Geotechnical Applications of Borehole Geophysics

Miniaturization of instrumentation has opened up the use of borehole geophysical techniques to geotechnical consultants, but most are not yet acquainted with the capabilities of the procedures. Borehole geophysics has been used widely in studies of nuclear power plant sites, waste disposal problems, and local and regional geohydrological relationships. Most investigations have been oriented toward stratigraphic correlation and assessment of lithologies. However, there is a wealth of semi-quantitative or quantitative data available which is often overlooked. Because of the environments in which the geotechnical specialist works, exploratory borings are most frequently cased, and the radiation group of geophysical devices must be used. In properly engineering borings and with appropriate calibration, these devices can evaluate moisture content, density, and porosity.