Late Tremadocian(Early Ordovician) reefs on the Yangtze Platform, South China, and their geobiological implications: a synthesis  

作　　者：Jian-Po Wang Qi-Jian Li Stephen Kershaw Yuan-Yuan Zhang Shen-Yang Yu Yue Li 

机构地区：[1]Wuhan Centre of Geological Survey,China Geological Survey,Wuhan 430205,Hubei Province,China [2]Hubei Key Laboratory of Paleontology and Geological Environment Evolution,Wuhan 430205,Hubei Province,China [3]State Key Laboratory of Palaeobiology and Stratigraphy,Nanjing Institute of Geology and Palaeontology,Chinese Academy of Sciences,Nanjing 210008,Jiangsu Province,China. [4]Center for Excellence in Life and Paleoenvironment,Chinese Academy of Sciences,Nanjing 210008,Jiangsu Province,China [5]Department of Life Sciences,Halsbury Building,Brunei University,Kingston Lane,Uxbridge UB83PH,UK [6]Qufu Normal University,Shandong Province,Rizhao 276826,China

出　　处：《Journal of Palaeogeography》2021年第2期182-196,共15页古地理学报（英文版）

基　　金：supported by the China Geological Survey Project (Grant No.DD2019823);the Natural Science Foundation of China (Grant No. 41702003);the Youth Innovation Promotion Association of CAS (2019310);the special fund for strategic pilot technology Chinese Academy of Sciences(Type B, Grant No. XDB26000000)。

摘　　要：This study provides an overview and discussion of controls on the distribution of organic reefs during the Early Ordovican Period, in the Yangtze Platform, a region of epicontinental sedimentary rocks in South China. The Yangtze Platform was located in low latitudes during the Early Ordovician and recorded rich and diverse reefs through that time. During the late Tremadocian Epoch, dolomitic and stratiform stromatolites were common in supratidal to intertidal zones of the western Yangtze Platform, while columnar stromatolites formed in deeper waters of the eastern Yangtze Platform. Skeletal-dominated reefs occurred in upper subtidal settings of the central Yangtze Platform. A transition from microbial-dominated to metazoan-dominated reefs with shallowing-upward cycles was evident, indicating that the composition of the main reef-builders was driven mainly by water depth.Increasing metazoan competition during the Great Ordovician Biodiversification Event reduced the abundance of microbial reefs. Sufficient nutrient supply is interpreted to have promoted development of skeletal-dominated reefs locally in shallow settings in the central Yangtze Platform, especially represented by the expansion of abundant solitary fossils of lithistid sponges and Calathium. High salinity environmental settings facilitated the bloom of stromatolites in near-shore locations. Low oxygen content in deep subtidal settings may have led to the absence of skeletal reefs in these habitats, so the mass occurrences of stromatolites was located in the shallower-water central and eastern platform. No keratose sponge-bearing stromatolite can be confirmed across the platform during this interval.

关 键 词：Reef succession Spatial distribution Late Tremadocian Early Ordovician Yangtze Platform South China Block 

分 类 号：Q911[天文地球—古生物学与地层学]