1∶20万区域重力调查成果分析——以可可西里湖地区为例  

Analysis of 1∶200000 Regional Gravity Survey Results--An Example of the Hoh Xil Lake Area

作　　者：朱将波 陈社教[1] 汪启年[1] Zhu Jiangbo;Chen Shejiao;Wang Qinian(Anhui Geological Exploration Technologies Insitute,Hefei Anhui 230031,China)

机构地区：[1]安徽省勘查技术院,安徽合肥230031

出　　处：《工程地球物理学报》2024年第3期433-442,共10页Chinese Journal of Engineering Geophysics

基　　金：国家重点研发计划(编号:2018YFC060360600);中国地质调查局地质调查工作项目(编号:1212010818012)。

摘　　要：可可西里湖地区位于青藏高原北部,地质工作程度较低,为认识测区主要地层展布、断裂构造、岩浆岩及沉积盆地分布,在可可西里湖地区开展1∶20万区域重力调查,进行数据处理和综合研究,结果表明:本区地壳趋于均衡补偿,莫霍面与地势大致呈“镜像”关系;共推断断裂21条,东昆仑南断裂是西域板块和华南板块的边界,其以北地区莫霍面快速抬升,东昆仑中断裂位置较以往偏北约12 km;圈定侵入岩10处,主要在东昆仑中缝合带发育;识别中新生代沉积盆地9处,并反演底界面埋深变化,楚玛尔河盆地新生界厚度在2000 m以上;在速度结构和电性结构约束下,通过重力2.5维定量反演建立了地质地球物理剖面模型,分析了主要构造单元的地质特征,同时初步划分金属矿找矿远景区4处。The Hoh Xil Lake area is located in the northern Tibetan Plateau,with a relatively low degree of geological work.In order to understand the main stratigraphic distribution,fault structure,magmatic rock and sedimentary basin distribution in the survey area,a 1∶200000 regional gravity survey was carried out in the Hoh Xil Lake area,and data processing and comprehensive research were carried out.The results show that the correlation between gravity anomaly and elevation and show that the crust in this area tends to be isostatic,and the moho surface and terrain are roughly“mirrored”.Twenty-one faults are identified,the Moho surface in the north of the southern fault of east Kunlun is rising rapidly,which is the boundary between the Xiyu plate and the South China plate.The location of the middle fault of east Kunlun is 12 km north of the previous location.Ten intrusive rocks are delineated,which are mainly distributed in the middle suture zone of East Kunlun.Nine meso-Cenozoic sedimentary basins are delineated,and the depth of the bottom interface is inverted,the Cenozoic thinkness of Chumaer basin is more than 2000 meters.Under the constraints of velocity structure and electrical structure,the profile geological geophysical model is established by gravity 2.5-dimensional inversion,the geological characteristics of the main structural units are analyzed,and four mineralization prospect areas are preliminarily divided.

关 键 词：可可西里湖地区 区域重力调查 断裂构造 沉积盆地 地质剖面模型 

分 类 号：P631.1[天文地球—地质矿产勘探]