基于无人机倾斜航空摄影三维点云测量同震倾滑变形研究——以2021年玛多M_(S)7.4地震地表破裂为例  

Measurement of Co-seismic Dip-slip Based on 3D Point Clouds from UAV Oblique Photogrammetry−A Case Study of Surface Rupture of the 2021 Maduo M_(S)7.4 Earthquake

作　　者：李忠武 陈桂华[1] Li Zhongwu;Chen Guihua(State Key Laboratory of Earthquake Dynamics,Institute of Geology,China Earthquake Administration,Beijing 100029,China)

机构地区：[1]中国地震局地质研究所,地震动力学国家重点实验室,北京100029

出　　处：《震灾防御技术》2022年第1期46-55,共10页Technology for Earthquake Disaster Prevention

基　　金：国家重点研发项目(2018YFC1504101)。

摘　　要：2021年5月22日青海玛多发生M_(S)7.4地震,震源断层错动在地表形成了长达160 km的同震地表破裂。可靠的地震地表破裂带参数是研究震源断层活动机制和评价地震危险性的重要基础。采用无人机倾斜摄影测量技术可以获得高精度的点云数据并产出DOM和DEM数据。通过跨破裂带的地形测量,获取了玛多M_(S)7.4地震同震地表变形的垂直位移、水平缩短量和水平拉张量等参数。测量结果显示,玛多M_(S)7.4地震发震断层在不同破裂段具有不同性质和大小的倾滑分量,其中具有压扭性质的野马滩观测点断层垂直位移为0.69~1.01 m,倾向水平缩短量为0.17~0.41 m,倾滑位移为0.71~1.09 m;具有张扭性质的朗玛加合日段断层垂直位移为0.34~0.54 m,倾向水平拉张量为1.99~2.08 m。A M_(S)7.4 earthquake occurred in Maduo,Qinghai,on May 22,2021.The seismogenic fault produced a 160-km-long surface rupture.Reliable parameters of the co-seismic surface rupture are important data for the study on the fault activity and assessment of seismic hazards.In this paper,we generated point clouds,digital ortho-images(DOM)and digital elevation models(DEM)using ob-lique photogrammetry by Unmanned Aerial Vehicle(UAV).Parameters of vertical slip,dip-slip shortening and extension of co-seis-mic slip of the Maduo M_(S)7.4 earthquake were measured from the offset landforms.The results show that the seismogenic fault of the Maduo MS7.4 earthquake is a strike-slip fault with dip-slip in different sections.At the site Yematan,the vertical displacement is 0.69~1.01 m,the dip-slip shortening is 0.17~0.41 m,and the total dip-slip is 0.71~1.09 m.At the site Langma Gaheri,the vertical slip is0.34~0.54 m,and the dip-slip extension is 1.99~2.08 m.

关 键 词：玛多地震 三维点云 无人机倾斜航空摄影 同震倾滑变形 

分 类 号：P315.7[天文地球—地震学] P231[天文地球—固体地球物理学]