新疆阿合奇地震窗异常特征及短期预测效能  

ANOMALY ON AHEQI SEISMIC WINDOW AND SHORT-TERM PREDICTION ON MODERATE-STRONG EARTHQUAKES

作　　者：张琳琳[1] 聂晓红[1] ZHANG Lin-lin;NIE Xiao-hong(Earthquake Agency of Xinjiang Uygur Autonomous Region,Urumqi 830011,Xinjiang,China)

机构地区：[1]新疆维吾尔自治区地震局,新疆乌鲁木齐830011

出　　处：《内陆地震》2022年第2期97-102,共6页Inland Earthquake

基　　金：新疆地震科学基金(202104).

摘　　要：采用新疆阿合奇地震台2008年1月至2020年1月多个台站综合定位获取的地震数据,具体分析M_(L)≥1.0、S_(到时)-P_(到时)≤10 s范围内的微震和小震(简称为微小震)的月频次变化及其与周围地区中强地震的关系。结果显示:①阿合奇地震窗在无异常出现的情况下,微小震月频次处于每月30次左右浮动变化,将微小震月频次超过50次作为异常域值,对南天山西段地区M_(S)≥5.0中强地震具有一定短期预测意义。②当阿合奇地震窗出现异常时,即阿合奇地震窗内微小震月频次超过阈值(50次/月),异常结束后3个月内,南天山西段M_(S)≥5.0中强地震发生的比率为88.89%。③微小震月频度异常形态主要表现为“高值异常—恢复—发震”或“高值异常—发震”。对预测效能评价显示,R值为0.31,R_(0)背景值为0.23,阿合奇地震窗异常对南天山西段地区中强地震具有一定短期预测意义。Taking single digit seismograph records of Aheqi seismic station from January 2008 to January 2020 based on the data of Aheqi single seismic window,writers selected and researched the monthly frequency change of Micro-shock or small earthquakes M_(L)≥1.0 and the S-P value of 10s,as well as their relationship with nearby moderate-strong earthquakes.The results showed that:①the activity frequency of small earthquakes was generally at a moderate level when Aheqi seismic window was under normal circumstances,all the monthly values of which varied at about 30 times,however,when the abnormality with the monthly frequency of Minor earthquakes above 50 emerged,which is of short-term significance to predict medium-strong earthquakes with M_(S)≥5.0.②When the high value anomalies raised,the advantage time for moderate-strong earthquake was within 3 months,the occurrence rate of moderately strong earthquakes with M_(S)≥5.0 in the western part of South Tianshan is 88.89%.③The anomaly patterns of monthly frequency for small earthquakes were characterized by high value-low-earthquake or high value-earthquake.The evaluation of prediction effectiveness shows that the R_(0) value is 0.31 and the R0 background value is 0.23.The study shows that the anomaly of Aheqi seismic window has a certain short-term prediction significance for medium-strong earthquakes in the southern Tianshan section.

关 键 词：新疆阿合奇 地震窗 微小震月频次 预测效能评价R值 

分 类 号：P315.7[天文地球—地震学]