江西南部余田群翰岗组的建立及其地质意义  

Establishment and Geological Significance of Hangang Formation in Yutian Group,Southern Jiangxi Province

作　　者：韦昌袭 巫建华[1,2] 张婧妍[2,3] WEI Chang-xi;WU Jian-hua;ZHANG Jing-yan(State Key Laboratory of Nuclear Resources and Environment,East China University of Technology, Nanchang 330013,China;School of Earth Science, East China University of Technology, Nanchang 330013,China;Jiangxi College of Applied Technology, Ganzhou 341000, China)

机构地区：[1]东华理工大学核资源与环境国家重点实验室,江西南昌330013 [2]东华理工大学地球科学学院,江西南昌330013 [3]江西应用技术职业学院,江西赣州341000

出　　处：《东华理工大学学报（自然科学版）》2019年第1期30-36,62,共8页Journal of East China University of Technology(Natural Science)

基　　金：中国核工业集团总公司项目(中核地计〔2008〕74号)

摘　　要：江西南部广泛发育早侏罗世—中侏罗世早期沉积岩系和火山岩系,前者称为林山群(划分为水北组和罗坳组),后者称为余田群(划分为水头迳组和菖蒲组),但菖蒲组之上有一套杂色沉积岩系,其岩石地层单位归属一直存在分歧。通过临江盆地临江-余田-田螺圈余田群的层型剖面、东坑盆地里仁-程口剖面和菖蒲盆地热水-黄屋剖面的系统研究,发现菖蒲组与其上的杂色沉积岩系呈整合接触,属火山旋回晚期的喷发-沉积相产物,建议称为翰岗组,并作为余田群顶部的一个岩石地层单位。新建的翰岗组,下部和上部的岩石组合特征分别与林山群水北组和罗坳组的岩石组合特征一致,指示余田群火山岩系和林山群沉积岩系属相变关系;翰岗组不含玄武岩和流纹岩,指示菖蒲组玄武岩、流纹岩形成于翰岗组之前,结合火山岩锆石U-Pb年龄和古生物资料,进一步证实菖蒲组玄武岩和流纹岩属双峰式火山岩组合;翰岗组杂色沉积岩系发育在菖蒲组火山岩之上,而白面石盆地赋存铀矿的水头迳组沉积岩系发育在菖蒲组火山岩之下,指示菖蒲、东坑和临江盆地不能参照白面石式铀矿找矿模式开展铀矿勘查工作。The sedimentary and volcanic systems of the early Jurassic-middle Jurassic were developed in the south of Jiangxi Province in the eastern part of the Nanling tectonic belt. The former is called Linshan Group and the latter is called Yutian Group. However, there is a set of mottled sedimentary rock system on the Changpu Formation, and its rock stratigraphic unit attribution has been divided. Through the systematic study of the Linjiang-Yutian-Tianluoquan’s profile in Linjiang basin, the Liren-Chengkou’s profile in Dongkeng basin and the volcanic system in the Changpu basin, it is found that there is a set of sedimentary rocks above the bimodal volcanic rocks, which are integrated contact and considered the formation of a complete volcanic cycle with the Shuitoujing Formation and the Changpu Formation, can be called Hangang Formation and placed on top of Yutian Group. The establishment of Hangang Formation in Yutian Group not only provides evidence for the zodiac variation relationship between bimodal volcanic system and Linshan Group of sedimentary rocks, but also provides new evidences for the Shuangfeng volcanic rocks of Changpu Formation, and further instructs the Changpu basin, Dongkeng basin and Linjiang basin not to carry out uranium prospecting by reference to the white stone type uranium mine.

关 键 词：余田群 翰岗组 早-中侏罗世 江西南部 

分 类 号：P588.1[天文地球—岩石学]