摘要
地震定位是地震学中最基本的问题之一,现阶段大部分采用基于走时的方法。单纯形定位方法作为一种直接搜索类的方法,在新疆测震台网日常地震目录产出中发挥了重要作用。本文采用数值模拟的方法,利用新疆测震台网现有布局,结合"3400"走时表,分析单纯形定位方法在新疆测震台网的测定精度。研究表明,对于新疆测震台网网内浅源地震,单纯形定位方法能够得出较为精确的震中位置,而得出的网外地震震中位置存在一定偏差;初至折射波对震源深度有一定的控制能力,速度模型的准确性对震源深度和发震时刻的测定影响较大。
Seismic location is one of the most basic issues in seismology. Currently, most of earthquake location used a time-based approach. However, the simplex location method, as a direct search method, plays an important role in the daily earthquake catalog of the Xinjiang Digital Seismic Network. This paper applies numerical simulation methods, using the Xinjiang Digital Seismic Network and combing the "3400" travel timetable, and analyzes the measurement accuracy of the simplex location method in the Xinjiang Digital Seismic Network. The results show that for the shallow earthquakes in the Xinjiang Digital Seismic Network, the simplex location method can get a high-accurate epicenter location, However, there exists a certain deviation in outside the seismic network.The first arrival refracted wave has a certain ability to control the depth of the epicenter. The accuracy of the velocity model has a great influence on the depth of the epicenter and the determination of the time of earthquake occurrence.
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