2016～2017年新疆区域震磁异常信息提取

EXRACT SEISMIC ANOMALY BEFORE XINJIANG EARTHQUAKE FROM 2016 TO 2017

利用极化方法,提取和分析2016年1月1日～2017年10月的垂直分量极化值,分析极化值异常与地震的关系。分析期间发生的5次急始磁暴时的极化值,发现磁场扰动时极化值会出现低值。统计的9次地震,在传播范围内的台站除了温泉台在呼图壁地震之前漏报,其余均出现极化值高值异常。分析结果表明,异常幅度最大的为呼图壁M_S6. 2地震震中距最小(75 km)的乌鲁木齐台,呼图壁地震震级小于精河地震,但是呼图壁地震震中距乌鲁木齐较近,所以就异常幅度而言,呼图壁地震前乌鲁木齐极化值异常大于精河地震前乌鲁木齐台极化值。异常幅度最小的为且末M_S5. 8地震且末台的极化值,可以看到新疆区域的4个台站,且末台的极化值较小,这可能与且末台仪器噪声和背景噪声为全疆最好有关。

Using the method of polarization, extracting and analyzing vertical component of polarization value from 2016 to 2017, analyzes the relations between polarization anomalies and earthquakes. We analyzed the relationship between five geomagnetic storm and polarization values, and found that polarization value would be low when the magnetic field disturbance appeared. In the nine earthquakes in this paper, except for the Wenquan station before Hutubi earthquake, all of the others showed high abnormal value. The largest anomaly amplitude was on December 8th, 2016 Ms 6.2 earthquake and the epicenter distance is minimum （75 km） of Urumqi, although its magnitude was less than Jinghe earthquake, it was close to the epicenter, the anomaly amplitude, polarization anomalies in hutubi was greater than the Jinghe earthquake. The smallest abnormal amplitude of polarization values was in Qiemo station, this may be related to its smallest background noise within Xinjiang.