中文摘要：

2014年8月3日,在云南鲁甸发生MS6.5地震.该地震位于巴颜喀拉块体、川滇块体与华南块体三者之间的以挤压和左旋走滑为主要活动特征的大凉山次级块体内部.该次级块体吸收了来自川滇块体和巴颜喀拉块体的挤压作用,主要以各边界断裂带的挤压作用和内部大凉山断裂带、峨边断裂带等NNW向的左旋走滑次级断裂为主要特征;在历史上大凉山次级块体边界上以7级以上强震活动为主要特征,而在次级块体内部则以5级地震频繁活动为主.2014年鲁甸MS6.5地震发生在逆冲走滑断裂带内部的NNW向左旋走滑断裂上,该地震主要受到了发生在小江断裂带上的1733年M73/4和则木河断裂带上的1850年M71/2强震的影响,这两次地震对2014年鲁甸MS6.5地震有促进作用,而2014年鲁甸6.5级地震促进了2014年10月1日越西5.0级地震的发生,此外鲁甸地震对大凉山断裂带北段、峨边断裂带、昭通-鲁甸断裂带东段以及则木河断裂带南段有一定的库仑应力增强作用.

英文摘要：

The MS6.5 Ludian earthquake occurred on 3 August 2014 in Yunnan,China.The epicenter of this earthquake is located in the Dalingshan sub-block,a boundary region among the Bayan Har block,the Sichuan-Yunnan block and the South China block,which is dominated by the left-lateral and thrust-slip faults.The studies on the characteristics of the crustal deformation,the mechanism of strong earthquakes and stress changes after the MS6.5 Ludian earthquake in the Daliangshan subblock will help us understand the tectonic implication of the earthquake and facilitate further in-depth studies in the region.This article introduces the slip behavior around the Daliangshan sub-block and strong earthquake distribution on the faults.Using the GPS data in the southeastern Tibetan Plateau,this study analyzes the motions of sub-blocks bordering the Daliangshan sub-block and the slip behavior of the boundary faults in the block model,and estimates the crustal motion in the Daliangshan sub-block after removing the whole block motion of the sub-block.It can be shown clearly that the Daliangshan subblock has absorbed the compression via the Xianshuihe Fault,the Anninghe Fault and the Longmenshan Fault.Due to the compression from the boundary faults,the crustal motion in the subblock is mainly characterized by the north-northwest trending left-lateral strike-slip faults.The boundary faults of the Daliangshan sub-block are mainly characterized by strong earthquakes with magnitude larger than M7 in the history.But in the interior of the Daliangshan sub-block,there are mainly the moderate earthquakes.The MS6.5 Ludian earthquake ruptured the Baogunao-Xiaohe Fault,a left-lateral strike-slip fault associated with the main thrust Ludian-Zhaotong Fault and the Lianfeng Fault,where the whole thrust slip rate of the two faults is about 2.4mm/a.Around the epicenter of the Ludian earthquake,there are strong earthquakes larger than M7 recorded in the nearby region,which might have impact on the occurrence of the Ludian earthquake.Also,the Ludian earthqu