2011—2014年康定周边地形变场变化与芦山7.0级地震及康定两次中强地震的关系研究

Relationship between Crustal Deformation Field Changes in the Periphery of Kangding Area During 2011—2014,the Lushan 7.0Earthquake,and Two Subsequent Earthquakes in Kangding

收集康定地震区及周边(99.6°~105.2°E,27.8°~33.0°N范围内)连续GPS观测站的资料求解站速度场,采用刚性-线弹性运动方程计算方法,拟合计算得到研究区域规格网格点(0.4°×0.4°)的速度值和主应变率值。基于该结果分析研究区内的运动特征和应变场变化情况,并讨论其与地震孕育发生的关系。分析结果表明,芦山7.0级地震发生前研究区呈现应变能量积累态势,而地震之后研究区呈应变能量释放调整态势,2014年康定地震的发生就是该区构造运动调整下的产物。

Based on highly precise GPS data,this paper investigates the relationship between the Kangding earthquakes（M W6.3and M W5.8,in November 2014）and the changes in crustal movement and strain energy in the surrounding area.First,the data was collected from continuous GPS observation sites in the Kangding seismic and surrounding regions（99.6°—105.2°E,27.8°—33.0°N）.We then calculated the velocity at the observation sites and determined the crustal movement and principal strain rate fields for specific grid points（0.4°×0.4°）using the fitting calculation of a rigid-linear elastic motion equation.Second,based on the obtained results,we discuss the movement field characteristics and strain field changes in the Kangding seismic region and explore their relationship with earthquake preparation.The results show that the study area is associated with strain energy accumulation prior to the Lushan MS7.0earthquake in 2013.In contrast,the area exhibits strain energy release and adjustment after the Lushan earthquake.It is proposed that the Kangding earthquakes are a product of tectonic adjustment in the study area.