华北地块及邻区重力异常特征及地质结构  

Gravity anomaly characteristics and geological structure of the North China block and its surrounding areas

作　　者：郭雨帆 肖健 付光明 许志山 李清武 黄仁桂 赵影 徐长文 肖建华 袁俊 GUO Yufan;XIAO Jian;FU Guangming;XU Zhishan;LI Qingwu;HUANG Rengui;ZHAO Ying;XU Changwen;XIAO Jianhua;YUAN Jun(Jiangxi Earthquake Agency,Nanchang 330096,Jiangxi,China;Hebei Key Laboratory of Earthquake Disaster Prevention and Risk Assessment,Sanhe 065201,Hebei,China)

机构地区：[1]江西省地震局,江西南昌330096 [2]河北省地震灾害防御与风险评价重点实验室,河北三河065201

出　　处：《地震工程学报》2023年第5期1075-1084,共10页China Earthquake Engineering Journal

基　　金：河北省地震灾害防御与风险评价重点实验室开放基金资助项目(FZ223205)。

摘　　要：研究华北地块及邻区重力异常特征、地质结构和断裂构造,对该区地震风险研判和矿产资源远景规划具有重要意义。文章基于小波多尺度分解法、Parker-Oldenburg迭代反演法和重力异常导数法,利用华北地块及邻区布格重力异常数据,获得布格重力异常小波分解逼近场和细节场、莫霍面深度和重力异常导数。结果表明:(1)逼近场和细节场揭示出华北地块可分为西部的鄂尔多斯克拉通块体和东部的华北似环状裂谷盆地两个子单元。(2)莫霍面深度范围在28~52 km之间,呈NNE走向,由西向东逐渐变浅,具有显著的“东西分带”特征。尤为显著的是鄂尔多斯克拉通块体和华北似环状裂谷盆地,块体内部莫霍面变化较平缓,块体边界莫霍面变化剧烈。(3)根据重力异常导数结果识别并校正出研究区13条块体边界及主要断裂带。Examining the gravity anomaly characteristics,geological structure,and fault structure of the North China block and surrounding areas is significant for assessing earthquake risk and long-term mineral resource formation in this region.Based on the Bouguer gravity anomaly data from the North China block and surrounding areas,the wavelet approximations and details of the Bouguer gravity anomaly,Moho depth,and gravity anomaly derivatives are obtained via multiscale wavelet decomposition,Parker-Oldenburg iterative inversion,and gravity anomaly derivative methods.The key results are as follows:(1)the wavelet approximations and details show that the North China block can be divided into two subunits,namely,the Ordos Craton block in the west and the North China ring-like rift basin in the east.(2)The Moho depth is in the range of 28-52 km;it strikes NNE and gradually decreases from west to east,with obvious“east-west zoning.”In the Ordos Craton block and the North China ring-like rift basin,the Moho depth inside the block remains stable,whereas that below the block boundaries changes drastically.(3)Thirteen block boundaries and major fault zones in the study area are identified and corrected based on the derivative results of gravity anomaly.

关 键 词：华北地块 重力异常 莫霍面 断裂 

分 类 号：P315[天文地球—地震学]