Surface resistivity measures the electrical resistivity of the subsurface materials, which include soil and groundwater characteristics, from survey stations at the ground surface. Surface resistivity can be used to study lateral changes and vertical cross sections of the natural hydrogeologic setting. Surface resistivity can also be used to study contamination of soil and groundwater and to locate buried objects.
GeoModel, Inc. personnel have conducted numerous surface resistivity surveys and investigations. All surface resistivity surveys are conducted by registered professional geologists. GeoModel, Inc. can travel nationwide or worldwide to conduct a surface resistivity survey.
Surface Resistivity Applications:
Surface Resistivity Method
Application of the surface resistivity method requires that an electrical current be injected into the ground by surface electrodes. The resulting potential field (voltage) is measured at the surface by a voltmeter between electrodes.
The apparent resistivity of the subsurface materials can be calculated by knowing the electrode spacing, geometry of the electrode positions, applied current, and measured voltage. The apparent resistivity values are entered into a computer program that calculates the geoelectric sections or columns for each sounding location, as shown in the images below. Surface resistivity measurements are reported in units of ohm-meters or ohm-feet.
The depth of the resistivity measurement is related to the spacings of the electrodes and may vary depending on the subsurface conditions. The surface resistivity unit has a self-contained transmitter, capable of obtaining data to about 50 to 100 meters (160 to 300 feet), using self-contained, rechargeable batteries.
Surface Resistivity Survey in Africa
GeoModel, Inc. conducted a surface resistivity survey in Warri, Nigeria, Africa for Mosunmolu Ltd. in cooperation with Shell Petroleum Development Company of Nigeria Limited, Warri. The resistivity survey was conducted to map soil layers at a Shell facility.
GeoModel, Inc. used an L&R MiniRes surface resistivity instrument to conduct the survey. A Wenner electrode configuration was used to obtain the apparent resistivity values. The field resistivity data was processed using L&R RESPAC automated inverse modeling software.
Professor Mike Oladapo of the Department of Geophysics of the Federal University of Technology,
Akure, Nigeria, observing the resistivity survey with the MiniRes for Mosunmolu Ltd. at the Shell site
Company Background
GeoModel, Inc. was founded in 1991 as a geophysical services and environmental consulting firm. The company principals have over 50 years of combined experience and have conducted numerous surface resistivity surveys worldwide. All projects are conducted by registered professional geologists.
GeoModel, Inc. conducts surveys in every state.
Contact us to check the availability of a crew in your state.
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Click here for worldwide surveys
e-mail: geomodel@geomodel.com
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