一种基于偏振约束的P波时差震源定位方法  

A method of P-wave observed and theoretical travel time differences source location based on polarization constraint

作　　者：赵祥云 李辉 ZHAO Xiangyun;LI Hui(College of Geophysics,Chengdu University of Technology,Chengdu 610059,China)

机构地区：[1]成都理工大学地球物理学院,成都610059

出　　处：《物探化探计算技术》2025年第2期149-158,共10页Computing Techniques For Geophysical and Geochemical Exploration

摘　　要：微震定位是微地震监测技术中最需要解决的问题之一。目前,仅使用P波时差计算震源位置可能会因为多解性产生较大的误差。为了提高定位精度和降低多解性,笔者提出一种基于偏振约束的P波时差震源定位方法。首先根据P波的偏振特征求取震源方位角和倾角,然后用计算的偏振参数对P波时差进行约束来构造目标函数,最后使用粒子群算法求解目标函数进行定位。在理论模型上的测试结果表明,本文方法能极大地降低多解性的问题,经过偏振约束后的定位平均误差从78.5 m降低到0.77 m;在符合本文方法使用条件的实际工区中的测试结果也表明本文方法是一种有效的微震震源定位方法,且该方法仅需少量检波器就能很好地进行定位,结果表明最少只需要5个检波器就能将定位误差控制在1 m以内。Microseismic source location is one of the most important problems in microseismic monitoring technology.using only the P-wave time difference to calculate the source location may cause asignificant error due to multiple solutions.To improve the location accuracy and reduce the multiple solutions,a P-wave source location method based on polarization constraints is proposed.In this paper,the source azimuth and incidence angle are obtained according to the polarization characteristics of the P-wave,and then the Pwave time difference is constrained by the calculated polarization parameters to construct the objective function.Finally,particle swarm optimization is used to solve the objective function for location.The test results on the theoretical model show that the proposed method can greatly reduce the problem of multiple solutions,and the average location error after polarization constraint is reduced from 78.5m to 0.77m.The test results in the actual work area that meet the conditions of the proposed method also show that the proposed method is an effective method for locating microseismic sources.Moreover,the proposed method only needs five geophones to get the location error within 1m.

关 键 词：震源定位 偏振约束 射线追踪 初至拾取 粒子群算法 

分 类 号：P631[天文地球—地质矿产勘探]