General Method | Specifc method | Use in study (and depth of exploration) |
Type of interpretation (and status) |
Limitations | Advantages |
ELECTRICAL | DC Resistivity | Map complex plumes, complex stratigraphy | Quantitative (production) | Slow; electrical, cultural interference; need larger areas for deep work | Detailed results |
Terrain Conductivity | Map simple plumes and stratigraphy | ||||
EM 31 | (Shallow) | Qualitative (production) quantitative (research) |
Electrical, cultural interference | Fast; simple to use | |
EM 34-3 | (Moderate) | Qualitative (production) quantitative (research) |
Electrical, cultural interference | Fast; simple to use | |
Time-domain EM 37W | Map plumes and stratigraphy | Qualitative (research) | Complex to use | Small surface area for deep penetration | |
Terrain resistivity | Map simple plumes and stratigraphy | ||||
Very low frequency (VLF) EM 16R | (Moderate) | Qualitative (production) quantitative (research) |
Electical, cultural interference | Fast; simple to use | |
Ground Penetrating Radar | Map water table and stratigraphy (shallow) | Qualitative (research) | Complex to use | Very fast | |
Complex resistivity | Map non-conductive plumes (shallow) | Qualitative (research) | Complex to use; slow; must have clay present | Can map non-conductive contaminant | |
SEISMIC | Land refraction | Map depth to water, depth to rock (shallow or deep) | Quantitative (production) | Cultural noise interference; may need explosives; need larger areas for deep work | Detailed results |
Land reflection | Depth to rock (moderate to deep) | Quantitative (research) | Cultural noise interference; may need explosives | Small areas for deep work | |
Marine reflection (single channel) | Detailed stratigraphy, depth to rock (shallow to moderate) | Quantitative (research) qualitative (research) |
Need water | Very fast |
A good reference describing the theory and practice is:
Ward, S. H. (editor), Geotechnical and Environmental Geophysics,
Investigations in Geophysics series, no. 5, v. I-III:
Tulsa, Oklahoma, Society of Exploration Geophysicists, 1032 p., 1990.
Last updated on August 6, 1998 by William P. Clement |