Ecological evolution across the Permian/Triassic boundary at the Kangjiaping Section in Cili County, Hunan Province, China  

作　　者：WANG QinXian TONG JinNan SONG HaiJun YANG Hao 

机构地区：[1]Key Laboratory of Biogeology and Environmental Geology of Ministry of Education,China University of Geosciences,Wuhan 430074,China

出　　处：《Science China Earth Sciences》2009年第6期797-806,共10页中国科学（地球科学英文版）

基　　金：National Natural Science Foundation of China (Grant Nos. 40830212, 40621002, 40730209);National Basic Research Program of China (Grant No. 2006CB80640)

摘　　要：The stratigraphic sequence of calcimicrobialite facies at the Permian-Triassic (P/Tr) boundary has well recorded the biotic and environmental transition across the end-Permian catastrophic events. The biostratigraphy, microfacies, carbon isotopes, and fossil records across the P/Tr boundary have been studied at the Kangjiaping Section in Cili County, Hunan Province. Three biostratigraphic zones, Palaeofusulina-Colaniella Zone, Hindeodus parvus Zone, and Isarcicella staeschei Zone, are identified. The excursion of δ13Ccarb exhibits a sharp negative shift in the calcimicrobialite at the P/Tr boundary, which is roughly accordant with the abrupt bioclastic decline. In addition, five types of microfacies are recognized, including algal-foraminifer bioclastic limestone, algal-laminated calcimicrobial limestone, oolitic grainstone, vermiculate limestone, and intraclastic wackstone. The results indicate that the changeover of ecosystem from metazoan reef to calcimicrobialite in Cili is a classic case of marine ecological evolution during the Paleozoic-Mesozoic transition.The stratigraphic sequence of calcimicrobialite facies at the Permian-Triassic (P/Tr) boundary has well recorded the biotic and environmental transition across the end-Permian catastrophic events. The biostratigraphy, microfacies, carbon isotopes, and fossil records across the P/Tr boundary have been studied at the Kangjiaping Section in Cili County, Hunan Province. Three biostratigraphic zones, Palaeofusulina-Colaniella Zone, Hindeodus parvus Zone, and Isarcicella staeschei Zone, are identified. The excursion of δ13Ccarb exhibits a sharp negative shift in the calcimicrobialite at the P/Tr boundary, which is roughly accordant with the abrupt bioclastic decline. In addition, five types of microfacies are recognized, including algal-foraminifer bioclastic limestone, algal-laminated calcimicrobial limestone, oolitic grainstone, vermiculate limestone, and intraclastic wackstone. The results indicate that the changeover of ecosystem from metazoan reef to calcimicrobialite in Cili is a classic case of marine ecological evolution during the Paleozoic-Mesozoic transition.

关 键 词：PERMIAN-TRIASSIC boundary calcimicrobialite carbon isotope MICROFACIES ecosystem EVOLUTION CILI HUNAN 

分 类 号：P534.51[天文地球—古生物学与地层学]