Understanding earth processes from afar
BGC is an industry leader in using remote sensing technologies to observe, interpret, and understand the physical environment, particularly as it applies to mapping differential change. Our remote sensing team has extensive experience in the application of terrestrial, aerial, and satellite-based technologies on the pipeline, transportation, mining, energy, and communities sector projects, and integration of these technologies into monitoring and asset management programs of varying scales. These techniques can be applied to monitoring slope movement, dams, and other structures, mapping the progress of earthworks, and understanding the impacts of natural hazards such as flooding and forest fires. Selecting the most appropriate remote sensing technology for a particular application depends on many factors including technical, environmental, logistical, and financial considerations. BGC’s team helps to ensure clients are selecting the best option(s) for their project needs.
Monitoring of slope movement has traditionally been limited to costly sporadic borehole mapping and instrumentation data, discrete surface measurements and observations, and interpolated geophysical data. With recent advancements in remote sensing data collection and analysis algorithms, we have been able to understand the mapping of slope processes with a greater degree of accuracy and confidence. BGC is an industry leader in the application of 4D change detection methods to observe, interpret, and understand the physical environment, particularly as it applies to mapping differential change. Change detection and InSAR results delivered through Cambio™ allow clients to interact with the data and visualize results alongside asset, inspection, and instrumentation info.
Lidar is a surveying technology that measures distance by illuminating a target with laser light and is typically used to make high-resolution maps. Airborne Lidar Scanning (ALS) is a laser scanner that creates a 3D topographic model of the landscape while attached to a plane, helicopter, or uncrewed aerial vehicle (UAV) during flight. The technology collects data over spatially extensive regions requiring limited ground access to sites and is currently the most detailed and accurate method of creating digital elevation models. ALS data are typically used to support regional scale geohazard mapping, monitoring, and assessment.
Terrestrial Lidar Scanning (TLS) data collection requires ground access to scan setup locations but does not require onsite access to the terrain. The TLS data can be used to identify small-scale features not typically possible in ALS data and can create realistic-looking 3D models in a relatively short time when compared to other technologies. Terrestrial Laser Scanning equipment can be rapidly deployed, and the data integrated into differential change models within hours of collection. TLS data can be used to support high-frequency monitoring of specific slopes or structures.
Photogrammetry is the science of measuring the distance between two points on a photo image. This system may be used to determine the exact position of surface points as well as the motion pathways of reference points located on a moving object. Most commonly, a technique called Structure from Motion (SfM) is used to generate 3-dimensional (3D) models from overlapping photographs.
Photogrammetry can provide excellent 3D models and imagery for various engineering geology applications. BGC has pioneered methodologies for helicopter-based photogrammetry data collection and differential change of rock slopes along transportation corridors. UAV-based photogrammetry is used to support inspections for pipeline geohazard assessments and to monitor construction progress on geohazard mitigation and dam construction projects.
Radar interferometry methods are used to measure changes and displacements of natural and constructed slopes. Terrestrial methods can provide near-real-time measurements of slopes of concern. BGC are experts in the analysis and interpretation of data from industry-leading data providers and commonly used terrestrial hardware systems.
The field of space-based earth observation is concerned with the monitoring of natural or man-made environments using data captured by Earth-orbiting satellites. The rapid increase in earth-observing satellites provides unprecedented access to data for observing the land, cryosphere, hydrosphere, and atmosphere and how these systems change over time. The global coverage makes earth observation data particularly valuable in data-sparse regions where conventional sources of data (including airborne or in-situ observations) may be unavailable. These data, once processed and analysed, can serve a wide range of applications, including the detection and monitoring of geotechnical and hydrotechnical hazards, monitoring natural hazards (such as flooding and wildfires) as well as post-disaster assessments and management.