地质学报2017，Vol.91Issue(4)：812-821,10.
西藏班戈县扎穷地区古生界混杂岩块中发现中生代化石
Mesozoic Fossils Discovered In the Paleozoic Melange at the Zhaqiong Area of Bange County, Tibet
摘要
Abstract
Ten genus eleven species Late Jurassic corals,three genus three species Early Cretaceous corals,andfive genus eight species Early Cretaceous gastropods were newly discovered in the north of the Zhaqiongarea,Xinji township,Bange county Tibet.These Late Jurassic corals are Stylina ? sp.,Goniocoraannulata Roniewicz,Epistreptophyllum cf.cornutiformis (Gregory),Solenocoenia ? sp.,Calamophylliopsis moreauana (Michelin),Thamnasteria ? sp.,Clausastraea ? sp.,Isastraea ? sp.,Montlivaltia ? sp.,Montlivaltia tenuilamellata Roniewicz、Thecosmilia ? sp.The Early Cretaceous coralsare Eoh ydnophora tosaensis Yabe & Equchi,Clausastraea tabulate Morycowa,and Stylosmilia baojiensissp.nov..The Early Cretaceous gastropods are Mesoglauconia neumayri (Nagao),Rhabdocolpusasiaticum Djalilov,Pseudomesalia bangoinensis Yu,Mesoglauconia bicarinata (Hamlin)、Mesoglauconiaarkelli Mennessier,Nerinea domaensis Yu,Mesoglauconia cf.arkelli Mennessie,Microschiza cf.inflata Orbigny.The corals indicate that the fossil-bearing strata are not Middle Permian as thoughtpreviously.These gastropods indicate that the fossil-bearing strata are not early Carboniferous as thoughtpreviously.Based on ayalysis above,the middle Devonian Xiala Fm.can be revised into Early JurassicTukari Fm.and Late Cretaceous Langshan Fm.,and Late Carboniferous Yongzhu Fm.into EarlyCretaceous Duoni Fm.Significance of the revisions of the stratigraphic age is as follows.① Thedistribution of the Upper Jurassic Tukari Fm.can reach southward to the Zhaqiong area,further denyingthe understanding of that the southern Gangdise was oldland during late Jurassic.② The recent discoveryof Early Cretaceous carbonate-facies Langshan Fm.and the shale-facies Duoni Fm.shows that the EarlyCretaceous marine strata extend southwards into the Zhaqiong area,arising doubts to the understanding ofthat the southern Gangdise was oldland or island arc during Early Cretaceous.③ No tectonic mélange wasfound to occur in Paleozoic rock and Middle Jurassic ophiloite at the Zhaqiong area,indicating no intensivetectonic activities.Thus,no large-sized outcropping and mixing mélange accumulation were produced inthe Paleozoic rocks.④ It was found that the Upper Jurassic Tukari Fm.,the Lower Cretaceous DuoniFm.and Langshan Fm.in the studied area have not experienced strong tectonic destruction;therefore,the Cuoqing basin is of good potential of oil and gas prospect.关键词
西藏/冈底斯古陆/珊瑚/腹足类/晚侏罗世/早白垩世/吐卡日组/多尼组Key words
Tibet/Gangdise Oldland/Corals/Gastropods/Late Jurassic/Early Cretaceous/Tukari Formation/Duoni Formation引用本文复制引用
孟亚洲,纪占胜,姚建新,武桂春,孙倩,廖卫华,潘华璋..西藏班戈县扎穷地区古生界混杂岩块中发现中生代化石[J].地质学报,2017,91(4):812-821,10.基金项目
本文为国家自然科学基金项目(编号41472030) （编号41472030）
科技基础性工作专项(编号2015FY310100) （编号2015FY310100）
中国地质调查局项目(编号12120115069001、1212011120142、1211402108021-2、121201102000150010-02、121201102000150010-04、1212011120115) （编号12120115069001、1212011120142、1211402108021-2、121201102000150010-02、121201102000150010-04、1212011120115）
中国地质科学院地质研究所基本科研业务费项目(编号J1313)和中国地质科学院基本科研业务费项目(J1607). （编号J1313）
