Integrated Modeling Hydrogeological-Thermal-Consolidation Processes in Accretionary Complexes--with Emphasis on the Oregon-Washington-Vancouver Margin

点击翻译按钮获取中文摘要

Accretionary prisms form at convergent margins where one lithospheric plate is underthrusting an adjacent lithospheric plate and sediments are being scraped off the downgoing plate. These offscraped sediments form a large pile (accretionary prism) in front of the overriding plate with thickness of 10 to 20 kms. This thick wedge of sediments consolidates by dewatering; the details of this consolidation process are poorly understood but are known to involve heat and fluid transport within the prism as well as deformation of the sediments and rock that form the prism. Professor Wang will generate a computer finite element model of the accretionary prism on the Oregon-Washington margin integrating hydrogeological, thermal, and consolidation processes. A finite element model created previously under OCE86-05986 did not integrate hydrogeological and thermal aspects in that computations for hydrological, thermal, and deformational processes were performed sequentially for any given time step. Wang proposes now to fully couple the computations in that all relevant variables will be solved for simultaneously - closer to the natural process. He proposes to use the wealth of thermal, seismic, physical properties, and fluid flow measurements available from the Oregon margin as boundary conditions on his models.