湖北保康陡山沱组磷酸盐化微体化石组合  

PHOSPHATIZED FOSSIL ASSEMBLAGE FROM THE DOUSHANTUO FORMATION IN BAOKANG, HUBEI PROVINCE

作　　者：周传明[1] 袁训来[1] 肖书海 陈哲[1] 薛耀松[1] 

机构地区：[1]中国科学院南京地质古生物研究所,南京210008 [2]Department of Geosciences,Virginia Polytechnic Institute and State University,blacksburgva24061

出　　处：《微体古生物学报》2004年第4期349-366,共18页Acta Micropalaeontologica Sinica

基　　金：国家自然科学基金 ( 4 990 2 0 0 2 );中国科学院 ( KZCX2 -116);国家重点基础研究发展规划 ( G2 0 0 0 0 7770 0 )资助

摘　　要：中国南方震旦系陡山沱组磷块岩、燧石和页岩中陆续发现的精美保存的化石生物群 ,为我们提供了一个栩栩如生的新元古代晚期生物演化的图景 ,表明多细胞真核生物在新元古代冰期之后发生了非常显著的分异。其中磷块岩化石库以生物细胞结构的完好保存而著称。继在贵州瓮安、陕西勉县茶店和江西上饶朝阳之后 ,湖北保康白竹磷矿陡山沱组磷块岩中也发现了类似的磷酸盐化化石生物群。保康化石组合中包括多细胞藻类 Wengania,Paramecia和原地保存的 Thallophyca;大型复杂疑源类 Meghystrichosphaeridium,Echinosphaeridium和目前仅在保康发现的 Bacatisphaera;球状蓝菌化石 Archaeophycus,丝状蓝菌化石 Siphonophycus和在陡山沱组磷块岩中首次发现的 Obruchevella;同时 ,内部保存不同数量小球体的球状化石在保康也大量产出。The Sinian(Ediacaran) Doushantuo Formation at Baokang, Hubei Province, was deposited in shallow-water environments to the north of the Western Hubei Platform. The Doushantuo Formation begins with dolostone which is similar to those of post-Marinoan cap carbonates. This cap-like dolostone is succeeded by black shales, argillaceous siltstones, siltstones and sandstones, with abundant phosphatic clasts, followed by banded dolomitic intraclastic and laminated phosphorites. Further upsection, the upper Doushantuo Formation consists of dolostones intercalated with shales. Phosphatized DST (Doushantuo) fossils at Baokang are similar to those at Weng'an. Filamentous and coccoidal cyanobacteria are abundant. Key algae (Wengania, Thallophyca, Paramecia), acritarchs (Meghystrichosphaeridium, Echinosphaeridium), and globular microfossils (Parapandorina, Megaclonophycus) occur in DST phosphorites at both Weng'an and Baokang. However, the acritarch Bacatisphaera occurs only at Baokang. In situ preservation of algal thalli Thallophyca has been found in laminated phosphorites at Baokang,indicating that Thallophyca was a benthic alga, and lived in subtidal photic zone.

关 键 词：陡山沱组 微体化石 生物群 真核生物 化石组合 新元古代 磷块岩 冰期 台地 扬子地台 

分 类 号：Q913[天文地球—古生物学与地层学] Q911[生物学—古生物学]