鄂尔多斯块体西北缘层析成像研究  

Research on Tomography in the Northwest Margin of the Ordos Block

作　　者：王禄军 高磊 郝美仙[1] 尹战军[1] 韩晓明[1] WANG Lujun;GAO Lei;HAO Meixian;YIN Zhanjun;HAN Xiaoming(Earthquake Agency of Inner Mongolia Autonomous Region,80 Jirem Road,Hohhot 010010,China;School of Earth and Space Sciences,University of Science and Technology of China,96 Jinzhai Road,Hefei 230026,China)

机构地区：[1]内蒙古自治区地震局,呼和浩特市010010 [2]中国科学技术大学地球和空间科学学院,合肥市230026

出　　处：《大地测量与地球动力学》2024年第12期1275-1279,共5页Journal of Geodesy and Geodynamics

基　　金：内蒙古自治区地震局局长基金(2023MS06)。

摘　　要：基于内蒙古测震台网记录的数字地震观测报告,使用3398个M≥1.0地震的Pg波和Sg波数据,采用双差层析成像方法对鄂尔多斯块体西北缘(37°~43°N,104°~110°E)地下结构进行研究,并对地震进行重定位,同时对该区上地壳速度结构进行详细分析。结果表明,从Pg波速度结构来看,5~10 km深度从东北到西南对角线存在不规则的连续高速体,15~20 km深度高速体不再连续,而呈散状分布;从Sg波速度结构来看,5 km和15 km处基本与Pg波速度结构一致,10 km和20 km处低速区分布较多且地震多发生在高低速体交界处和断裂周围,表明该区地壳的脆弱性。Based on the digital seismic observation report recorded by the Inner Mongolia seismological network,using Pg and Sg wave data of 3398 earthquakes with M≥1.0,we deploy the double-difference tomography method to study the underground structure in the northwest margin of the Ordos block(37°~43°N,104°~110°E)and conduct the earthquake relocation.At the same time,we analyze in detail the velocity structure of the upper crust in the area.The results show,from the velocity structure of Pg wave,there is a continuous irregular high-speed body from northeast to southwest at 5 to 10 km,and the high-speed body at 15 to 20 km is no longer continuous but scattered.From the velocity structure of the Sg wave,the velocity structure at 5 km and 15 km is basically consistent with that of the Pg wave.There are more low-speed areas at 10 km and 20 km,and earthquakes mostly occured at the junction of high and low velocity bodies and around faults,which proves the fragility of the crust in this area.

关 键 词：鄂尔多斯块体西北缘 双差层析成像 重定位 速度结构 

分 类 号：P315[天文地球—地震学]