利用哈佛大学GCMT数据中心和前人积累的历史地震资料（1962~2016年M_W>4.0地震）以及Crust2.0地壳结构统计分析了喜马拉雅地区、天山地区的地壳区域构造与地震活动间的相关性。此外，利用GFZ地学研究中心提供的静态卫星重力模型GGM03S/EGM2008和地形模型Topo计算了2个地区的各类重力异常场，同时还模拟了不同地壳弹性参数下的重力异常场，结果表明喜马拉雅地区重力异常场在水平、垂直方向的梯度特征远大于天山地区的异常特征，且喜马拉雅地区的有效弹性板厚度T_e（6~15km）小于天山地区的有效弹性板厚度T_e（20~30km）。最后，利用喜马拉雅地区与天山地区的GPS震间三维形变场约束了断层运动模型，结果显示两者主前缘断裂的断层闭锁深度及应力积累状态存在较大的差异。因此认为，造成青藏高原及邻区的边界地壳区域地震活动性差异的动力学因素，与地壳有效弹性板厚度、孕震断层参数及区域应力积累状态等密切相关。

Firstly,we utilized the historical earthquake events(M_W>4.0(1962-2016))derived from the Harvard University GCMT database,the published papers and the Crust2.0 model to obtain and research their different crustal depth seismicity distributions between Himalaya and the Tienshan by the statistic analysis method. Meanwhile,we used the static satellite gravity models GGM03S/EGM2008 and the TOPO model provided by GFZ Research Center to respectively calculate several different gravity anomaly fields and simulate the free-air gravity anomaly fields and the Bourger gravity anomaly fields basing on the different crustal elastic parameters. The results showed that horizontal and vertical gradient features of the crustal anomaly fields of the Himalayan region is far greater than that of the Tienshan region,and the average effective elastic plate thickness T_e(6-15km),in the Himalayan region,is less than the average effective elastic plate thickness T_e(20-30km),in the Tienshan region. Finally,we used the interseismic GPS 3-D velocity field to constrain and simulate the fault geometry and the kinematic model,and the results showed the great difference of the fault locking depth and the strain accumulation has existed in the different tectonic areas of the Qinghai-Tibetan Plateau,particularly,in the Himalayan Orogenic Belt and the Tienshan Orogenic Belt. Therefore,the crustal seismogenic dynamics of the margin area of the Qinghai-Tibetan Plateau and its adjacent region should have a dramatic correlation with the crustal effective elastic plate thickness;the seismogenic faults geometric and dynamic parameters and the block stress and strain accumulation.

P315

国家自然科学基金重点项目（41630317）资助