新疆塔里木板块台地和斜坡相区奥陶系牙形刺生物地层--揭示沉积间断和大坪阶地层之缺失  

ORDOVICIAN CONODONT BIOSTRATIGRAPHY IN THE PLATFORM AND SLOPE FACIES OF THE TARIM BASIN,XINJIANG:EVIDENCE FOR A SIGNIFICANT DEPOSITIONAL GAP AND THE ABSENCE OF DAPINGIAN STRATA

作　　者：王志浩[1] 张智礼 吴荣昌[1] 甄勇毅 张元动[1,4] 李慧莉 

机构地区：[1]中国科学院南京地质古生物研究所,江苏南京210008 [2]中国石油化工股份有限公司石油勘探开发研究院,北京100083 [3]Geological Survey of New South Wales,Londonderry,NSW 2753,Australia [4]中国科学院资源地层学与古地理学重点实验室,江苏南京210008

出　　处：《地层学杂志》2017年第4期357-367,共11页Journal of Stratigraphy

基　　金：国家基金委创新研究群体项目和基金项目(41521061,41672142,41290260);中国科学院国际伙伴计划(SAFEA,20140491530)资助;IGCP 653项目“奥陶纪生物大辐射的启动过程”的阶段成果

摘　　要：新疆塔里木板块台地和斜坡相区,如柯坪、巴楚和塔中井下奥陶系牙形刺序列由下而上可综合为:特马豆克阶的Variabiloconus aff.bassleri生物带,Cordylodus angulatus生物带,Chosonodina herfurthi-Rossodus manitouensis生物带,Glyptoconus quadraplicatus生物带和Tripodus proteus生物带;弗洛阶的Serratognathus diversus生物带和Serratognathoides chuxianensis-Erraticodon tarimensis生物带;达瑞威尔阶的Lenodus variabilis生物带,Yangtzeplacognathus crassus生物带,Dzikodus tablepointensis生物带,Eoplacognathus suecicus生物带和Pygodus serra生物带;桑比阶的P.anserinus-Yangtzeplacognathus jianyeensis生物带,Baltoniodus variabilis生物带和B.alobatus生物带下部,以及凯迪阶的Belodina confluens生物带,Yaoxianognathus neimengguensis生物带,Y.yaoxianensis生物带和Aphelognathus pyramidalis生物带。台地和斜坡相区普遍缺失奥陶系大坪阶的牙形刺生物带,在弗洛阶与达瑞威尔阶之间可能由于海平面的下降事件而未接受沉积。柯坪大湾沟和巴楚一间房剖面仅发育Baltoniodus alobatus生物带下部,在B.alobatus生物带与Belodina confluens生物带之间可能也有间断。Based on a restudy of the Ordovician conodont biozonation in the platform and slope facies of the Tarim Basin,Xinjiang,the Ordovician conodont biozonation in this region can be summarized in ascending order as Tremadocian：Variabiloconus aff.bassleri,Cordylodus angulatus,Chosonodina herfurthi-Rossodus manitouensis,Glyptoconus quadraplicatus and Tripodus proteus biozones;Floian：Serratognathus diversus and Serratognathoides chuxianensis-Erraticodon tarimensis biozones;Darriwilian：Lenodus variabilis,Yangtzeplacognathus crassus,Dzikodus tablepointensis,Eoplacognathus suecicus and Pygodus serra biozones;Sandbian：P.anserinus-Yangtzeplacognathus jianyeensis,Baltoniodus variabilis and B.alobatus（lower part）biozones,and Katian：Belodina confluens,Yaoxianognathus neimengguensis,Y.yaoxianensis,and Aphelognathus pyramidalis biozones.The Aurilobodus leptosomatus-Loxodus dissectus,and Tangshanodus tangshanensis biozones erected by Zhao et al.（2000）are considered to be correlated with the Lenodus variabilis Biozone of Baltoscandia.There are no confirmed record of the Baltoniodus triangularis,Paroistodus originalis,and Microzarkodina parva biozones in the platform facies of the Tarim Basin,Xinjiang,as previous reports of Baltoniodus triangularis,Paroistodus originalis,Paroistodus cf.originalis,and Microzarkodina parvain this region were based on incorrect identification.Our reassessment of the conodont successions in the region indicates a significant depositional gap from the latest Floian to early Darriwilian in the Tarim Basin.This widely distributed hiatus in both platform and slope successions might be caused primarily by a eustatic sea-level fall during this time interval.This new observation contradicts the long standing view held by most geologists in China that the deposition from the Floian to Darriwilian in the platform and slope facies of the Tarim Basin was more or less continuous.

关 键 词：生物地层 牙形刺 海平面下降 台地和斜坡相区 奥陶系 塔里木板块 新疆 

分 类 号：P534.42[天文地球—古生物学与地层学]