A candidate of the Induan-Olenekian boundary stratotype in the Tethyan region  

作　　者：童金南 Yuri D.Zakharov Michael J.Orchard 殷鸿福 Hans J.Hansen 

机构地区：[1]Faculty of Earth Science, China University of Geosciences, Wuhan 430074, China [2]Far Eastern Geological Institute, Russian Academy of Sciences, Vladivostok 690022,Russia [3]Geological Survey of Canada, 101-605 Robson Street, Vancouver B. C., V6B 5J3, Canada [4]Geological Institute, Copenhagen University, Oster Voldgade 10, DK-1350 Copenhagen,Denmark

出　　处：《Science China Earth Sciences》2003年第11期1182-1200,共19页中国科学（地球科学英文版）

基　　金：the National Natural Science Foundation of China(Grant No.40072011);the China National Commission on Stratigraphy;the Minis try of Science and Technology,and the Chinese“973 Program”(Grant No.G2000077705).

摘　　要：The Olenekian Stage of the Lower Triassic is named from the Boreal Realm, but the stage has never been properly defined, nor has it been applied in the low-latitude Tethyan Realm, with exception of North Caucasus and Mangyshlak. This paper proposes a stratotype for the In-duan-Olenekian boundary in the low-latitude Tethyan Realm. South China is one of the main regions in the Tethyan Realm with well-developed Lower Triassic sequences and abundant fossils. According to the basic stratigraphic records and various accumulated data, we believe that the West Pingdingshan Section in Chaohu, Anhui Province is one of the best sequences to define the Induan-Olenekian boundary. The first appearance datum (FAD) of conodont Neospathodus waageni is the preferred index to define the boundary. This datum lies 26 cm below the FAD of the ammonoids Flemingites and Euflemingites, and is located slightly prior to the top of the second Triassic normal magnetozone, and the peak of the first Triassic positive excursion of carbon isotope σ13C.The Olenekian Stage of the Lower Triassic is named from the Boreal Realm, but the stage has never been properly defined, nor has it been applied in the low-latitude Tethyan Realm, with exception of North Caucasus and Mangyshlak. This paper proposes a stratotype for the In-duan-Olenekian boundary in the low-latitude Tethyan Realm. South China is one of the main re-gions in the Tethyan Realm with well-developed Lower Triassic sequences and abundant fossils. According to the basic stratigraphic records and various accumulated data, we believe that the West Pingdingshan Section in Chaohu, Anhui Province is one of the best sequences to define the Induan-Olenekian boundary. The first appearance datum (FAD) of conodont Neospathodus waageni is the preferred index to define the boundary. This datum lies 26 cm below the FAD of the ammon-oids Flemingites and Euflemingites, and is located slightly prior to the top of the second Triassic normal magnetozone, and the peak of the first Triassic positive excursion of carbon isotope d 13C.

关 键 词：proposal  GSSP  Induan-Olenekian boundary  LOWER Triassic  CHAOHU of China. 

分 类 号：P534.51[天文地球—古生物学与地层学]