文章摘要

文章信息/Info

Title:: Quiescence Anomalies of M≥6.0 Earthquakes before the 2008 Wenchuan(M8.0)Earthquake in Sichuan-Yunnan Region

Author(s):: SU You-jin ¹; LIU Jie²; (1.Earthquake Administration of Yunnan Province,Kunming 650224,Yunnan,China)(2.China Earthquake Networks Center,CEA,Beijing 100036,China)

摘要:: 2008年5月12日四川汶川8.0级地震前,川滇地区出现了显著的地震平静异常:M≥6.0、M≥6.5和M≥7.0地震平静时间分别达3.63年、8.29年和12.27年。通过对1900年以来川滇地区M≥6.0、M≥6.5和M≥7.0地震时间分布特征的统计分析,发现这些平静异常现象在川滇地区近100年来的地震活动性中是非常显著的。在M≥7.0地震平静时间大于5年的条件下,M≥6.0(1.0σ以上)和M≥6.5地震(1.5σ以上)平静异常在统计上具有显著性和重现性,可能是这类7级地震前一个重要或典型的异常现象。

Abstract:: It appeared seismic anomaly quiescence before the Wenchuan earthquake(M=8.0),May 12,2008,in Sichuan-Yunnan region.The quiescence time for the earthquakes with M≥6.0,M≥6.5 and M≥7.0 is about 3.63 years,8.23 years and 12.27 years respectively.By the systematic analysis of the time distribution features for the earthquakes with M≥6.0,M≥6.5 and M≥7.0 from 1900 to 2008 occurred in Sichuan-Yunnan region,the results presents these quiescence anomalies are the very prominent in the past 100 years seismicity in this region.It also presents that the quiescence anomalies for the earthquakes with M≥6.0(above 1.0σ)or M≥6.5(above 1.5σ),have notability and universality when the quiescence time for the earthquake with M≥7.0 is above 5 years.Therefore,it could be an important or typical phenomena before this type earthquakes with M≥7.0 in Sichuan-Yunnan region.