Accession Number : ADA189626

Title :   Military Hydrology. Report 15. The Seismic Refraction Compression-Shear Wave Velocity Ratio as an Indicator of Shallow Water Tables. A Field Test.

Descriptive Note : Miscellaneous paper. Aug 85-Jan 86,

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

Personal Author(s) : Schuyler-Rossie, Christine

PDF Url : ADA189626

Report Date : Nov 1987

Pagination or Media Count : 48

Abstract : To test the assumption that the velocity of shear waves increases much less than the velocity of compressional waves at a water table, a seismic refraction survey was performed over a shallow water table in alluvial sediment. Using a sledge hammer and a partially buried steel cylinder as a source, a maximum shot-to-receiver distance of 330 ft and depth of investigation of 60 ft were achieved. The ratio of V(sub p) to V(sub s) (compressional/shear wave velocity) at the water table was found to be 2.48. In the four nonsaturated layers above the water table, V(sub p)/V(sub s) ratios ranged form 1.54 to 1.55. As predicted by the theoretical models considered, shear wave velocity did not increase in compressional velocity at each refractor. While results indicate that the comparison of S- and P- wave velocity profiles is a promising technique for water table detection, more research is necessary to define the reliability and limits of the method. Keywords: Compressional seismic waves; Ground water; Military hydrology.

Descriptors :   *HYDROLOGY, *MILITARY ENGINEERING, *SEISMIC WAVES, ALLUVIUM, BURIED OBJECTS, CYLINDRICAL BODIES, DETECTION, ELASTIC WAVES, FIELD TESTS, GROUND WATER, MODELS, PROFILES, REFRACTION, RELIABILITY, SECONDARY WAVES, SEDIMENTS, SHALLOW DEPTH, SHALLOW WATER, SHEAR PROPERTIES, STEEL, SURVEYS, THEORY, VELOCITY, WATER TABLE, WAVES, GEOPHYSICS

Subject Categories : Civil Engineering
      Hydrology, Limnology and Potamology

Distribution Statement : APPROVED FOR PUBLIC RELEASE