2D and 3D Seismic Imaging of Seamount Collision and Subduction Across the Central Chilean Margin

该项目将分析在智利中部胡安费尔南德斯地震脊俯冲的边缘收集的一组海底地震仪地震数据。速度结构将沿着与海岸垂直的两条横断面和位于瓦尔帕莱索盆地下可能埋藏的海山上方的网格确定。这些数据将用于(1)测试海山是否存在，如果存在，它是否充当了1985年地震的焦点的“隆起”；(2)确定吸积楔和岩石圈的三维形状和速度结构，以约束俯冲板块的沉积物孔隙度和弹性。

This project will analyze a set of OBH seismic data collected off the margin of central Chile where the aseismic Juan Fernandez Ridge is being subducted. Velocity structure will be determined along two transects normal to the coast and in a grid sited over a possible buried seamount under the Valparaiso Basin. The data will be used to (1) test whether there is a seamount and if so whether it acts as an "asperity" which may have served as a focus for the 1985 earthquake and (2) determine the 3D shape and velocity structure of the accretionary wedge and lithosphere to constrain sediment porosity and elasticity of the subducting plate.