Biostratigraphic and Chemostratigraphic Correlation for the Base of the Middle Ordovician between Yichang and Western Zhejiang Areas, South China

The base of the Middle Ordovician （i.e. Dapingian Stage） has been defined at the first appearance datum （FAD） of conodont Baltoniodus？ triangularis at Huanghuachang, Yichang, China,but the precise correlation of the boundary to regions of other facies remain to be resolved. Herein we review the bios...

Full description

Saved in:
Bibliographic Details
Published in:Acta geologica Sinica (Beijing) 2011-04, Vol.85 (2), p.320-329
Main Authors: ZHANG, Yuandong, MUNNECKE, Axel, CHEN, Xu, CHENG, Junfeng, LIU, Xiao
Format: Article
Language:English
Subjects:
chemostratigraphy
Graptolite biostratigraphy
Isotopes
Middle Ordovician
slope facies
South China
中国南方
中奥陶统
化学地层学
宜昌
浙江西部
生物地层学
相边界
长江三峡地区
Citations: Items that this one cites
Items that cite this one
Online Access:Get full text
Tags: Add Tag
No Tags, Be the first to tag this record!
Description
Summary:The base of the Middle Ordovician （i.e. Dapingian Stage） has been defined at the first appearance datum （FAD） of conodont Baltoniodus？ triangularis at Huanghuachang, Yichang, China,but the precise correlation of the boundary to regions of other facies remain to be resolved. Herein we review the biostratigraphy and chemostratigraphy of the Huanghuachang Global Standard Stratotype-Section and Point （GSSP） section, and present our latest stratigraphic work on the nearby Chenjiahe s ection in Yichang, and the Hengtang Quarry section, Jiangshan, Zhejiang, which is regarded as representative of slope facies. The conodont and graptolite biostratigraphy as well as chemostratigraphy of the Chenjiahe section indicate that the base of the Middle Ordovician also falls within the graptolite Azygograptus suecicus Zone, and coincides with a high or maximum δ13C value within a minor positive carbon isotope excursion, suggesting that the base boundary can be readily recognized across the entire Yangtze Gorges area. The integrated graptolite and conodont biostratigraphy and chemostratigraphy of the Hengtang section, Jiangshan, indicates that the basal boundary probably falls within the graptolite lsograptus caduceus imitatus Zone that overlies the Azygograptus suecicus Zone, and coincides with a remarkable drop of δ13C. This difference indicates that a multi-disciplinary approach is critical to identify the base boundary in those regions where the Baltoniodus ？ triangularis is absent.
ISSN:1000-9515
1755-6724
DOI:10.1111/j.1755-6724.2011.00401.x