Subsurface exploration in alluvial terrain by surface geophysical methods. Final report

Technical Report · Thu Dec 01 04:00:00 EST 1977

OSTI ID:7051766

Murphy, W L

Field tests were conducted at several sites in Louisiana to determine the effectiveness of two geophysical tools for detecting and locating subsurface geological features in alluvial terrain. The hammer seismic refraction technique, using a hammer source and portable seismograph, and the surface electrical resistivity method, using a D.C.-powered resistivity meter and current source, were investigated. Seismic refraction lines and resistivity soundings and profiles were run concurrently at each site. Boring control was used where available to aid in interpretation of the geophysical data. The resistivity profiling (fixed electrode spacing) technique was the most successful of the three methods, detecting or locating the targeted geologic feature at three of the four sites tested. The resistivity sounding (expanding electrode spacing) technique delineated shallow features but was ineffective at depth. The hammer seismic technique also achieved only limited success at depth, attributed primarily to attentuation of the seismic signals by loose near-surface materials. Surveys were precluded at one site by the presence of certain man-made features that interfered with the collection of usable data.

• Research Organization: Army Engineer Waterways Experiment Station, Vicksburg, MS (USA)
• OSTI ID: 7051766
• Report Number(s): AD-A-049125; WES-MP-S-77-24
• Country of Publication: United States
• Language: English

Related Subjects

58 GEOSCIENCES
580203* -- Geophysics-- Geophysical Survey Methods-- (1980-1989)
ALLUVIAL DEPOSITS
ELECTRIC CONDUCTIVITY
ELECTRICAL PROPERTIES
ELECTRICAL SURVEYS
GEOLOGIC DEPOSITS
GEOPHYSICAL SURVEYS
LOUISIANA
MEASURING INSTRUMENTS
NORTH AMERICA
PERFORMANCE TESTING
PHYSICAL PROPERTIES
REFRACTION
SEISMIC DETECTORS
SEISMIC SURVEYS
SEISMOGRAPHS
SOUTHWEST REGION
TESTING
USA