相关检测技术在低频交流地电阻率观测中的应用

Application of correlation detection technology in low-frequency AC geo-resistivity observation

目前我国的地震地电阻率观测主要采用单一极距四极对称装置的直流观测测方法,该观测越来越多的受到城市建设中出现的各种电磁干扰的影响,特别是地铁、轻轨等的干扰,使得观测数据严重超差.为此我国的地震工作者提出了交流地电阻率观测方法,该方法由于采用固定频率信号进行观测,可以抑制人文干扰.本文对低频交流地电阻率观测中所采用的相关检测技术原理及在观测系统研制中的应用进行了阐述,并采用数值模拟方法对相关检测技术及观测系统参数选择进行了详细分析,研究了在不同参数条件下的相关检测误差及影响因素,给出了观测系统主要性能指标的基本要求和设计参数,为观测系统研制提供基础和依据.

The observation systems of earthquake-related geoelectrical mainly use the four-electrode symmetry configuration.But more and more stations are in the environment with strong interferences,especially subway and light rail.The variance of daily average of the geo-electrical resistivity is out-of-tolerance in affected monitoring stations.For this reason,lots of researchers are working on researching AC geo-resistivity observation.Owing to using the fixed frequency signal to detect geo-resistivity,human interference can be suppressed.In this paper,elucidated the theory of correlation detection technology and the application in lowfrequency AC geo-resistivity observation.Then analyzed the correlation detection method by did numerical simulation.Through the studied the results of simulation,given the key performance indicators and design parameters of observation system.This is the basis on which development of lowfrequency AC geo-resistivity observing system.