甘肃玉门红柳峡地区早白垩世双壳类动物群及其生物地层意义

发布时间：2018-04-19 10:07

  本文选题：早白垩世 + 甘肃玉门　； 参考：《中国地质大学(北京)》2017年硕士论文

【摘要】：玉门红柳峡地区陆相中生界发育,自下而上划分为赤金堡组、下沟组和中沟组。对这套的陆相中生界时代争议很大,具体有晚侏罗世、晚侏罗世至早白垩世、早白垩世等不同认识。本研究在玉门红柳峡地区下沟组和中沟组获得了大量保存完好的双壳类化石,为进一步确定地层时代奠定了基础。经鉴定,下沟组双壳类化石计有7属23种,包括Musculiopsis fuxinensis,M.yixianensis,M.yumenensis,M.subrotundus,M.trigonicus,M.gansuensis,Sphaerium anderssoni,S.coreanicum,S.pujiangense,S.selenginensis,S.chientaoense,S.ellipticoides,Gansuella angulate,G.xinminpuensis,G.subrotunda,Nakamuranaia chingshanensis,N.subrotunda,N.aff.chingshanensis,Arguniella lingyuanensis,A.yanshanensis,A.liaoxiensis,Inversidens wuerheensis和Unio yanbianensis。据此建立Nakamuranaia subrotunda-Musculiopsis fuxinensis组合。中沟组双壳类化石计2属4种,包括M.subrotundus,M.gansuensis,S.pujiangense和S.anderssoni。玉门红柳峡下沟组和中沟组内的双壳类化石分子可以与浙江西部、辽宁西部、黑龙江东部及韩国东南部、外贝加尔东部、日本西南部早白垩世中Aptian—早Albian期双壳类动物群形成良好对比。结合下沟组上段火山颈相火山岩锆石年龄(109±1.6Ma),基本能够确定下沟组—中沟组时代为早白垩世中Aptian期—Albian期。
[Abstract]:The continental Mesozoic is developed in Hongliuxia area of Yumen, which is divided into Chijinbao formation, Xiagou formation and Zhonggou formation from bottom to top.The continental Mesozoic epoch is controversial, including the late Jurassic, the late Jurassic to the early Cretaceous, and the early Cretaceous.In this study, a large number of well-preserved bivalve fossils were obtained in Xiagou formation and Zhonggou formation in Hongliuxia area, Yumen, which laid a foundation for further determining the stratigraphic age.缁忛壌瀹，

本文编号：1772652