利用地震震源机制资料和形变场模型估算中国大陆及其邻区的地震矩亏损

• 作 者: 李长军 任金卫 孟国杰 秦姗兰 付广裕 杨攀新
• 机 构: 中国地震局第二监测中心,中国地震局地震预测研究所,
• 出 处: 地球物理学进展
• 发表日期: 2015年06期
• 关键词: 地震矩 双三次样条函数 地震分段 地震危险性 联合反演 地震震源 鄂尔多斯块体 大震 阿尔金断裂带 鲜水河断裂带

前人利用历史地震资料、第四纪活断层资料和GPS等资料联合反演了中国大陆及其邻区的运动学模型,为分析研究区域的地震危险性提供了基础资料.本文基于前人研究中对7级及其以上大震地震矩使用中存在的问题,详细搜集整理了研究区域47个7级及其以上大震的震源参数、破裂带资料和地表位移资料,并利用这些资料将大震分段.再利用历史地震资料和联合反演的形变场模型估算了研究区域的地震矩亏损,并从中扣除10%的非震形变.最后,根据估算的地震矩亏损结合前人的研究成果讨论了研究区域的地震危险性.结果表明:113年间地震矩亏损较大的区域主要包括喜马拉雅断裂带、天山、阿尔金断裂带、柴达木盆地北缘、青藏高原中南部、鲜水河断裂带南段、安宁河断裂带、则木河断裂带、红河断裂带、龙门山断裂带北段和南段、鄂尔多斯块体周缘、东南沿海和贝加尔裂谷带等,前人的研究结果表明上述部分区域未来存在发生强震的可能.

The predecessors used the historical seismic data, quaternary active fault data and GPS data to jointly retrieve the kinematics model of the Chinese mainland and its adjacent areas, and provide the basic data for analyzing the seismic risk in the study area.Based on the previous studies In the use of seismic moment of magnitude 7 and above, the source parameters, rupture zone data and surface displacement data of 47 large earthquakes of magnitude 7 and above in the study area were collected in detail and the data The seismic moment loss is estimated by using the historical seismic data and the joint deformation model of the joint inversion, and deducting 10% of the unsteady deformation losses from the study area.Finally, based on the estimated earthquake moment loss combined with previous research results The seismic risk of the study area is discussed.The results show that the areas with large loss of seismic moment in 113 years mainly include Himalaya fault zone, Tianshan Mountains, Altyn Tagh fault zone, northern margin of Qaidam Basin, central-southern Qinghai-Tibet Plateau, Xianshuihe fault Southern section, Anninghe fault zone, Zemuhe fault zone, Honghe fault zone, northern segment and southern segment of Longmenshan fault zone, block periphery of Ordos, southeast coast and Rift Gard et al., Previous studies indicate that the presence of strong earthquakes possible future partial region.