Chemostratigraphy and pyrite morphology across the Wuchiapingian‐Changhsingian boundary in the Middle Yangtze Platform, South China. (26th April 2021)

• Record Type: Journal Article
• Authors: Wei, Hengye; Tang, Wei; Gu, Heng; Fu, Xiugen; Zhang, Xuan
• Other Names: Chen Zhong‐Qiang guestEditor.; Wang Xiangdong guestEditor.; Cao Cangqun guestEditor.; Luo Mao guestEditor.
• Is Part Of: Geological journal. Volume 56:Number 12(2021)
• Page Start: 6102
• Page End: 6116
• Publication Date: 2021-04-26
• Subjects: carbon isotope -- carbonate‐associated‐sulphate -- euxinia -- Late Permian -- mass extinction -- pyrite framboids; Geology -- Periodicals; 551
• DOI: 10.1002/gj.4153
• Languages: English
• ISSNs: 0072-1050

Abstract

Abstract : Separated mass extinction occurred at the beginning and the ending of the Late Permian, called end‐Guadalupian and end‐Permian mass extinctions, respectively. Palaeoenvironmental changes in the middle of the Late Permian could give more insights into the environmental causes for the Permian extinctions. In this contribution, we analysed carbonate carbon isotope and carbonate‐associated‐sulphate sulphur isotope compositions to constrain the carbon and sulphur cycles across the Wuchiapingian‐Changhsingian boundary (WCB) at Yanglinqiao in Zigui in the Middle Yangtze Platform. Pyrite morphology and pyrite framboids size distribution were used to analyse redox conditions variations across the WCB. Our results show that an episodic euxinia event occurred across the WCB. This anoxic/euxinic event across the WCB was a global event, and was mainly caused by the upwelling during the cooling event. Both inorganic‐ and organic‐carbon isotopic compositions show covariance of a negative shift across the WCB at Yanglinqiao and other places in South China. This carbon‐isotopic negative excursion across the WCB was a regional carbon cycle perturbation and may be linked to the light‐carbon input from the upwelling water mass. Although the seawater δ 34 S across the WCB recorded a negative excursion in two locations in South China, it reflects the riverine input of 32 S‐enriched sulphate and represent a regional signal. These environmental anomalies such as oceanic anoxia/euxinia, global carbon cycle perturbation, cooling, end of the Emeishan large igneous province movement across the WCB may have delayed the recovery from the end‐Guadalupian mass extinction. Abstract : Together, our results show a global episodic euxinia event, a regional carbon isotope negative excursion, which was driven by upwelling, and a regional sulphate sulphur isotopic negative excursion across the Wuchiapingian‐Changhsingian boundary (WCB) in the Late Permian. These environmental deteriorations likely delay bio‐recovery from the Guadalupian biocrisis.