我国105°E以东地区M_S≥5.7级地震的孕震3步曲  

Three stages of earthquake (M_s≥5. 7) gestation in 105°E east of China

作　　者：汤懋苍[1] 梅秀苹[2] 郭维栋[3] 

机构地区：[1]中国科学院寒区旱区环境与工程研究所,甘肃省干旱气候变化与减灾重点实验室,兰州730000 [2]中国地震局兰州地震研究所,兰州730000 [3]南京大学大气科学学院,南京210093

出　　处：《地球物理学进展》2011年第4期1141-1146,共6页Progress in Geophysics

基　　金：国家973计划(2008CB425704);国家自然科学基金面上项目(40975049)资助

摘　　要：根据近30年来,我国105°E以东(包括大陆架)M_s≥5.7级地震的震前逐月地温和降水演变特征,可以归纳出震前地气系统演变的共同特征:(1)可将"干热面积"最大月定为孕震3步曲的第一步.未来震级与干热面积有好的相关,最干点的经纬度与震中经纬度有一定的相关;(2)从地温、降水应变波出现到"正多负少"规则恢复可以作为孕震第二步的开始;(3)降水经向波长开始明显变长(甚至变为无限长),可称为孕震第三步,此时距地震发生仅剩0～2个月的时间.外核对流上升体(孕震体)对壳幔层顶托作用的地震成因说,可以较好地解释上述观测事实.To understand the relationship between atmosphere and lithosphere system deeply, we analyzed data of monthly ground temperature and precipitation and summarized common features of the evolution of climate system before the earthquake with Ms≥ 5.7 over the past 30 years which occurred in the 105°E east of China. The main statistical results are： （1） The first stage of the earthquake gestation is the month with the maximum value of abnormal high soil temperature area. The following magnitude of earthquake is well related with the abnormal high soil temperature area. The driest position has some relationship with the epicenter. （2） The second stage starts from the appearance of the fluctuation in both the oil temperature and precipitation fields to the restoration of the ＂more rainfall when positive change of soil temperature and less when negative＂ rule. （3） The wavelengths of precipitation stress wave along longitude become longer （or even become infinite） is the third stage in the 0 to 2 months before earthquake. A hypothesis is proposed on the mechanism of strong earthquake can well explain the observed phenomenon： There is a kind of unstable uplifting Benard convection in outer layer of the earth core. The uplifting actions push up the crust and the mantle.

关 键 词：干热异常 地温波 降水波 应变弱停 

分 类 号：P315[天文地球—地震学]