强地震前水汽中长期异常变化特征研究  

LONG-AND MID-TERM ANOMALOUS VARIATIONS OF ATMOSPHERIC WATER VAPOR BEFORE STRONG EARTHQUAKE

作　　者：陈梅花[1] 邓志辉[1] 马晓静[1] 陶京玲[1] 王煜[2] 

机构地区：[1]中国地震局地质研究所,北京100029 [2]中国地震局地震预测研究所,北京100036

出　　处：《地震地质》2011年第3期549-559,共11页Seismology and Geology

基　　金：中国地震局地质研究所基本科研业务专项(IGCEA2060302);国家自然科学基金(40841016;40372131;40702056)共同资助

摘　　要：以川西及其邻近地区为例,研究了在强震孕育中长期阶段水汽含量的时空动态特征。通过对2008年汶川8.0级地震、1976年松潘强震群和2010年玉树7.1级地震的分析,发现在川西及其邻近地区的强地震孕育过程中,水汽含量异常频度会出现先下降,然后快速上升的现象。下降开始时间较早,出现在震前10a以上,持续9a以上,属中长期异常信息;而快速上升则发生在震前4a内,属中短期异常表现。地震前水汽含量异常的原因可能是由于岩层中裂隙、孔隙的开合、地下流体的运动和地热能的变化,影响地面温度和潜热交换的分布所致。The spatial-temporal variations of atmospheric water vapor in western Sichuan Province and its vicinity during the mid-and long-term earthquake preparation process are studied.The MS 8.0 Wenchuan earthquake in 2008,the Songpan-Pingwu earthquake sequence in 1976 and the Yushu MS 7.1 earthquake in 2010 are selected as cases of the study regions.The result shows the frequency of atmospheric water vapor anomalies will decrease at first,then increase quickly during the mid-and long-term process of strong earthquake.The decreasing of the frequency of atmospheric water vapor anomalies begins relatively early,mostly over 10 years before earthquake and will last more than 9 years,which is considered as mid-and long-term precursor.The rapid increase appears 4 years before earthquake,as a kind of mid-and short-term precursor.The frequency of atmospheric water vapor anomalies over epicentral region of Wenchuan earthquake began to decline slowly 18 years before the earthquake and continued for 15 years,then increased rapidly 2 years before the earthquake.The atmospheric water vapor anomalies in the epicenter area changed from lowest frequency to high frequency 1 year before the earthquake,then the event occurred.It continued to increase until 2009 then resumed to normal state.14 years before Songpan-Pingwu earthquake,the frequency of atmospheric water vapor anomalies over the epicenter region began declining and it continued for 9 years,and then increased 4 years before the event.The anomalies in the epicenter region changed from lowest frequency in 1971 to high frequency in 1973,and reached the highest in 1976,and then the main shock happened.After the earthquake,it resumed to normal state.Similarly to the above two cases,there had been atmospheric water vapor anomalies before the MS 7.1 Yushu earthquake in 2010,the frequency of anomalies declined from 1997 to 2008 when the lowest value was reached.It increased quickly in 2009 till the event occurred in 2010.The atmospheric water vapor anomalies over epicentral region may be

关 键 词：地震异常 水汽含量 汶川地震 松潘震群 玉树地震 

分 类 号：P315.72[天文地球—地震学]