地震工程学报2016，Vol.38Issue(z2)：203-207,5.DOI:10.3969/j.issn.1000-0844.2016.Supp.2.0203
2013年岷县6.6级地震前天水台磁通门秒数据异常提取分析
Extraction and Analysis of Anomalies of the Second Datafrom GM4 Fluxgate Magnetometer at TianshuiStation before the 2013 Minxian MS6.6 Earthquake
摘要
Abstract
On July 22, 2013, an earthquake occurred in Minxian County, Gansu Province, whose epicenter was located 154 km from the Tianshui seismic station.Geomagnetic three-component second sample observations at Tianshui station were initiated in 2007 through a GM4 fluxgate magnetometer.Here, we analyze the change of the geomagnetic polarization value and the transform function at Tianshui station from 2008 to 2014 based on the second data of GM4 fluxgate magnetometer.The results indicate that the geomagnetic polarization value and the transform function show different degrees of anomaly before the Minxian MS6.6 earthquake.(1) The transform function exhibited down turning recovery before the earthquake.In fact, the earthquake occurred just as the transform function reached the maximum.(2)The short-term increase was more obvious than the long-term trend, and the rising amplitude was larger.(3) Before the earthquake,the Parkinson vector azimuth in the periods of 20 s, 50 s, and 80 s was rotated and directed to the epicenter.(4) In April 2013, three months before the earthquake, the geomagnetic polarization at Tianshui station showed two anomalies of high values exceeding three times the mean square deviation.关键词
地磁场/秒采样/转换函数/极化/地震Key words
geomagnetic field/second sample/transform function/polarization/earthquake分类
天文与地球科学引用本文复制引用
倪晓寅,冯志生,陈莹..2013年岷县6.6级地震前天水台磁通门秒数据异常提取分析[J].地震工程学报,2016,38(z2):203-207,5.基金项目
2015年度震情跟踪定向工作任务"基于秒数据的地磁转换函数强震前变化特征研究"(2015010407) （2015010407）
