余干逆冲推覆构造基本特征及意义  

The characteristics and prospecting significance of Yugan thrust nappe structure

作　　者：刘杨 吴富江 方俊华 余江 LIU Yang;WU Fujiang;FANG Junhua;YU Jiang(Basic Geological Survey Institute of Jiangxi Geological Survey Institute,Nanchang 330030,Jiangxi,China)

机构地区：[1]江西省地质调查勘查院基础地质调查所,江西南昌330030

出　　处：《矿产与地质》2021年第6期1111-1115,共5页Mineral Resources and Geology

基　　金：中国地质调查局“江西1∶5万余干县幅、江埠幅、古楼埠幅、社赓幅区域地质调查(1212010610607)”资助。

摘　　要：通过1∶5万地质填图及部分钻孔验证,属于九岭逆冲推覆构造前峰带的余干逆冲推覆构造,由新元古界双桥山群构成的推覆岩片(块)从NW向南东越过鄱阳湖后在余干一带呈叠瓦状堆垛,形成一系列飞来峰或构造窗构造,而且在飞来峰内有构造窗、构造窗上又有飞来峰,这种“峰”内见“窗”、“窗”上叠“峰”的复杂结构样式是十分少见的。因九岭逆冲推覆构造远距离推覆作用,其前峰带推覆岩席(体)越过鄱阳湖到达了余干一带,证实了九岭逆冲推覆构造最少推移了200 km。在推覆岩席之下潜伏有大面积的晚古生代煤系地层和三叠纪煤系地层,具有较大找煤潜力。The result of 1∶50000 geological mapping survey and drilling verification shows that the Yugan thrust nappe structure is one part of the frontal zone of the Jiuling thrust nappe.The overlying rock slices(blocks)formed by the Neoproterozoic Shuangqiaoshan Group cross Poyang Lake from NW to SE,and then pile up like imbricate stackings in the Yugan area,forming a series of klippes and tectonic windows.For a rare complex style there are the tectonic windows inside the klippes and the klippes over tectonic windows.Due to the long-distance overthrusting effect of the Jiuling thrust nappe structure,the frontal thrust sheets reach Yugan area across Poyang Lake.It is shown that the Jiuling thrust nappe structure thrusts at least 200 kilometers.Under the nappe rock sheet,there is a large area of late Paleozoic coal strata and Triassic strata,which have a great potential for coal prospecting.

关 键 词：逆冲推覆构造 余干地区 隐伏煤田 萍乐坳陷 

分 类 号：P547[天文地球—构造地质学] P618.11[天文地球—地质学]