地震发震断层的形态、尺度、破裂方向性与破裂速度这些震源运动学特征参数在地震学研究中是十分重要的。对于中小地震，传统的点源机制解只能给出两个等效的节平面，无法确定其他参数。高阶地震矩方法是近年来发震起来的一种研究震源运动学特征的方法，单个点源的高阶矩即可有效模拟有限尺度断层产生的地震波形。本项目中拟建立了一种简单、快速、有效地利用高阶地震矩张量确定震源参数（包括断层几何形态、断层尺度、破裂方向以及破裂速度等）的新方法。基于均匀层状介质模型，使用广义反射透射系数矩阵和离散波数方法计算高阶地震矩张量理论地震图，对于中等强度地震（3.5<M<5.5）采用长周期波形直接反演，对于小震（M<3.5）,先进行波形振幅校正再反演，以减小三维速度结构的影响。利用该方法确定2014年2月14日新疆于田地震及2014年8月3日云南鲁甸地震的主要余震的震源参数，加深对震源特性与发震构造的认识。

The source parameters of earthquake, for example, the geometry, length, width, rupture directivity and rupture velocity of earthquake fault, are significant in seismology research. For small and moderate earthquakes, traditional point seismic moment tensor only determines two nodal planes and doesn’t give the other source parameters. Higher moment tensor method is a new method to study the kinematic characteristics of earthquake source in recent years. Only a point source model could simulate waveforms caused by a finite-fault model. In this project, we intend to establish a simple, rapid, efficient method to determine source parameters (including fault geometry, fault rupture directivity and rupture velocity, etc.) using higher moment tensor. Based on the homogeneous layered crust model, we use the generalized reflection transmission coefficient matrix and discrete wavenumber method to simulate the synthetic seismograms of higher moment tensor. For a moderate earthquake (3.5<M<5.5), the source parameters would be investigated using long period waveforms. For small earthquake (M<3.5), the amplitudes of short period waveforms are adjusted by the Amplitude Amplification Factor firstly and then would be used to determine the source parameters and thus the effect of 3-D crust model would be avoided. We investigate the source parameters of the aftershocks of February 14, 2014 Xinjiang Yutian earthquake and the August 3, 2014 Yunnan Ludian earthquake using the higher moment tensor method, in order to understand the source characteristics and seismic tectonic structures deeply.