黔东北石阡香树园剖面“龙马溪组”灰岩中的生物多样性  

BIODIVERSITY OF THE “LUNGMACHI FORMATION”LIMESTONES AT THE XIANGSHUYUAN SECTION,SHIQIAN,NE GUIZHOU PROVINCE,SW CHINA

作　　者：倪超[1,2] 李越[1] 邓小杰 

机构地区：[1]中国科学院南京地质古生物研究所,南京210008 [2]中国科学院大学,北京100049 [3]贵州省地质调查研究院,贵阳550004

出　　处：《微体古生物学报》2015年第1期105-113,共9页Acta Micropalaeontologica Sinica

基　　金：国家科技重大专项"大型油气田及煤层气开发"专题(2011ZX05008-001-B0);国家自然科学基金(批准号:41072002);国家基金委创新研究群体项目(批准号:41221001);国家基金委重大项目第一课题(批准号:41290260)的支持

摘　　要：黔东北石阡香树园剖面志留系底部的"龙马溪组"沉积于上扬子区黔中古陆近岸浅海带,与其它远岸相的龙马溪组下部的黑色笔石页岩差异很大,厚度仅3.3m,为黄色、黄绿色含粉砂质页岩夹6个灰岩薄层或透镜体。从灰岩中识别出叠层石、海绵、床板珊瑚、四射珊瑚、三叶虫、介形类、腕足类和棘皮类等化石碎片类型,指示了奥陶纪末赫南特冰期结束后,适宜于各类底栖生物生长的生态条件在近岸区最早出现。Sedimentary setting of the Rhuddanian（basal Silurian）＂Lungmachi Formation＂at the Xiangshuyuan section,Shiqian,NE Guizhou Province,SW China was a near-shoal belt closed to the Qianzhong Oldland.Such a palaeogeographical setting results in a quite lithological difference to the typical graptolitic black shales of the Lungmachi Formation elsewhere of the out-shelves on the Upper Yangtze Platform.The formation is 3.3mthick yellow and yellowish-green silty shales intercalated with six thin-bedded and lenses of bioclastic limestones.Bioclastic components yielded from these limestones are recognized as stromatolite,sponge spicule,tabulate and rugose corals,trilobite,ostracode,brachiopod and crinoid.Such a biotic structure implies that an idealized ecological condition for inhabitation of diverse biota was existed in the near-shoal belt aftermath the glacial event of the Hirnantian（latest Ordovician）.

关 键 词：生物多样性 “龙马溪组” 志留系底部 石阡 黔东北 

分 类 号：Q16[生物学—普通生物学]