地质学报Issue(8)：1401-1416,16.
青藏高原东南缘现今大震活动特征及其趋势：活动构造体系角度的初步分析结果
The Seismic Hazard Assessment around South-East Area of Qinghai-Xizang Plateau:A Preliminary Results from Active Tectonics System Analysis
摘要
Abstract
There is a mega-tectonic system in south Asia,which is called South Asia “Z”shaped tectonic system in Lee’s geomechanics theory.Its range mainly involves Qinghai-Tibet,Yunnan,Myanmar and Indonesia. The present activity of the tectonic system is very prominent and controls many large earthquakes (M≥6. 8)distribution,so it is a typical active tectonic system.Based on recent studying on active faults and earthquake geology,we analyzed in detail the present activity and large earthquake events since 1320 A.D. along the active tectonic system.The studying results show that the consistency aspects of kinematics and large earthquakes chain reaction or domino effect resulted from active fault interaction are all very obvious along different structure segments of the mega-tectonic system.The interaction effect of large earthquakes is that the middle segment occurred immediately large earthquake events soon after (usually about few months or few years,and sometimes more than ten years)some large earthquakes occurred along the head of tail of the South Asia “Z”shaped mega-tectonic system.But during the latest large earthquake cycle since 1997 A.D.,the Sichuan-Yunnan constituting the middle segment of the tectonic system,which is a typical active province of large historical earthquakes in west-south China,appeared aseismic period of large earthquakes sustainable more than ten years after many large earthquakes occurred along the head and tail segment of the tectonic system.The long large earthquakes quiescence occurred in middle segment is obviously incompatible with the interaction effect of large earthquakes of the South Asia “Z”shaped tectonic system,and implies that there is very high large earthquake hazard in the near future at the middle structure segment.Based on the newest active faults studying on Sichuan-Yunnan arc rotation-shearing active tectonic system combining with three fundamental criterions of seismic hazard assessment,including elapsed time after large earthquake events,seismic gap and chain reaction or domino effect of large earthquake events,we suggest that there are 9 large earthquake high hazard areas or belts in the Sichuan-Yunnan arc active tectonic system,including:Anninghe segment of the Xianshuihe-Xiaojiang fault zone, Qiaojia segment of the Xianshuihe-Xiaojiang fault zone,the southern section of the Xiaojiang fault of the Xianshuihe-Xiaojiang fault zone,Heqing-Songgui graben basin and the Chenghai-Binchuan fault in rifting zone of the west-north Yunnan,the seismic gaps along the Wanding fault and Nantinghe fault,the east-south segment of the Lancang-Jinghong fault zone,Yuanmou graben and Baoshan graben.The new seismic hazard assessment results are helpful to understand present large earthquake trend on the Shichuan-Yunan active tectonic system of west-south China.关键词
地质力学/活动构造体系/青藏高原/川滇强震区/大地震危险性Key words
geomechanics/active tectonics system/Tibet Plateau/large earthquake activity/seismic hazard assessment引用本文复制引用
吴中海,赵根模,龙长兴,周春景,范桃园..青藏高原东南缘现今大震活动特征及其趋势：活动构造体系角度的初步分析结果[J].地质学报,2014,(8):1401-1416,16.基金项目
中国地质调查局地质调查项目青藏高原东南缘重要活动断裂厘定与活动构造体系综合研究（1212011120163）；国家自然科学基金（41171009）；基本科研业务费成果集成与战略研究（2014～2015）（DZLXJK201410）共同资助成果。 （）
