Geophysics

Geophysical studies for geological mapping related to water resources typically use seismic refraction, seismic reflection, electromagnetic induction (EM), or electrical resistivity methods. The main goal of the program is to assist with geologic mapping of potential aquifers by providing information between and beyond existing well data. Geophysical studies are also used to locate buried artifacts and/or waste material. For example, they can be used to find buried drums or other metal at hazardous waste sites. They can also help in archeological studies. Typically, EM and magnetic methods are used for these applications.

Geophysical mapping is done in conjunction with geological mapping and test drilling. Program staff members work cooperatively with the Ground Water Technical Analysis Program, the Observation Well Program, and the Ground Water Mapping Program to support DNR mapping efforts. Program staff also conduct geophysical field studies for cooperative projects with other government agencies, most typically with the Minnesota Geological Survey (MGS) and the U.S. Geological Survey-Water Resources Division (USGS-WRD).

Geophysics Data

Geophysics data is available on request.

The map shows a plot of seismic refraction and resistivity imaging data collected by the County Geologic Atlas program.

  • The seismic refraction lines usually show the ground surface, the interpreted top of the water table and first bedrock unit.
  • The resistivity imaging lines show interpreted resistivity values along each line versus depth.
map of minnesota showing a plot of seismic refraction and resistivity imaging data

    Reports

    Groundwater Exploration Using Geophysical Methods

    Resistivity Imaging

    Questions