ClearView Geophysics Inc. offers geophysical consulting and surveys as part of your geotechnical investigations.
Geophysical surveys are routinely used for geotechnical investigations. Various methods and instruments are used for locating and describing subsurface features and structures that will impact construction designs. Geophysical techniques can be used for:
The geophysical techniques that can be used are custom designed for the particular application. For example, depth to bedrock surveys take into account the site conditions, accuracy required and project scale. Seismic refraction is recommended in cases where the overburden velocity increases with depth, anticipated depths are less than 60 metres, and the site is relativley "quiet". Resistivity imaging and EM surveys are recommended where conditions for seismic refraction are not ideal. GPR can be used if the overburden is mostly sandy (resistive) and the overburden/bedrock interface is not too deep - typically less than 20 metres. Gravity surveys can be used to detect buried valleys and bedrock escarpments.
Available borehole logs, well logs and test pit data are also used to cross-check and calibrate the results for best precision.