布青山—巴颜喀拉地区石炭系—二叠系研究新进展  

NEW PROGRESS IN RESEARCH ON THE CARBONIFEROUS–PERMIAN STRATA IN THE BUQINGSHAN–BAYANKALA AREA

作　　者：才航加[1] 陈光庭[1] 王春涛[1] 刘建栋[1] 李五福[1] 赵忠国 曹锦山 CAI Hang Jia;CHEN Guang Ting;WANG Chun Tao;LIU Jian Dong;LI Wu Fu;ZHAO Zhong Guo;CAO Jin(Shan Key Laboratory of Geological Process and Mineral Resources for Northern Qinghai-Tibet Plateau,Qinghai Institute of Geological Survey,Xining 810012)

机构地区：[1]青海省青藏高原北部地质过程与矿产资源重点实验室,青海省地质调查院,青海西宁810012

出　　处：《地层学杂志》2024年第2期201-209,共9页Journal of Stratigraphy

基　　金：中国地质调查局项目(12120114079701)资助。

摘　　要：青海省布青山—巴颜喀拉地区石炭系—二叠系较为发育,前人将巴颜喀拉地区呈断块、透镜状镶嵌于巴颜喀拉山群中的基性火山岩—碳酸盐岩—碎屑岩组合,以及布青山地区以断层接触形式相互叠置在一起堆积形成的构造(蛇绿)混杂岩均划归布青山群。本文结合近些年在该地区开展的1/5万、1/25万区域地质调查和相关的科研成果等资料,重新厘定了布青山—巴颜喀拉地区的石炭系—二叠系,在布青山地区废除了“布青山群”,将其中的“马尔争组”修订为非常规地层——石炭系—中二叠统马尔争蛇绿混杂岩。在巴颜喀拉地区呈断块状产出的一套基性火山岩、碳酸盐岩和碎屑岩从“布青山群”中解体出来,新建了玛曲组,为典型的洋岛玄武岩—海山碳酸盐岩沉积建造。马尔争组和玛曲组的确立,表明石炭纪—中二叠世布青山—巴颜喀拉地区仍为相当规模的洋盆,该大洋为一个多岛洋,其中存在许多微板块、海山及洋岛。The Carboniferous–Permian strata are well exposed in the Buqingshan–Bayankala area in Qinghai,NW China.They were formerly grouped into the Bunqingshan Group consisting of two rock assemblages:one is composed of basic volcanic and carbonate-clastic rocks in the Bayankara Ula area with special occurrences as lenticular and faulted blocks;the other is folded and thrusted ophiolite mélanges in the Buqingshan region.In this study,Carboniferous and Permian strata in the Buqingshan–Bayankara Ula region were systematically reviewed and revised based mainly on recent 1/50000 and 1/250000 regional geological mappings.The Buqingshan Group is invalid and shall be repealed,of which the Maerzheng Formation shall be defined to the ophiolite mélange of the Carboniferous to Middle Permian in the Buqingshan area.In addition,the suit of basic volcanics,carbonates,and clastic rocks in the Bayankara Ula region was placed into the Maqu Formation that newly created,representing a typical assembly of oceanic island basalts and carbonates in oceanic island or seamount environment.The characteristics of the Maerzheng and Maqu formations indicate a relatively large ocean basin in which multiple micro-plates,seamounts,and oceanic islands,might have been developed in the Buqingshan–BayanKara Ula region from the Carboniferous to Middle Permian.

关 键 词：马尔争蛇绿混杂岩 玛曲组 布青山群 马尔争组 

分 类 号：P534.45[天文地球—古生物学与地层学] P534.46[天文地球—地质学]