江西彭山穹隆构造成因及地质意义  

The Formation and Geological Significance of thePengshan Dome in Jiangxi Province

作　　者：史洪峰[1] 刘明军 孙强[1] 朱延辉 张景[1] SHI Hongfeng;LIU Mingjun;SUN Qiang;ZHU Yanhui;ZHANG Jing(Nanjing Center,China Geological Survey,Nanjing 210016,China;Taishun Bureau of Natural Resources and Planning,Wenzhou 325500,China)

机构地区：[1]中国地质调查局南京地质调查中心,江苏南京210016 [2]泰顺县自然资源和规划局,浙江温州325500

出　　处：《东华理工大学学报（自然科学版）》2024年第4期301-311,共11页Journal of East China University of Technology(Natural Science)

基　　金：中国地质调查局项目(DD20221742)。

摘　　要：为探讨彭山穹隆成因及时代,在彭山地区开展了野外地质调查、构造解析和年代学等研究工作。结果表明,彭山穹隆为构造穹隆,形态为短轴背斜,其及周边存在稳定的印支期近SN向古构造应力场,伴生NNE向走滑断层,其东侧发育东倾的逆断层。切穿穹隆的断层被霏细斑岩脉贯入,霏细斑岩脉的锆石U-Pb年龄为(123.0±1.0) Ma,隐伏黑云母花岗岩的U-Pb年龄为(123.0±1.4) Ma,古应力场同期断层中断层泥的伊利石K-Ar年龄为(228.1±10.3)~(233.2±6.5) Ma,因此认为彭山穹隆形成时间为印支期或更早。To investigate the genesis and the age of the Pengshan dome,field geological surveys,structural analyses,and chronological studies were conducted in Pengshan area.The results show that the Pengshan dome is a tectonic dome with a short axis anticline in shape.There is a stable Indosinian-period paleotectonic stress field oriented nearly SN in and around the dome,associated with NNE-trending strike-slip faults,and an eastward-dipping thrust fault on its eastern side.Felsite porphyry dykes have intruded the faults which cut through the dome.The zircon U-Pb age of the felsite porphyry dykes is(123.0±1.0)Ma,the U-Pb age of the underlying rock mass is(123.0±1.4)Ma,and the illite K-Ar age of the fault gouge in the paleostress field is(228.1±10.3)~(233.2±6.5)Ma.Therefore,the formation time of the Pengshan dome is Indosinian or earlier.

关 键 词：穹隆 构造年代学 江南造山带 彭山 

分 类 号：P542[天文地球—构造地质学]