【摘要】 为了研究大震(Ms≥7)和巨震(Ms≥8)与重力异常和活动断裂的关系.利用EIGEN-6C重力模型计算了相关地区的自由空气重力异常,查阅了相关地区的布格重力异常和活动断裂构造.分析了重力异常突变带和活动断裂带与这些地震的空间分布.发现大震和巨震常在重力异常突变带和活动断裂带交汇处发生.结合前人对地球深部构造特征的研究,提出了一种流变模型来解释大地震发生于重力异常突变带和活动断裂带交汇处的原因:地壳深部流变层(体)流动受阻碍而引起重力异常和能量积累与释放.更多还原

【Abstract】 In order to find the relationship among a large(Ms≥7)earthquake,or a giant earthquake(Ms≥8)and the steepest gradient of gravity field and active fault,the free air gravity anomaly map by EIGEN-6Cgravity model was calculated,the bouguer gravity anomaly and active fault of the region trends to occur large or giant earthquake is consulted.The spatial distribution of large and giant earthquakes and active fault,gravity anomaly is analyzed.We come to a conclusion that a large or giant earthquake trends to occur at the intersection area of steepest gradient of gravity field and active fault.With the previous study of deep structures in those area,we propose a rheological model to interpret the regularity.It is that the flow of the rheological layer(body)blocked by the brittle rocks cause the gravity anomaly and energy accumulation and release.更多还原