Geo Electrical

The geo-electrical family of geophysical methods includes electrical resistivity, induced polarization, and spontaneous potential. Electrical resistivity is a robust method that relies on measured contrasts in the ability of subsurface materials to conduct electrical current. Induced Polarization (IP) measures the chargeability of subsurface materials and can be collected along with electrical resistivity data. Spontaneous Potential (SP), also known as self-potential, measures the voltage of natural earth electrical potential occurring on the ground surface. These methods often complement one another and may be measured from the surface, in a borehole, or by waterborne instruments for marine applications. Geo-electrical methods may also be combined with other geophysical methods to allow us to leverage synergies.

Geo Electrical Methods

Gehrig’s investment in geo-electrical equipment, data processing software, and research and development allows us to offer our clients the best possible results from 1-D, 2-D, and 3-D geo-electrical studies.

Typical geo-electrical investigations include:

  • Dam and levee seepage studies
  • Karst feature mapping
  • Tests for grounding and corrosion
  • Site stratigraphy and soil mapping
  • Groundwater exploration
  • Mineral and aggregate exploration
  • Landfill delineation
  • Contaminant plume mapping
  • Salt water intrusion
  • Depth to bedrock
  • Identification of Areas of Geological Concern (AGCs)
  • Preferential pathway mapping

Example graphics from previous geo-electrical investigations are included below.

  • 2-D Electrical Resistivity and Induced Polarization Profiles for Groundwater Exploration
  • 3-D Electrical Resistivity and Induced Polarization Data Illustrating a Karst Feature