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Environmental & Engineering Geophysics
“Looking through a dark glass dimly.”
Insights into groundwater, runoff and the impact of humankind on the environment.
© John F. HermanceAugust 31, 2004
Who uses near surface geophysics?
Archaeology
IsraelPre Columbian
America
© John F. HermanceAugust 31, 2004
Runoff mechanisms
Runoff mechanisms
Hydrology© John F. Hermance
August 31, 2004
Subsurface features
Subsurface features
Hydrology© John F. Hermance
August 31, 2004
The geophysicist’s mission:We begin with a blank slate.
© John F. HermanceAugust 31, 2004
Using non-invasive methods, and what other information is available we try to answer . . .
© John F. HermanceAugust 31, 2004
© John F. Hermance
August 31, 2004
Using non-invasive methods, and what other information is available we try to answer . . .
What’s in the subsurface?
© John F. HermanceAugust 31, 2004
(Some of the questions.)
What’s in the subsurface?
© John F. HermanceAugust 31, 2004
(Some of the questions.)
What’s in the subsurface?
© John F. HermanceAugust 31, 2004
(Some of the questions.)
What’s in the subsurface?
© John F. HermanceAugust 31, 2004
(Some of the questions.)
© John F. Hermance
August 31, 2004
(Some of the questions.)
© John F. HermanceAugust 31, 2004
Example of a Non-Invasive Geophysical Technique:Ground Penetrating Radar (GPR)
Principle of GPR
© John F. HermanceAugust 31, 2004
Applying our “composite” moveout correction to
trace cross-correlation functions (VTrial = 0.074 m/ns)
(But we also need Vrefractor = 0.122 m/ns) Plot of GPR signals recorded along a profile .
© John F. HermanceAugust 31, 2004
Delineating a Stratigraphic Horizon:The “geologic” interpretation of ground penetrating radar (GPR) data.
© John F. HermanceAugust 31, 2004
Geophysics that has been done to characterize site:
Seismic refraction, DC resistivity, EM, GPR and gravity.
[Seismic interpretation from Jeff Sullivan (personal communication.).]
Delineating several stratigraphic horizons & bedrock
© John F. HermanceAugust 31, 2004
What about infrastructure?© John F. Hermance
August 31, 2004
Application of the Magnetic Method to Assess “Missing” Items at a Florist’s
Shop.
© John F. HermanceAugust 31, 2004
© John F. Hermance
August 31, 2004
An alternative way to present GPR data:Time Slice “Plan” or “3D” View Formats.
© John F. HermanceAugust 4, 2003
Field Site: Long IslandNorth
Time Slice:3D View
Field Site: Long Island.Objective: Detect leaching pits.
© John F. HermanceAugust 31, 2004
Time Slice:3D View
Interpretation?
© John F. HermanceAugust 31, 2004
Time Slice:Plan View(w / interpretation)
© John F. HermanceAugust 31, 2004
Application of the Magnetic Method to Delineate a Buried (Lost) “Vault” at a Fall
River Mill Site.
© John F. HermanceAugust 31, 2004
© John F. HermanceAugust 31, 2004
Environmental & Engineering Geophysics
End of Presentation
“Looking through a dark glass dimly.”
© John F. HermanceAugust 31, 2004
