Continental island from the Upper Silurian (Ludlow) Sino-Korean plate  

作　　者：RONG Jiayu M.E.Johnson B.G.Baarli LI Wenguo SU Wenbo WANG Jian 

机构地区：[1]Nanjing Institute of Geology and Palaeontology,Chinese Academy of Sciences,Nanjing 210008,China [2]Geosciences Department,Williams College,Williamstown,Massachusetts 01267,USA [3]Inner Mongolian Geological Survey,Hohhot 010010,China [4]Department of Geology,Chinese University of Geology,Beijing 100083,China

出　　处：《Chinese Science Bulletin》2001年第3期238-241,共4页

基　　金：This work wassupported by the National Geographic Society through its Committee for Research and Exploration (Grant No. 6326-98 to Markes E. Johnson at Williams College) ;and the Major State Basic Research Development Program of MST, China (Grant No.

摘　　要：Recent field studies on Upper Silurian stratigraphy and paleontology in the Inner Mongolia Autonomous Region (for short Inner Mongalia) near Bater Obo (=Bateaobao) resulted in the discovery of a small continental island with fossil invertebrates preserved as encrusters (stromatoporoids and corals) attached directly to a rocky shore surface and buried by silty clay mud. The Bater island (named herein) is 610 m ×200 m in size and composed of Ordovician igneous rock (diorite). Limestone strata dating from the Ludlow Epoch (about 420 Ma) surround the island and dip away from the igneous core in a radial pattern. The encrusting fossils occur on the sheltered (south and southeast) side of the island, whereas the north side was exposed to stronger wave activity based on a basal conglomerate unit composed of diorite boulders. This is the first record of an ancient island in China and the first report worldwide of stromatoporoids as members of a rocky-shore community. The island clearly shows distinct windwardRecent field studies on Upper Silurian stratigraphy and paleontology in the Inner Mongolia Autonomous Region (for short Inner Mongalia) near Bater Obo (=Bateaobao) resulted in the discovery of a small continental island with fossil invertebrates preserved as encrusters (stromatoporoids and corals) attached directly to a rocky shore surface and buried by silty clay mud. The Bater island (oamed herein) is 610 m × 200 m in size and composed of Ordovician igneous rock (diorite). Limestone strata dating from the Ludlow Epoch (about 420 Ma) surround the island and dip away from the igneous core in a radial pattern. The encrusting fossils occur on the sheltered (south and southeast) side of the island, whereas the north side was exposed to stronger wave activity based on a basal conglomerate unit composed of diorite boulders. This is the first record of an ancient island in China and the first report worldwide of stromatoporoids as members of a rocky-shore community. The island clearly shows distinct windward and leeward deposits comparable to geologically younger islands from the Mesozoic and Cenozoic outside China.

关 键 词：SILURIAN ISLAND Sino-Korean PLATE rocky shores encrusting biota 

分 类 号：P533[天文地球—古生物学与地层学]