2012年宁蒗—盐源5.7级地震前的重力变化  

Gravity Variation before Ninglang-Yanyuan M_S5.7 Earthquake in 2012

作　　者：郑兵[1] 王青华[2] 罗海元[1] 马伶俐[1] 蒲晓霞[1] 李菲菲[1] 苏琴[1] 

机构地区：[1]四川省地震局测绘工程院,四川雅安625000 [2]云南省地震局,云南昆明650300

出　　处：《地震研究》2015年第3期370-376,517,共7页Journal of Seismological Research

基　　金：四川省重点"项目高精度智能测量机器人跨断层位移测量实验"(LY1406);"基于GPS;重力测量对龙门山断裂带芦山剖面跟踪分析"(LY1506);地震科技星火计划攻关项目"川滇地壳形变特征及在强震中短期预测中的应用研究(XH15037SX)共同资助

摘　　要：利用2010年7月-2012年3月四川省和云南省的流动重力观测数据,对2012年6月24日宁蒗—盐源5.7级地震孕育和发生过程中的重力场动态演化情况进行分析。结果显示：地震孕育阶段震中区域重力场出现大面积的重力正值变化高值异常区域,并形成密集的正值变化梯度带;震前震中区域呈重力正变化低值状态,处于重力变化0值线附近且等值线稀疏;震前与发震有关的断裂带的跨断层重力测段段差值变化明显。Using the flow gravity observation data in Sichuan and Yunnan provinces from Jul.,2010 to M ar.,2012,we analyzed the gravity field dynamic evolution in the process of preparation and occurrence of Ninglang-Yanyuan MS5. 7 earthquake on Jun. 24,2012. The results showed that in the process of earthquake preparation,a large area of high value anomaly of gravity positive changes appeared and formed to the intensive gradient belt of gravity positive in the area of epicenter. Before the earthquake,the epicenter region appeared the low value anomaly of gravity positive changes,where was near to the 0 contour line of the gravity field and the sparse contour line,and the variation in segment differences of the gravity across the fault zone which induced the earthquake was obvious.

关 键 词：流动重力测量 重力场 川滇地区 宁蒗—盐源5.7级地震 

分 类 号：P315.7[天文地球—地震学]