Accession Number : ADA319063

Title :   Installation Restoration Research Program: Assessment of Geophysical Methods for Subsurface Geologic Mapping, Cluster 13, Edgewood Area, Aberdeen Proving Ground, Maryland.

Descriptive Note : Final rept.,

Corporate Author : ARMY ENGINEER WATERWAYS EXPERIMENT STATION VICKSBURG MS GEOTECHNICAL LAB

Personal Author(s) : Butler, Dwain K. ; Sharp, Michael K. ; Sjostrom, Keith J. ; Simms, Janet E. ; Llopis, Jose L.

PDF Url : ADA319063

Report Date : OCT 1996

Pagination or Media Count : 271

Abstract : Seismic refraction, electrical resistivity, and transient electromagnetic surveys were conducted at a portion of Cluster 13, Edgewood Area of Aberdeen Proving Ground, Maryland. Seismic refraction cross sections map the topsoil layer and the water table (saturated zone). The water table elevations from the seismic surveys correlate closely with water table elevations in nearby monitoring wells. Electrical resistivity cross sections reveal a very complicated distribution of sandy and clayey facies in the upper 10 - 15 m of the subsurface. A continuous surficial (topsoil) layer correlates with the surficial layer of the seismic section and nearby boring logs. Below the surficial layer, the complicated facies distribution has resistivities ranging from 25 ohm-m (likely clay) to several thousand ohm-m (dry sands and/or gravels). The complexity and details of the electrical resistivity cross section correlate well with boring and geophysical logs from nearby wells. The transient electromagnetic surveys map the Pleistocene-Cretaceous boundary, the saprolite, and the top of the Precambrian crystalline rocks. Conducting the transient electromagnetic surveys on a grid pattern allows the construction of a three-dimensional representation of subsurface geology (as represented by variations of electrical resistivity). Depths to the Cluster 13 and other areas of the Edgewood Area. Thickness and depth of the saprolitic layer and depth to top of the Precambrian rocks are consistent with generalized geologic cross sections for the Edgewood Area and depths projected from reported depths at the Aberdeen Proving Ground NW boundary using regional dips.

Descriptors :   *ELECTRICAL RESISTANCE, *GEOLOGICAL SURVEYS, *GEOPHYSICS, ELECTROMAGNETIC FIELDS, MARYLAND, ARMY FACILITIES, MOISTURE CONTENT, STRATIGRAPHY, SEISMIC DATA, SEISMIC WAVES, REFRACTION, ENVIRONMENTAL MANAGEMENT, SOIL CHEMISTRY, INSTALLATION RESTORATION, TOPOGRAPHIC MAPS, SOIL CLASSIFICATION, WATER TABLE, SOIL SURVEYS, HYDROGEOLOGY.

Subject Categories : Geology, Geochemistry and Mineralogy
      Soil Mechanics

Distribution Statement : APPROVED FOR PUBLIC RELEASE