芦山Ms 7.0级地震震前及同震地表形变  

Pre-seismic and Co-seismic Deformation of Ms 7.0 Earthquake in Lushan

作　　者：杨国华[1] 朱爽[1] 梁洪宝[1] 杨博[1] 

机构地区：[1]中国地震局第一监测中心,天津300180

出　　处：《武汉大学学报（信息科学版）》2015年第1期121-127,共7页Geomatics and Information Science of Wuhan University

基　　金：中国地震局公益性地震行业科研专项资助项目(201308009;201208006);国家科技支撑计划资助项目(2012BAK19B01-02);中国地震局芦山7.0级强烈地震科学考察资助项目~~

摘　　要：对四川地区GNSS观测数据进行处理,获得如下结果:1汶川Ms 8.0级地震之前龙门山断裂带及其以北近150km的范围内几乎不存在可分辨的右旋走滑活动和压性形变,四川盆地以西-鲜水河安宁河断裂带以东约100km的范围内几乎也不存在可辨的形变;2汶川Ms 8.0级地震之后芦山Ms 7.0级地震之前,龙门山断裂带中、北段存在约5mm/a右旋走滑活动,芦山震源及附近地区的三维形变一直处在闭锁状态,鲜水河安宁河断裂带及其以东的左旋形变有所增强;3芦山地震可变的同震形变场基本分布于以震源为中心的数十km范围内,大致以震中为界东侧呈右旋形变,西侧呈左旋形变;4距震中较近约12km的LS05震时"永久性"垂向位移量约7cm,水平向逆冲量约4cm,走滑量约5cm。Based on the GNSS data processing results from the Sichuan area, following conclusions are obtained ： ① Before the Ms 8.0 earthquake in Wenchuan, there was almost no dextral strike-slip activity distinguished or compressional deformation on the Longmenshan fault zone and nearly 150 km north of it, and was deformation distinguished in the area of 100 kms west of Sichuan Basin the Xianshuihe Anninghe Fault.② Between the Ms 8.0 earthquake in Wenchuan and Ms 7.0 earthquake in Lushan, there was about a 5 mm/a dextral strike-slip activity in the middle and northern sections of the Longmenshan fault zone, with no 3D deformation distinguished in and near the seismic source region. Meanwhile the sinistral deformation increased on the Xianshuihe Anninghe fault and east of the zone.③The co-seismic deformation field of the Lushan earthquake was basically distributed for 10 kilometers around the seismic source region, with an epicenter bounded ,on the east side as a dextral deformation, on the west side with a sinistral deformation. ④ LS05 was about 12 km to the epicenter; the permanent vertical displacement momentum was around 7 cm, with a horizontal thrust momentum of about 4 cm, the horizontal strike-slip was about 5 cm from the station.

关 键 词：芦山地震 同震位移场 震前运动场 震时位移 GNSS 

分 类 号：P227[天文地球—大地测量学与测量工程]