Accession Number : ADA320396

Title :   Slope Failure, Tectonics, and Gas and Fluid Expulsion on the Southern Cascadia Continental Shelf and Slope: Effects on Seafloor Geomorphology.

Descriptive Note : Interim rept. 1 Jan-14 Oct 96,

Corporate Author : MONTEREY BAY AQUARIUM RESEARCH INST PACIFIC GROVE CA

Personal Author(s) : Orange, Daniel L.

PDF Url : ADA320396

Report Date : 14 OCT 1996

Pagination or Media Count : 7

Abstract : The objective of this project is to evaluate the role of fluid flow, overpressuring, and gas migration in the creation of failure features on the seafloor of a tectonically active continental margin. This project addresses questions about the lateral and vertical extent of detectable gas and gas-related structures in the subsurface, the regional distribution of failure features, the locations of overpressured fluids in the subsurface, and how the structural geology of this region affects the locations of gas and fluid migration pathways and expulsion sites. We pursue answers to these questions using a combination of theoretical and observational analyses. Observations and hypotheses based upon remote sensing techniques (industry-quality multichannel seismic, high resolution multichannel seismic, high resolution single channel seismic, acoustic reflectivity, high resolution sidescan, high resolution bathymetry) will be ground-truthed with direct observation and sampling via use of a remote operated vehicle (ROV). These observations will become the basis for modeling the relationship between gas-charged fluids and slope failure. Fulfillment of these objectives will allow us to obtain a better understanding of the dynamic processes occurring on the southern Cascadia continental shelf and slope, and ultimately help address how sediment is transported from the shelf to upper slope, and from the upper slope to abyssal depths.

Descriptors :   *CONTINENTAL SLOPES, *GEOMORPHOLOGY, OVERPRESSURE, HIGH RESOLUTION, GAS DYNAMICS, CONTINENTAL SHELVES, BATHYMETRY, SEDIMENT TRANSPORT, SEISMIC DATA, MARINE GEOLOGY, SEISMIC REFLECTION, REMOTE DETECTORS, STRUCTURAL GEOLOGY, SEAFLOOR SPREADING, TECTONICS, ACOUSTIC REFLECTION, EXPULSION, HYDROGEOLOGY.

Subject Categories : Physical and Dynamic Oceanography
      Geology, Geochemistry and Mineralogy
      Seismology

Distribution Statement : APPROVED FOR PUBLIC RELEASE