西藏措勤盆地上侏罗统吐卡日组上下段的厘定及其礁灰岩发现的油气勘探意义  

Redefinition of Upper and Lower Member of the Upper Jurassic Tukari Formation and Significances on Oil-gas Exploration of Reef Limestone in the Coqen Basin, Tibet

作　　者：孙倩 纪占胜[2] 廖卫华[3] 武桂春[4] 何继富[1,2] 石秋圆 李浩 刘振宇[5] 郭安臣 侯召硕[5] 李东泽[5] 万晓樵[1] SUN Qian;JI Zhan-sheng;LIAO Wei-hua;WU Gui-chun;HE Ji-fu;SHI Qiu-yuan;LI Hao;LIU Zhen-yu;GUO An-chen;HOU Zhao-shuo;LI Dong-ze;WAN Xiao-qiao(China University of Geosciences(Beijing),Beijing 100083;Chinese Academy of Geological Sciences,Beijing 100037;Nanjing Institute of Geology and Paleontology,Chinese Academy of Sciences,Nanjing,Jiangsu 210008;Key Laboratory of Stratigraphy and Paleontology,Ministry of Land and Resources,Institute of Geology,Chinese Academy of Geological Sciences,Beijing 100037;Geological Survey Institute of Jilin Province,Changchun,Jilin 130102)

机构地区：[1]中国地质大学(北京),北京100083 [2]中国地质科学院,北京100037 [3]中国科学院南京地质古生物研究所,江苏南京210008 [4]中国地质科学院地质研究所,国土资源部地层与古生物重点实验室,北京100037 [5]吉林省地质调查院,吉林长春130102

出　　处：《地球学报》2018年第4期419-431,共13页Acta Geoscientica Sinica

基　　金：国家自然科学基金项目(编号:41472030);科技基础性工作专项(编号:2015FY310100);中国地质调查局基础性公益性矿产地质调查项目(编号:DD20160120-02;DD20160120-04;DD20160126);中国地质科学院基本科研业务费项目(编号:J1607)联合资助~~

摘　　要：西藏班戈县保吉地区各昌茶玉剖面发现晚侏罗世珊瑚化石约12属16种,分别为Calamophylliopsis?sp.,Clausastraea?sp.,Epistreptophyllum cylindratum Milaschevitsch,Epistreptophyllum sp.,Heliocoenia aff.etalloni Koby,Kobyastraea?sp.,Montlivaltia tenuilamellats Roniewicz,Montlivaltia?sp.,Myriophyllia?sp.,Pseudocoenia hexaphyllia(d’Orbigny),Pseudocoenia?sp.,Rhipidogyra?sp.,Stephanastraea?sp.,Stylina?sp.,Stylina cf.subramosa de Fromentel,Thecosmilia?sp.等。化石指示各昌茶玉剖面上部第42—80层时代为晚侏罗世牛津期—基默里奇期,表明各昌茶玉剖面地层并不属于原划的中二叠统下拉组。本文依据化石及岩性特点将其修订为上侏罗统吐卡日组。根据保吉地区的吐卡日组与上下地层的接触关系及其岩性变化可划分为上下两段地层,各昌茶玉剖面代表吐卡日组下段地层,主要为厚层碳酸盐岩夹少量泥页岩及多层礁灰岩。久朗仓剖面代表吐卡日组上段地层,为一套碳酸盐岩夹大量粗碎屑岩地层。吐卡日组下段在措勤盆地内部、班公湖—怒江缝合带内广泛分布,指示晚侏罗世措勤盆地发育大面积广阔稳定的碳酸盐岩台地,其中生物礁表明晚侏罗世碳酸盐岩台地具有优越的油气生成和储集条件。About 16 species in 12 genera of coral fossils are recognized from the Gechangchayu section in Baoji area,Bange County,Coqen Basin,Tibet.They are Calamophylliopsis?sp.,Clausastraea?sp.,Epistreptophyllum cylindratum Milaschevitsch,Epistreptophyllum sp.,Heliocoenia aff.etalloni Koby,Kobyastraea?sp.,Montlivaltia tenuilamellats Roniewicz,Montlivaltia?sp.,Myriophyllia?sp.,Pseudocoenia hexaphyllia(d’Orbigny),Pseudocoenia?sp.,Rhipidogyra?sp.,Stephanastraea?sp.,Stylina?sp.,Stylina cf.subramosa de Fromentel,Thecosmilia?sp.These corals indicate the age of the related strata to be the Late Jurassic Oxfordian-Kimmeridgian,instead of the Middle Permian.Therefore,the coral-bearing strata were revised from the Xiala Formation to the Tukari Formation.Furthermore,the Tukari Formation was divided into two members according to this study.The Gechangchayu section represents the lower member of the Tukari Formation,characterized by thick-layer carbonate rocks interlayered with fine-grained clastic rocks and reef limestone,while the Jiulangcang section represents the upper member of the Tukari Formation,characterized by carbonate rocks interlayered with thick-layer coarse clastic sediments.The lower member of the Tukari Formation is widely distributed in both the Coqen Basin and the Bangonghu-Nujiang Suture Zone,which suggests the existence of a vast carbonate platform during the Late Jurassic in these areas.The reef limestone in the lower member of the Tukari Formation indicates a superior condition for the generation and accumulation of petroleum in the Late Jurassic carbonate platform.

关 键 词：措勤盆地 上侏罗统 吐卡日组 地层厘定 油气勘探 

分 类 号：P534.52[天文地球—古生物学与地层学] TE1[天文地球—地质学]