新疆前兆群体异常与中强以上地震的短期预测研究  

STUDY ON SHORT-TERM PREDICTION OF MID-STRONG EART-HQUAKES AND XINJIANG GROUP PRECURSOR ANOMALY

作　　者：杨又陵[1] 温和平[1] 高国英[1] 

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》2006年第3期211-218,共8页Inland Earthquake

基　　金：中国地震局"十五"国家攻关项目2004BA601 B010103资助

摘　　要：前兆群体异常是强震前较普遍存在的现象，利用定义的“前兆综合异常比b（t）”，对新疆不同地区、不同档地震前的群体异常特征进；行了研究。在当前的观测条件下，无震时段综合异常比约为0．10～0．20，地震前4～9个月异常比值增大。在异常记录完整条件下，可能出现2次峰值，反映前兆异常发展中的成组特征，峰值异常比：勾0．50～0．70，震前0．5个月前后降到0．30，可能是地震发生的短临信号。7级地震前远场短临异常显著，在缺少近场资料时，强震多发生在群体异常的峰值前后。该方法较客观地描述前兆异常的发展过程，对强地震的短临跟踪具有一定的意义。Group precursor abnorrnaly is a common character before strong earthquakes. We study the group abnormal character before earthquakes with different magnitudes in different regions of Xinjiang with synthetic abnormaly ratio of precursor b （ t ）. Synthetic abnormaly ratio of precursor b （ t ） is about 0.10 - 0.20 during aseismic phase increases during 4 to 9 months before earthquakes. with present observational conditions, which With complete records, there may appear two peak values, which reflects group activity during the evolvement of precursor abnormaly, and peak value of b （ t ） is 0.50 to 0.70, and drops to 0.30 about half a month before earthquake, which may be short-impending signals of earthquake occurrence. Far-field short-impending abnormaly is obvious before M7 earthquake, most strong events occur before and after peak values of group abnormaly with few near-field data. The method depicts the evolvement of precursor abnorrnaly objectively, and is significant for short-impending track of strong earthquakes

关 键 词：新疆 前兆群体异常 短临预测 前兆综合异常比 

分 类 号：P315.75[天文地球—地震学]