川滇地区极低频电磁场分布特征及异常信息分析研究

The electromagnetic(EM) observation is a effective method in many earthquake monitoring methods, and the electromagnetic anomalys before earthquake have been observed. The EM observation will be expected to get breakthrough progress in earthquake monitoring. In this study, the data obtained at 15 EM in SLF frequency band observatories and mobile observations for natural source and artificial source in Sichuan and Yunnan province region will be processed, analysed and done statistics. Study onfield temporal and spatial variation characteristics of the electromagnetic field background, the variation characteristics of EM fields in SLF frequency band for typical geomagnetic events (e.g. geomagnetic storms, solar activities, etc.) , the study on spatial distribution of electromagnetic effects during seismic activity, before the earthquake, seismic and post seismic; And study on the relationship between electromagnetic anomaly and conducivity structure below the observation station. The study will service earthquake prediction ang provide basic data accumulation.

在众多的地震监测方法中，电磁观测是十分有效的观测方法，地震前电磁异常现象被大量观测到, 并有望在地震预测中取得突破性进展。本项研究，将利用川滇地区15个极低频电磁观测台站和流动观测台接收的天然源和人工源电磁场观测数据，对观测资料进行处理、分析和统计，开展极低频电磁场时空变化特征研究，分析典型地磁活动事件（磁暴、太阳活动等）期间的极低频电磁场的变化特征，研究地震活动的震前、同震和震后的电磁效应及其空间分布规律；研究电磁场异常变化和观测台站的地下结构的关系等，为地震预测预报提供服务和基础资料的积累。

利用川滇地区15个极低频电磁观测台站和3~4个流动观测台接收的天然源和人工源电磁场观测数据，开展极低频电磁场时空变化特征研究，分析典型地磁活动事件期间的极低频电磁场的变化特征，研究地震活动的震前、同震和震后的电磁效应及其空间分布；采用小波变换和傅式拟合获取了电磁场背景变化，提取和分析了电磁异常信号及其特征，及时分析了几次中强地震的前兆电磁异常信息特征，并在地震前的提出了电磁异常的会商会意见；研究了电磁场异常变化和观测台站的地下结构关系；基于地震电磁前兆异常分析，概括性总结了地震前兆异常的地下结构变化和电磁场的影响距离及其异常机理。