktitle = {CWRA 2022 National Conference: Valuing Shared Waters },
abstract = {Mountainous areas of southern British Columbia, Canada, are subject to floods, debris flows and debris floods that can damage property, sever lifelines infrastructure, and cause loss of life. The 2021 consequences of wildfires and atmospheric rivers have kept these issues at the forefront of public concern and highlight the need for coordinated approaches to manage risk. While a de-centralized approach to geohazards management in BC has placed risk management responsibilities with those closest to the need, it has also created knowledge silos and divided responsibilities that are barriers to risk reduction. We have been working with local governments and partners to integrate geohazards management projects across jurisdictional boundaries and organizational responsibilities, where the connection of knowledge, tools, funding, and approaches is creating a stronger path to risk reduction than any single authority may accomplish in isolation. Steps of integrated risk prioritization encompass about one third of BC to date, with data models built to support a provincial knowledge hub. Regional flood and steep creek risk prioritization compares relative contributions of hazard, exposure, and vulnerability to risk, with detailed flood and steep creek assessments in high priority areas followed by risk assessment, policy integration and risk control planning. Current steps include the incorporation of post-wildfire and post-November 2021 flood recovery efforts into risk management planning, and further work to connect private and public sector parties with different responsibilities but shared incentives to manage risk.},
keywords = {},
pubstate = {published},
tppubtype = {conference}
}
Mountainous areas of southern British Columbia, Canada, are subject to floods, debris flows and debris floods that can damage property, sever lifelines infrastructure, and cause loss of life. The 2021 consequences of wildfires and atmospheric rivers have kept these issues at the forefront of public concern and highlight the need for coordinated approaches to manage risk. While a de-centralized approach to geohazards management in BC has placed risk management responsibilities with those closest to the need, it has also created knowledge silos and divided responsibilities that are barriers to risk reduction. We have been working with local governments and partners to integrate geohazards management projects across jurisdictional boundaries and organizational responsibilities, where the connection of knowledge, tools, funding, and approaches is creating a stronger path to risk reduction than any single authority may accomplish in isolation. Steps of integrated risk prioritization encompass about one third of BC to date, with data models built to support a provincial knowledge hub. Regional flood and steep creek risk prioritization compares relative contributions of hazard, exposure, and vulnerability to risk, with detailed flood and steep creek assessments in high priority areas followed by risk assessment, policy integration and risk control planning. Current steps include the incorporation of post-wildfire and post-November 2021 flood recovery efforts into risk management planning, and further work to connect private and public sector parties with different responsibilities but shared incentives to manage risk.
Sharma, Keshab; Bin, Jia; Deng, Lijun
Introduction to a Performance-Based Design Method for Rocking Shallow Foundations in Seismic Zone Conference
GeoCalgary, 2022.
@conference{Conference1,
title = {Introduction to a Performance-Based Design Method for Rocking Shallow Foundations in Seismic Zone},
author = {Keshab Sharma and Jia Bin and Lijun Deng},
year = {2022},
date = {2022-08-20},
urldate = {2022-08-20},
booktitle = {GeoCalgary},
abstract = {This paper proposes a performance-based seismic design (PBSD) methodology for design of rocking shallow foundations for ordinary bridges in cohesive soils. This PBSD considers three performance indicators: maximum drift, residual footing rotation and residual settlement. The empirical equations of re-centering ratio and residual settlement obtained from field testing program of rocking foundation were adopted to check the performance in terms of residual drift and residual settlement. Empirical correlations to obtain the secant stiffness, hysteresis damping ratios, re-centering ratio and residual settlement were obtained from preceding field tests. The shallow foundation of as-built Sanguinetti Bridge, Sonora County, California, was re-designed for assumed cohesive soil sites in British Columbia. It is observed that the foundations of Sanguinetti Bridge can be designed reasonably well using the PBSD while satisfying the performance criteria for 2% maximum drift, residual drift, and residual settlement. The performance of the re-designed bridge was further validated using nonlinear time history analyses. The finite element model was developed in OpenSees platform, validated against the field test results.},
keywords = {},
pubstate = {published},
tppubtype = {conference}
}
This paper proposes a performance-based seismic design (PBSD) methodology for design of rocking shallow foundations for ordinary bridges in cohesive soils. This PBSD considers three performance indicators: maximum drift, residual footing rotation and residual settlement. The empirical equations of re-centering ratio and residual settlement obtained from field testing program of rocking foundation were adopted to check the performance in terms of residual drift and residual settlement. Empirical correlations to obtain the secant stiffness, hysteresis damping ratios, re-centering ratio and residual settlement were obtained from preceding field tests. The shallow foundation of as-built Sanguinetti Bridge, Sonora County, California, was re-designed for assumed cohesive soil sites in British Columbia. It is observed that the foundations of Sanguinetti Bridge can be designed reasonably well using the PBSD while satisfying the performance criteria for 2% maximum drift, residual drift, and residual settlement. The performance of the re-designed bridge was further validated using nonlinear time history analyses. The finite element model was developed in OpenSees platform, validated against the field test results.
Don, Jessica; Shaw, John; Nicolae, Ana; Sorlien, Christopher; Nicholson, Craig; Plesch, Andreas
Late Pleistocene Slip Rate and 3D Geometry of Mid-Channel Blind Thrust, Santa Barbara Channel Implications Earthquake Hazards Journal Article
In: Bulletin of the Seismological Society of America, 2022.
@article{journal1,
title = {Late Pleistocene Slip Rate and 3D Geometry of Mid-Channel Blind Thrust, Santa Barbara Channel Implications Earthquake Hazards},
author = {Jessica Don and John Shaw and Ana Nicolae and Christopher Sorlien and Craig Nicholson and Andreas Plesch},
doi = {10.1785/0120220048},
year = {2022},
date = {2022-08-15},
urldate = {2022-08-15},
journal = {Bulletin of the Seismological Society of America},
abstract = {The Mid‐Channel fault is an active blind thrust overlain by a south‐vergent anticline in the Santa Barbara channel of southern California. We use high‐quality industry seismic reflection data to characterize the 3D geometry of the Mid‐Channel fault, and define its lateral extent and interactions with other structures in the region. We use a detailed chronostratigraphic sequence of nine Pleistocene horizons ranging in age from 120 ka to 1.05 Ma to interpret the geometry and deformational history of the Mid‐Channel anticline and blind thrust. These precisely dated horizons provide unique insights on the Pleistocene activity of the Mid‐Channel fault because of the nearly complete preservation of sediment on the backlimb of the fold. Using a new method of relating structural relief of these horizons to slip on the underlying Mid‐Channel fault, we calculate the faults late Pleistocene slip rate. Results indicate that the structure became active between 790 and 710 ka in the eastern part of the Channel and subsequently propagated west along strike. In the east, where the overlying anticline preserves a complete section of syntectonic growth strata, the Mid‐Channel fault has a dip‐slip rate of 1.8 mm/yr with a range of 1.6–2.1 mm/yr. Based on a map of total displacement, we infer that the maximum dip‐slip rate on the Mid‐Channel fault along strike is 2.1 ± 0.2 mm/yr, suggesting that it may accommodate about one‐third of the observed geodetic contraction across the basin. We explore alternative ways that the fault may extend to depth and interact with surrounding structures, and consider the seismic hazard implications of these scenarios, including estimates of potential earthquake rupture areas, magnitudes, and average recurrence intervals.},
keywords = {},
pubstate = {published},
tppubtype = {article}
}
The Mid‐Channel fault is an active blind thrust overlain by a south‐vergent anticline in the Santa Barbara channel of southern California. We use high‐quality industry seismic reflection data to characterize the 3D geometry of the Mid‐Channel fault, and define its lateral extent and interactions with other structures in the region. We use a detailed chronostratigraphic sequence of nine Pleistocene horizons ranging in age from 120 ka to 1.05 Ma to interpret the geometry and deformational history of the Mid‐Channel anticline and blind thrust. These precisely dated horizons provide unique insights on the Pleistocene activity of the Mid‐Channel fault because of the nearly complete preservation of sediment on the backlimb of the fold. Using a new method of relating structural relief of these horizons to slip on the underlying Mid‐Channel fault, we calculate the faults late Pleistocene slip rate. Results indicate that the structure became active between 790 and 710 ka in the eastern part of the Channel and subsequently propagated west along strike. In the east, where the overlying anticline preserves a complete section of syntectonic growth strata, the Mid‐Channel fault has a dip‐slip rate of 1.8 mm/yr with a range of 1.6–2.1 mm/yr. Based on a map of total displacement, we infer that the maximum dip‐slip rate on the Mid‐Channel fault along strike is 2.1 ± 0.2 mm/yr, suggesting that it may accommodate about one‐third of the observed geodetic contraction across the basin. We explore alternative ways that the fault may extend to depth and interact with surrounding structures, and consider the seismic hazard implications of these scenarios, including estimates of potential earthquake rupture areas, magnitudes, and average recurrence intervals.
Chou, Alan; Brachman, Richard; Rowe, Kerry
Leakage Through a Hole in a Geomembrane Beneath a Fine-Grained tailings Journal Article
In: Canadian Geotechnical Journal, vol. 59, no. 3, pp. 372-383, 2022.
@article{article1,
title = {Leakage Through a Hole in a Geomembrane Beneath a Fine-Grained tailings},
author = {Alan Chou and Richard Brachman and Kerry Rowe},
doi = {10.1139/cgj-2020-0289},
year = {2022},
date = {2022-07-28},
urldate = {2022-07-28},
journal = {Canadian Geotechnical Journal},
volume = {59},
number = {3},
pages = {372-383},
abstract = {Leakage through a 10-mm-diameter hole in a geomembrane beneath fine-grained tailings is examined for a range of pore pressures and effective stresses. Leakage was measured in an experiment with coupled physical and hydraulic conditions to simulate the effective stresses and flow conditions near the hole. The leakage rate was at little as 0.16 L/day with 200 kPa pore pressure (10-30 kPa effective stresses) and increased only to 0.46 L/day with 800 kPa pore pressure (200 kPa effective stress). Seepage analysis of the experiment and local measurements of permeability from small samples extracted after the experiment indicate that the tailings hydraulic conductivity controlling flow was 3–6 x10-9 m/s. Only a subtle decrease in hydraulic conductivity (less than 2 times) near the hole was found. No evidence of seepage induced migration of fines within the tailings was found. Calculations with the parameters deduced from the experiment show that leakage from a tailings storage facilities containing fine-grained tailings can be limited to 1-2 L/ha/day with a geomembrane liner, even when containing up to five 10-mm-diameter holes per hectare, as opposed to an unlined facility with 3 to 4 orders of magnitude more leakage.},
keywords = {},
pubstate = {published},
tppubtype = {article}
}
Leakage through a 10-mm-diameter hole in a geomembrane beneath fine-grained tailings is examined for a range of pore pressures and effective stresses. Leakage was measured in an experiment with coupled physical and hydraulic conditions to simulate the effective stresses and flow conditions near the hole. The leakage rate was at little as 0.16 L/day with 200 kPa pore pressure (10-30 kPa effective stresses) and increased only to 0.46 L/day with 800 kPa pore pressure (200 kPa effective stress). Seepage analysis of the experiment and local measurements of permeability from small samples extracted after the experiment indicate that the tailings hydraulic conductivity controlling flow was 3–6 x10-9 m/s. Only a subtle decrease in hydraulic conductivity (less than 2 times) near the hole was found. No evidence of seepage induced migration of fines within the tailings was found. Calculations with the parameters deduced from the experiment show that leakage from a tailings storage facilities containing fine-grained tailings can be limited to 1-2 L/ha/day with a geomembrane liner, even when containing up to five 10-mm-diameter holes per hectare, as opposed to an unlined facility with 3 to 4 orders of magnitude more leakage.
Feigl, Moritz; Roesky, Benjamin; Herrnegger, Mathew; Schulz, Karsten; Hayashi, Masaki
Learning From Mistakes - Assessing the Performance and Uncertainty in Process-Based Models Journal Article
In: Hydrological Processes, vol. 36, no. 2, 2022.
@article{article1,
title = {Learning From Mistakes - Assessing the Performance and Uncertainty in Process-Based Models},
author = {Moritz Feigl and Benjamin Roesky and Mathew Herrnegger and Karsten Schulz and Masaki Hayashi},
doi = {10.1002/hyp.14515},
year = {2022},
date = {2022-07-27},
urldate = {2022-07-26},
journal = {Hydrological Processes},
volume = {36},
number = {2},
abstract = {Typical applications of process- or physically-based models aim to gain a better process understanding or provide the basis for a decision-making process. To adequately represent the physical system, models should include all essential processes. However, model errors can still occur. Other than large systematic observation errors, simplified, misrepresented, inadequately parametrized or missing processes are potential sources of errors. This study presents a set of methods and a proposed workflow for analyzing errors of process-based models as a basis for relating them to process representations. The evaluated approach consists of three steps: (i) training a machine learning (ML) error-model using the input data of the process-based model and other available variables, (ii) estimation of local explanations (i.e., contributions of each variable to a individual prediction) for each predicted model error using SHapley Additive exPlanations (SHAP) in combination with principal component analysis, (iii) clustering of SHAP values of all predicted errors to derive groups with similar error generation characteristics. By analyzing these groups of different error-variable association, hypotheses on error generation and corresponding processes can be formulated. That can ultimately lead to improvements in process understanding and prediction. The approach is applied to a process-based stream water temperature model HFLUX in a case study for modelling an alpine stream in the Canadian Rocky Mountains. By using available meteorological and hydrological variables as inputs, the applied ML model is able to predict model residuals. Clustering of SHAP values results in three distinct error groups that are mainly related to shading and vegetation emitted longwave radiation. Model errors are rarely random and often contain valuable information. Assessing model error associations is ultimately a way of enhancing trust in implemented processes and of providing information on potential areas of improvement to the model.},
keywords = {},
pubstate = {published},
tppubtype = {article}
}
Typical applications of process- or physically-based models aim to gain a better process understanding or provide the basis for a decision-making process. To adequately represent the physical system, models should include all essential processes. However, model errors can still occur. Other than large systematic observation errors, simplified, misrepresented, inadequately parametrized or missing processes are potential sources of errors. This study presents a set of methods and a proposed workflow for analyzing errors of process-based models as a basis for relating them to process representations. The evaluated approach consists of three steps: (i) training a machine learning (ML) error-model using the input data of the process-based model and other available variables, (ii) estimation of local explanations (i.e., contributions of each variable to a individual prediction) for each predicted model error using SHapley Additive exPlanations (SHAP) in combination with principal component analysis, (iii) clustering of SHAP values of all predicted errors to derive groups with similar error generation characteristics. By analyzing these groups of different error-variable association, hypotheses on error generation and corresponding processes can be formulated. That can ultimately lead to improvements in process understanding and prediction. The approach is applied to a process-based stream water temperature model HFLUX in a case study for modelling an alpine stream in the Canadian Rocky Mountains. By using available meteorological and hydrological variables as inputs, the applied ML model is able to predict model residuals. Clustering of SHAP values results in three distinct error groups that are mainly related to shading and vegetation emitted longwave radiation. Model errors are rarely random and often contain valuable information. Assessing model error associations is ultimately a way of enhancing trust in implemented processes and of providing information on potential areas of improvement to the model.
Acharya, Prabin; Sharma, Keshab
Lessons Learned from the Recovery and Reconstruction Work Following the 2015 Gorkha, Nepal Earthquake Conference
7th Nepalese Scholars' Symposium, 2022.
@conference{Conference1,
title = {Lessons Learned from the Recovery and Reconstruction Work Following the 2015 Gorkha, Nepal Earthquake},
author = {Prabin Acharya and Keshab Sharma},
year = {2022},
date = {2022-07-26},
urldate = {2022-07-25},
booktitle = {7th Nepalese Scholars' Symposium},
abstract = {The 2015 Gorkha, Nepal earthquake was the most devastating disaster faced by the country in the past century. The earthquake affected a huge number of physical infrastructures and jolted the country’s economy. The Nepal government carried out the post-earthquake recovery and reconstruction through a new organization called National Reconstruction Authority (NRA). Nepal had no prior experience with such a level of reconstruction work and had to rely on an inexperienced administration led by the NRA. In the present study, the effectiveness of the recovery process adopted by the NRA has been reviewed with the help of the official reports of the government organizations, government databases, adopted reconstruction laws, published research papers, and field studies in earthquake-affected districts between 2017 and 2019. The study shows that the initial period following a disaster is important to shape the path for any reconstruction. It is also important to have proper recovery plans such that physical and economic recovery could be started immediately following a disaster. A well-resourced, innovative, and result-oriented administration is required which shouldn’t rely on a normal process-oriented bureaucratic system. Apart from these, the implementation strategy should consider community requirements, local demands, and adaptability.},
keywords = {},
pubstate = {published},
tppubtype = {conference}
}
The 2015 Gorkha, Nepal earthquake was the most devastating disaster faced by the country in the past century. The earthquake affected a huge number of physical infrastructures and jolted the country’s economy. The Nepal government carried out the post-earthquake recovery and reconstruction through a new organization called National Reconstruction Authority (NRA). Nepal had no prior experience with such a level of reconstruction work and had to rely on an inexperienced administration led by the NRA. In the present study, the effectiveness of the recovery process adopted by the NRA has been reviewed with the help of the official reports of the government organizations, government databases, adopted reconstruction laws, published research papers, and field studies in earthquake-affected districts between 2017 and 2019. The study shows that the initial period following a disaster is important to shape the path for any reconstruction. It is also important to have proper recovery plans such that physical and economic recovery could be started immediately following a disaster. A well-resourced, innovative, and result-oriented administration is required which shouldn’t rely on a normal process-oriented bureaucratic system. Apart from these, the implementation strategy should consider community requirements, local demands, and adaptability.
Lato, Matthew
Transportation Research Board webinar: Geotechnical data applications and visualization for transportation, 2022.
@workshop{Presentation1,
title = {Lidar Change Detection: Processing, Analysis, and Visualization of LCD Results to Support geotechnical Decisions },
author = {Matthew Lato},
url = {https://onlinepubs.trb.org/onlinepubs/webinars/220623.pdf},
year = {2022},
date = {2022-07-25},
urldate = {2022-07-25},
booktitle = {Transportation Research Board webinar: Geotechnical data applications and visualization for transportation},
abstract = {Processing, analysis, and visualization of LCD results to support geotechnical decisions. Presented as part of the TRB's professional development hour webinar.},
keywords = {},
pubstate = {published},
tppubtype = {workshop}
}
Processing, analysis, and visualization of LCD results to support geotechnical decisions. Presented as part of the TRB's professional development hour webinar.
Zellman, Mark; Lifton, Zach; DuRoss, Christopher; Thackray, Glenn
Lidar Data Reveal New Faults in the Epicentral Region of the 2020 M 6.5 Stanley, Idaho Earthquake Journal Article
In: Seismological Research Letters, 2022.
@article{journal1,
title = {Lidar Data Reveal New Faults in the Epicentral Region of the 2020 M 6.5 Stanley, Idaho Earthquake },
author = {Mark Zellman and Zach Lifton and Christopher DuRoss and Glenn Thackray},
doi = {10.1785/0220220087},
year = {2022},
date = {2022-07-24},
urldate = {2022-07-24},
journal = {Seismological Research Letters},
keywords = {},
pubstate = {published},
tppubtype = {article}
}
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