Rapid Carbonate Depositional Changes Following the Permian-Triassic Mass Extinction: Sedimentary Evidence from South China  

作　　者：Li Tian Jinnan Tong David Bottjer Daoliang Chu Lei Liang Huyue Song Haijun Song 

机构地区：[1]State Key Laboratory of Biogeology and Environmental Geology, China University of Geosciences [2]Department of Earth Sciences, University of Southern California

出　　处：《Journal of Earth Science》2015年第2期166-180,共15页地球科学学刊（英文版）

基　　金：supported by the "973 Program" (No. 2011CB808800);the National Natural Science Foundation of China (Nos. 41172312, 41272372, 41302010, 41402302);the State Key Laboratory of Biogeology and Environmental Geology, China University of Geosciences (No. GKZ14Y663);the "111 Project" (No. B08030)

摘　　要：Various environmental changes were associated with the Permian-Triassic mass extinction at 252.2 Ma. Diverse unusual sediments and depositional phenomena have been uncovered as responses to environmental and biotic changes. Lithological and detailed conodont biostratigraphic correlations within six Permian-Triassic boundary sections in South China indicate rapid fluctuations in carbonate deposition. Four distinct depositional phases can be recognized： （1） normal carbonate deposition on the platform and slope during the latest Permian; （2） reduced carbonate deposition at the on- set of the main extinction horizon; （3） expanded areas of carbonate deposition during the Hindeodus changxingsensis Zone to the H. parvus Zone; and （4） persistent mud-enriched carbonate deposition in the aftermath of the Permian-Triassic transition. Although availability of skeletal carbonate was significantly reduced during the mass extinction, the increase in carbonate deposition did not behave the same way. The rapid carbonate depositional changes, presented in this study, suggest that diverse environmental changes played key roles in the carbonate deposition of the Permian-Triassic mass extinction and onset of its aftermath. An overview of hypotheses to explain these changes implies enhanced terrestrial input, abnormal ocean circulation and various geobiological processes contributed to carbonate saturation fluctuations, as the sedimentary response to large volcanic eruptions.Various environmental changes were associated with the Permian-Triassic mass extinction at 252.2 Ma. Diverse unusual sediments and depositional phenomena have been uncovered as responses to environmental and biotic changes. Lithological and detailed conodont biostratigraphic correlations within six Permian-Triassic boundary sections in South China indicate rapid fluctuations in carbonate deposition. Four distinct depositional phases can be recognized： （1） normal carbonate deposition on the platform and slope during the latest Permian; （2） reduced carbonate deposition at the on- set of the main extinction horizon; （3） expanded areas of carbonate deposition during the Hindeodus changxingsensis Zone to the H. parvus Zone; and （4） persistent mud-enriched carbonate deposition in the aftermath of the Permian-Triassic transition. Although availability of skeletal carbonate was significantly reduced during the mass extinction, the increase in carbonate deposition did not behave the same way. The rapid carbonate depositional changes, presented in this study, suggest that diverse environmental changes played key roles in the carbonate deposition of the Permian-Triassic mass extinction and onset of its aftermath. An overview of hypotheses to explain these changes implies enhanced terrestrial input, abnormal ocean circulation and various geobiological processes contributed to carbonate saturation fluctuations, as the sedimentary response to large volcanic eruptions.

关 键 词：PERMIAN-TRIASSIC mass extinction CARBONATE sedimentary response environmental change. 

分 类 号：P534[天文地球—古生物学与地层学] P512.2[天文地球—地质学]