Three-Dimensional Wave Propagation Effects in Teleseismic Body Waves

本研究的目的是研究和模拟南加州地震活跃区宽带TERRAscope台站接收到的地震体波的异常粒子运动和尾波。这些影响被认为是由于台站附近的横向非均质性，包括断层。了解横向速度非均质性的影响对于利用简单的1-D地球模型评估波形建模的误差和确定岩石圈内的波散射机制至关重要。异常观测本身可能有助于推断非均质性的类型和大小。将调查所有可用TERRAscope站点的数据，以推断横向非均质性。除了地质构造导致的速度非均质性外，地形的影响也将被研究，以确定地形是否在P波尾波的形成和P波粒子运动的解释中起主要作用。这项研究是国家减少地震危害计划的一个组成部分。

This research is to investigate and model anomalous particle motions and coda of seismic body waves received at broad-band TERRAscope stations in the active seismic region of southern California. These effects are believed to be due to lateral heterogeneity, including faults, near the stations. Understanding the effects of lateral velocity heterogeneity is essential for evaluating errors in waveform modeling using simple 1-D earth models and determining wave scattering mechanisms within the lithosphere. The anomalous observations themselves may be useful in inferring constraints on the type and magnitude of heterogeneity. Data from all available TERRAscope stations will be investigated for inference of lateral heterogeneity. In addition to velocity heterogeneity due to geologic structure, effects of topography will be investigated to determine if topography plays a major role in formation of P wave coda and the interpretation of the P waveform particle motions. This research is a component of the National Earthquake Hazard Reduction Program.