Extinction pattern and process of siliceous sponge spicules in deep-water during the latest Permian in South China  

作　　者：GuiChun Liu  QingLai Feng SongZhu Gu 

机构地区：[1] Key Laboratory of Biogeology and Environmental Geology of Ministry of Education, China University of Geosciences, Wuhan, 430074, China [2] State Key Laboratory of Geological Processes and Mineral Resources, China University of Geosciences, Wuhan, 4300

出　　处：《Science China Earth Sciences》2008年第11期1623-1632,共10页中国科学（地球科学英文版）

基　　金：NSFC Innovation Research Group Program (Grant No. 40621002);MOE Innovation Research Team Program (Grant No. IRT0546);the SINOPEC Project (Grant No. G0800-06-ZS-319)

摘　　要：Diverse and abundant siliceous sponge spicules were found in the latest Permian beds, Dongpan and Ma’anying sections, South China, including 52 types and 85 forms. Further investigation on these spicules allows us to understand extinction patterns and proDiverse and abundant siliceous sponge spicules were found in the latest Permian beds, Dongpan and Ma'anying sections, South China, including 52 types and 85 forms. Further investigation on these spicules allows us to understand extinction patterns and processes of deep-water sponges. These sponge spicules rapidly decreased below the Permian/Triassic boundary (PTB), and the extinction rates reach up to 88%-90% for types and 88%-92% for forms. Their extinction pattern is a gradual one that consists of two stages: the first is characterized by a gentle and slow extinction speed and low extinction rate, and the second by sharp and fast extinction speed and high extinction rate. The morphological extinction process is involved in the disappearance first of the triaxons and tetraxons, then of the polyaxons and demas, and last of monaxons. In exterior structure extinction, the complex spicules with branches and spines became extinct more easily than did smooth spicules. After the end-Permian mass extinction, only five common and smooth forms survived: Oxeas A, Oxeas B, Strongles B, Oxy-orthpentactines and Oxy-orthohexactines A.

关 键 词：siliceous sponge SPICULES PERMIAN-TRIASSIC EXTINCTION PATTERN PROCESS South China 

分 类 号：Q915[天文地球—古生物学与地层学]