Accession Number : ADA323133

Title :   Continental Borderlands Shear Structure from Seafloor Compliance Measurements.

Descriptive Note : Final rept.,

Corporate Author : SCRIPPS INSTITUTION OF OCEANOGRAPHY LA JOLLA CA MARINE PHYSICAL LAB

Personal Author(s) : Hildebrand, John A.

PDF Url : ADA323133

Report Date : NOV 1996

Pagination or Media Count : 8

Abstract : Shear properties are poorly known for shallow water sediments because of the difficulty of making direct measurements. Deformation from low frequency waves provides information about deep structure and from high frequency waves provides information about shallow structure. Seismic reflection profiles of several major faults in this area have revealed that they are actively deforming young sediments. As the sediments are uplifted or compressed, their pore-water content may be significantly altered; at several locations along these faults, springs have been observed where pore-water is being expelled at the seafloor, precipitating mineral deposits and supporting colonies of tubeworms. The change in shear strength associated with pore-water loss has been recognized as an important parameter in controlling fault mechanics. This project studied the elastic structure of shallow water sediments using measurements of seafloor compliance. One approach for determining shear properties is to measure seafloor deformations resulting from the loading of ocean waves, this is the approach of the compliance technique.

Descriptors :   *SHEAR PROPERTIES, *SEISMIC REFLECTION, *OCEAN BOTTOM SOILS, OCEAN WAVES, DEFORMATION, SHALLOW WATER, GEOPHYSICS, UNDERWATER ACOUSTICS, OCEAN BOTTOM.

Subject Categories : Geology, Geochemistry and Mineralogy
      Seismology

Distribution Statement : APPROVED FOR PUBLIC RELEASE