Investigation of Seismic Anisotropy above a Wadati-Benioff Zone

本研究主要是分析上层介质中的剪切波分裂 地幔在南美洲西部的两个地区，火山区 哥伦比亚西部布卡拉曼加西南部， 位于秘鲁中部的火山区。 这项分析将涉及数据 从当地和东部地震，并将用于 与在布卡拉曼加获得的结果相比， 归因于上地幔中的楔形各向异性体积 就在Wadati-Benioff区上方，特别是在一个 火山与非火山环境的对比 结果将影响到 俯冲板块引起的地幔变形模型 从而对地震发生的机制进行了研究， 世界上最活跃的地震区 这项研究是一个 国家地震减灾计划的一部分。

This research is to analyze shear-wave splitting in the upper mantle in two areas in western South America, a volcanic area southwest of Bucaramanga in western Colombia, and a large non- volcanic area in central Peru. This analysis will involve data from both local and teleseismic earthquakes and will be used to compare to results obtained at Bucaramanga where splitting was ascribed to a wedge-shaped anisotropic volume in the upper mantle immediately above the Wadati-Benioff zone, especially in a volcanic versus a non-volcanic setting. The results will bear on models of deformation of the mantle due to the subducting slab and thereby on the mechanism of earthquake generation in one of the world's most active seismic areas. This research is a component of the National Earthquake Hazard Reduction Program.