Thank you for your question regarding ground water exploration using soil resistivity measurements. It is our pleasure to help.
It is quite common to conduct groundwater explorations using various soil resistivity measurement and imaging techniques. Most often, these groundwater explorations utilize a variety of 2D resistivity imaging techniques, versus the 1D type often used when conducting soil testing for electrical safety requirements.
Conducting deep groundwater surveys is typically done by combining three (3) different electrode array methods: dipole-dipole, Schlumberger and pole-dipole. Through a combination of these three methods in one survey, it is possible to get both a high resolution and a deep penetration of the earth. It has been reported that groundwater has been successfully found as deep as 375 meters (1,230 feet) using these techniques. You will have to have some very specialized software to invert all three data sets from the various electrode arrays together in to a single profile. Similar techniques have been used to locate water in sedimentary aquifers and in bearing fracture zones in bedrock.
E&S Grounding Solutions recommends and uses soil resistivity meters from Advanced Geosciences, Inc. (AGI) in Austin, Texas. This company has several case files available online for you to review and information regarding both the meters they manufacture and the software products that can be used to find groundwater using soil resistivity measurements.
If you should have any further questions, please do not hesitate to contact us again in the future.
The Engineering Team at E&S Grounding Solutions
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