Borehole geophysics utilizes boreholes or wells to make geophysical measurements. Compared to geophysical measurements made on the ground surface, they have better resolution in the depth dimension. Borehole geophysics can be performed in a single borehole as in the borehole logging, or in two or more boreholes for cross-hole resistivity, GPR and seismic measurements, etc. While the borehole logging can provide detailed information in the immediate area of the boreholes, cross-hole measurements and sometimes with additional ground surface sensors can provide more information in a much broader area, especially between or among the boreholes.

In the borehole logging, geophysical sensors or probes are lowered down to the borehole to collect data that are generally presented graphically along the depth dimension. Enviroprobe provides the following logging services: gamma, caliper, temperature, resistivity, single-point resistance, spontaneous potential, electromagnetic induction, optical televiewer, acoustic televiewer and flow meter, etc.

The applications of the borehole logging include:

--Groundwater quality investigation
--Lithology and soil strata characterization
--Water-bearing zone locating
--Bedrock fracture delineation

Enviroprobe also provides resistivity tomography services utilizing ground and downhole electrodes. The typical applications include underground void locating, bedrock fracture/fault locating and underground water monitoring, etc.

Resistivity tomography utilizing both ground and downhole electrodes