|
Geophysical Method for Subsurface Characterization
Electrical Imaging (EI) is a geophysical method that provides a two- or three- dimensional
resistivity image of the subsurface. EI can provide information about distinct subsurface
boundaries and conditions that other geophysical methods cannot.
|
Applications:
- Map top of bedrock
- Identify potential sinkhole, void and cavern locations
- Map the lateral and vertical limits of waste pits and landfills.
- Identify the location of preferential groundwater flow paths in sand and gravel
channels
- Identify bedrock fractures
|
ARM utilizes an automatic multi-electrode switching system, which passes an electrical
current along multiple paths at various depths and measures the resulting associated
voltages between electrodes. Apparent resistivity measurements are recorded from
all possible combinations between two electrodes. Processing of the data using resistivity
inversion software provides a subsurface model with a more unique or quantitative
interpretation of the data than possible in the past.
New advances in EI methods have included three-dimensional surveys and cross-borehole
surveys which make this technique even more successful for subsurface characterization.
In areas where very complex three-dimensional subsurface features are present, three-dimensional
survey data collection techniques and data inversion software can provide more accurate and useful subsurface models.

|