一种前兆效能更好的地电阻率观测装置讨论

Earth Resistivity Observation Installation with Better Earthquake Precursor Detection Efficiency

介绍近年来甘肃深井地电阻率(ρs)实验观测的资料和震例,证明SA(甘肃单孔深井垂直观测方案)是一种前兆效能更好的方案。文中从水平层状介质的角度解释更好的机制和原理,定量估算几种装置的前兆效能,结果表明:(1)在平凉深井台站,SA装置的前兆效能是深井水平向装置的3.3倍;(2)在兰州观象台,新建的SA装置完整地记录到一个震例(异常时间段50d,其中短临时间段10d,异常变幅2.4%),而原有地面观测装置不能分辨该震例。从地面观测到深井水平向观测,解决了最棘手的电磁干扰问题,使ρs曲线成形连续;从深井水平向观测到SA方案,解决装置的前兆效能问题和最突出的季节性年变问题,使震例的特征清晰可见。文中针对需求介绍SA装置构建的方案。观测资料表明:SA方案是解决当今电磁干扰问题的最佳途径,是提高装置前兆效能的方向。

In this paper,the data and seismic examples of the deep-well geo-electrical resistivity experiments in Gansu province in recent years are introduced,and SA scheme(vertical observation scheme of single-hole deep well in Gansu)is proven to have better earthquake precursor detection efficiency.The mechanism and principle of the scheme is explained from the perspective of horizontal layered medium,and the prediction efficiencies of various installations are quantitatively estimated.The analysis holds that SA is the best approach to solve the electromagnetic interference problem,in order to improve the precursor detection efficiency of installations.