中文摘要：

利用青藏高原东北缘2011-2013年期间的流动重力观测资料,系统分析了区域重力场动态变化及其与2013年7月22 H岷县漳县6.6级地震发生的关系.结果表明：1）测区内重力场异常变化与主要断裂带在空间上关系密切,反映沿主要断裂带（段）在2011-2013年期间发生了引起地表重力变化效应的构造活动或变形.2）岷县漳县6.6级地震前,测区内先出现了较大空间范围的区域性重力异常,后在震源区附近产生了局部重力异常及重力变化高梯度带,其中,甘肃临夏与岷县一带重力差异变化达150×10 8ms-2以上;这些可能反映岷县漳县地震前,区域及震源区附近均产生与该地震孕育、发生有关的构造运动或应力增强作用.3）重力场1a尺度动态变化图像和差分动态演化图像均反映岷县漳县6.6级地震孕育过程的最后2a出现较显著的流动重力异常变化,地震发生在NE向重力变化高梯度带上、重力变化零值线附近和等值线的拐弯部位.4）基于流动重力异常变化在岷县漳县6.6级地震前做过一定程度的中期预测,尤其是地点判定.

英文摘要：

Using the observation data of relative gravity measurements from the northeastern edge of the Tibetan plateau,we have systematically analyzed the spatial-temporal variation of the regional gravity field and their relation to the occurrence of the MS 6.6 Minxian-Zhangxian earthquake on July 22,2013.Our research mainly shows that：1）Spatially the anomaly change of the regional gravity field is closely related to the major fault zones in the region,suggesting that the tectonic activities or deformation which happened along the fault zones（or segments）during 2011 to 2013 would have resulted in the variation in the ground gravity observations.2）Before the MS 6.6 Minxian-Zhangxiang earthquake,regional gravity anomaly firstly appeared in the whole study region,and then local gravity anomalies and high gradient zone of gravity change appeared at and near the potential source area.Among the areas of gravity anomalies,the anomaly variations near Linxia and Minxian were up to and over 150×10-8ms-2,indicating possibly the tectonic movement or stress enhancement in the study region and around the potential source area,which could be related to the preparation and occurrence of the earthquake.3）The dynamic change patterns and the differential evolution patterns of gravity variation of one year scale suggest that significant anomalies of gravity variations in the mobile gravity measurements appeared indeed in the last two years of the preparation process of the MS 6.6 Minxian-Zhangxian earthquake.The earthquake occurred on the NE-trending high gradient zone near the zero curve and the turning part of contours of gravity change.4）To a certain degree,we made a mediumterm forecast before the Minxian-Zhangxian MS 6.6 earthquake,especially a forecast for the locality of the earthquake based on the anomalous gravity variations.