Innovation and Partnerships Office

Hybrid MRS-TEM for Mapping Shallow Aquifers 2014-057

APPLICATIONS OF TECHNOLOGY:

Locating and characterizing

  • Groundwater
  • Subsurface hydrocarbon reservoirs

ADVANTAGES:

  • More accurate aquifer assessment than conventional exploration systems
  • Single instrumentation package

ABSTRACT: 

Frank Morrison, Erika Gasperikova and Alessandro Ratti of Berkeley Lab have developed a lightweight system for measuring depth and quantity of groundwater, salinity of groundwater, porosity of soil, and presence of clay using magnetic resonance sounding (MRS) and transient electromagnetic (TEM) method combined in a common instrumentation package. The technology promises to deliver more accurate data than MRS or resistivity mapping alone, therefore avoiding costly, unproductive drilling.

Conventional electrical and electromagnetic exploration systems can determine the distribution of electrical resistivity in the subsurface. However, the resistivity of a given region of the subsurface depends on many factors, such as porosity, pore fluid salinity, fluid saturation, and clay content, and using resistivity measurements alone for the identification of a good freshwater aquifer is highly problematic. MRS can offer direct estimations of the depth, thickness and water content of aquifers yet cannot indicate salinity of the aquifer and, therefore, water quality.

Conducting MRS and resistivity mapping together, and acquiring these complementary data, typically requires two different sets of instrumentation. By developing a common instrumentation package combining MRS and ground resistivity measurements, the Berkeley Lab researchers have overcome an obstacle to accessing groundwater resources that meet the water needs of developing countries and regions affected by drought, where water is essential for crop irrigation.

DEVELOPMENT STAGE: A prototype of the dual MRS-TEM system (BWD) can detect and characterize aquifers up to 10 meters deep. The current development is aimed at a rugged portable hardware package and interpretation software that can be shown to identify potable water aquifers at a variety of field sites where the water content, water table and electrical resistivity are known.

STATUS: Patent pending. Available for licensing or collaborative research.