[关键词]
[摘要]
自1966年邢台地震以来,中国尝试用大地测量手段监测地震变形,至1976年唐山地震,变形监测到达高潮,但受地面技术局限,20余年可以用于分析震源的震例寥寥。自20世纪90年代初全面进入空间观测时代以来,境内或边邻6级以上强震大多数有相应的近场变形观测和破裂模型研究,这其中又以2001年昆仑山口西、2008年汶川和2015年廓尔喀3次特大地震的变形资料相对完整、破裂特征清晰、理论成果丰富,成为近期大陆内部最引人注目的大震事件。近30年来,对包括中国台湾在内的60余次强震变形的系统研究丰富了人们对区域地震活动性及危险性的认识,也为青藏高原构造演化研究提供了观测依据与理论参考。半个世纪积累的经验、夯实的基础以及未解的难题更为未来的地震大地测量提供了历史借鉴、前进动力和发展方向。
[Key word]
[Abstract]
Started in 1966 after the Xingtai earthquake,the ground displacements induced by strong earthquakes has been documented by using trigonometrical survey and spirit leveling. The most intensive campaign was implemented for the 1976 catastrophic Tangshan earthquake. Due to the limitation with the conventional methods,only a few of earthquakes have been analyzed geodetically for a kinematic description of their sources in the following twenty years. Since the early 1990s,space geodesy has revolutionized the observation of seismic processes worldwide,and numerous M>6.0 earthquakes in China and adjacent area have been mapped geodetically over subsurface sources for constrain the rupture models. The most successful cases that have sparked a spur of interesting in great ruptures and continental deformation include earthquakes(MS>8.0)of 2001 Kokoxili,2008 Wenchuan and 2015 Gorkha,each of which above has been documented in details about near-field coseismic displacements and well-resolved fault geometries and motions that shed much insights into seismotectonics and physical earthquake. The three-decade-long endeavor of earthquake geodesy in China has yielded the well constrained source models of about 60 major earthquakes in mainland China and Taiwan,from which the study on continental seismicity and seismic risk assessment would be benefit. The gained experience,established monitoring infrastructure and unfulfilled task provide historic references,development platforms as well as orientations to guide continuing geodetic missions.
[中图分类号]
P315
[基金项目]
国家自然科学基金(41731071)资助