云南西部阿冷初剖面下泥盆统牙形类生物地层  

LOWER DEVONIAN CONODONT BIOSTRATIGRAPHY OF THE ALENGCHU SECTION IN WESTERN YUNNAN PROVINCE, SOUTH CHINA

作　　者：王环环 马学平[1] Ladislav SLAVíL 魏凡 张美琼[1] 吕丹 WANG Huan-huan;MA Xue-ping;SLAViK Ladislav;WEI Fan;ZHANG Mei-qiong;LU Dan(The Key Laboratory of Orogenic Belts and Crustal Evolution（MOE）,School of Earth and Space Sciences,Peking University,Beijing 100871;Institute of Geology of the Czech Academy of Sciences,Rozvojova 269,16500 Praha 6,Czech Republic;Yunnan Key Laboratory for Palaeobiology,Yunnan University,Kunming 650091;State Key Laboratory of Palaeobiology and Stratigraphy,Center for Excellence in Life and Paleoenvironment,Nanjing Institute of Geology and Palaeontology,Chinese Academy of Sciences,Nanjing 210008;Research Institute of Petroleum Exploration and Development,PetroChina,Beijing 100083)

机构地区：[1]北京大学地球与空间科学学院造山带与地壳演化教育部重点实验室,北京100871 [2]Institute of Geology of the Czech Academy of Sciences,Rozvojova 269,16500 Praha 6,Czech Republic [3]云南大学云南省古生物研究重点实验室,云南昆明650091 [4]现代古生物学和地层学国家重点实验室,中国科学院生物演化与环境卓越创新中心,中国科学院南京地质古生物研究所,江苏南京210018 [5]中国石油勘探开发研究院,

出　　处：《地层学杂志》2018年第3期288-300,共13页Journal of Stratigraphy

基　　金：国家自然科学基金项目(No.41290260)资助：The study wasalso partly supported by the Inst Geol.Research plan：RV067985831以及现代古生物学和地层学国家重点实验室(中国科学院南京地质古生物研究所)资助(课题号143111).

摘　　要：华南地区早泥盆世早—中期的地层中含有较多的碎屑岩,缺少连续的灰岩剖面及牙形类化石,因此该地区洛赫科夫阶、布拉格阶和埃姆斯阶的底界均未能以牙形类确立。滇西阿冷初剖面海相碳酸盐岩发育,具备较好的牙形类生物地层研究条件。通过对该剖面牙形类的研究,确定了志留系-泥盆系的大致界线、洛赫科夫阶-布拉格阶的界线和布拉格阶-埃姆斯阶的界线,并对剖面志留系的地层进行了初步的划分。根据现有的牙形类研究将洛赫科夫阶划分为下、中、上三部分;布拉格阶的底界以Latericriodus steinachensis eta morphotype和Pseudogondwania ethingtoni的首次出现为标志,自下而上识别出了irregularis带和kindlei-pireneae带;在华南地区首次发现了埃姆斯阶底界的标志分子Eocostapolygnathus kitabicus。据此,认为山江组下部的时代属于洛赫科夫期,中上部属于布拉格期,阿冷初组的时代为埃姆斯期,龙马溪组上部可能属文洛克统,稗子田组则为文洛克统及以上的地层。Due to the lack of continuous lower to middle Lower Devonian limestone successions, the bases of the Lochkovian, Pragian and Emsian in South China have not been defined in terms of conodont biostratigraphy. The Alengchu section in western Yunnan currently represents one of the most continuous Lochkovian to Lower Emsian limestone sequences in South China that is suitable for conodont biostratigraphic work. In this study, we have roughly defined the bases of the Lochkovian, Pragian and Emsian, and made a preliminary division of the Silurian. The Lochkovian has been divided into lower, middle and upper parts. In the Pragian the irregularis Zone is based on Pseudogondwania ethingtoni and Latericriodus steinachensis eta morphotype. The succeeding kindlei-pireneae Zone is delimited herein indirectly based on E. trilinearis and Gondwania nevadensis alpha as reference markers. Eocostapolygnathus kitabicus is reported here for the first time in South China. Study of conodont distributions shows that the lower part of the Shanjiang Formation. is Lochkovian in age; its middle and upper parts are Pragian in age; the Alengchu Formation. is earliest Emsian in age. The age of the upper Longmaxi Formation. is probably Wenlock, whereas the Baizitian Formation. corresponds to an interval from the Wenlock through the rest of the Silurian.

关 键 词：生物地层 牙形类 阿冷初组 山江组 稗子田组 下泥盆统 志留系 华南板块 

分 类 号：P534.44[天文地球—古生物学与地层学] P534.43[天文地球—地质学]