T117 Integrated Biostratigraphy and Chemostratigraphy Using Conodonts—North American Pander Society Annual Meeting (Posters)

Monday, 23 September 2019
9:00 AM - 6:30 PM
Hall AB, North Building

CONODONT ZONATION, MICROFACIES ANALYSIS, AND δ13CCARB EXCURSIONS ACROSS THE PERMIAN-TRIASSIC BOUNDARY IN A SHALLOW SHOAL SETTING (YANGOU, JIANGXI PROVINCE), SOUTH CHINA

Paper number: T117-6
Program: Technical Sessions
Time: 9:00 AM – 6:30 PM

Authors

Abstract

Conodont chrono-biostratigraphy is crucial for the studies on the Permian-Triassic (P-Tr) mass extinction and provides high-resolution timescale for revealing event sequences across the Permian-Triassic boundary (PTB) in South China. Growing evidence shows that various geochemical proxies and redox conditions exhibit water-depth gradients during this critical interval. When compared with well-studied deeper water facies section, conodont biostratigraphy from shallow platform facies PTB section remains poorly studied due to rarity of conodont fossils in shallower water settings. Here, we present our new conodont zonation across the PTB from a shallow ooid shoal setting, the Yangou section, which is located ~30 km northeast of Leping County, Jiangxi Province, South China, and was situated at the eastern part of the Lower Yangtze Platform during the P-Tr transition. In Yangou, a total of six types of carbonate microfacies (MF) are recognized based on field observation and detailed petrologic analysis, including: MF 1 (ooid grainstone), MF 2 (ooid-bioclast packstone), MF 3 (ooid wackestone), MF 4 (bioclast wackestone), MF 5 (bioclast-peloid micrite), and MF 6 (laminated micrite). Of these, the first two types of microfacies predominate the entire succession in Yangou, indicating a typical shallow, high-energy ooid shoal setting. Besides, five important conodont species: Hindeodus praeparvus (Kozur), H. parvus (Kozur et Pjatakova), H. typicalis (Sweet), Isarcicella lobata (Perri et Farabegoli), and I. turgita (Kozur, Mostler and Rahimi-Yazd) are also identified, and the H. praeparvus, H. parvus, and I. lobata Zones are established. These conodont zones are comparable with their counterparts from the GSSP Meishan section and those from western Paleo-Tethyan sections. Two δ13Ccarb negative shifting excursions from Yangou correlate well with the same excursions derived from the P-Tr transition in the Meishan section.

Geological Society of America Abstracts with Programs. Vol. 51, No. 5

doi: 10.1130/abs/2019AM-336492

© Copyright 2019 The Geological Society of America (GSA), all rights reserved. Permission is hereby granted to the author(s) of this abstract to reproduce and distribute it freely, for noncommercial purposes. Permission is hereby granted to any individual scientist to download a single copy of this electronic file and reproduce up to 20 paper copies for noncommercial purposes advancing science and education, including classroom use, providing all reproductions include the complete content shown here, including the author information. All other forms of reproduction and/or transmittal are prohibited without written permission from GSA Copyright Permissions.