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保存于华南新元古代晚期陡山沱组中的磷酸盐化化石被认为与后生动物起源、真核生物演化有重要联系。位于鄂西黄陵隆起北缘的樟村坪地区,是华南最重要的工业磷矿产地之一,主要磷矿层属于埃迪卡拉纪地层,却鲜有磷块岩化石报道。此次研究利用钻孔样品的大量连续切片,在陡山沱组磷矿层中发现了丰富的保存精美的微体化石,化石组合包括可能的动物胚胎化石Megasphaera inornata;大型具刺疑源类Appendisphaerasp.,Cymatiosphaeroides kullingii,Dicrospinasphaera sp.,Ericiasphaera magna,Weissiella sp.;多细胞藻类Wengania globosa,W.exquisite,Sarcinophycus papilloformis,Thallophyca sp.,以及球状丝状蓝藻化石Archaeophycus yunnanensis,Cyanonema majus,Salome nunavutensis,Obruchevella minor,Siphonophycus kestron,S.typicum,S.robustum,S.septatum。这些微体化石的发现丰富了该区磷酸盐化化石资料,同时该化石组合面貌与黔中地区陡山沱组上磷块岩“瓮安生物群”以及峡东陡山沱组典型硅化生物群都具有相似性,化石层位的探讨也为华南不同沉积相区陡山沱组的地层对比提供了新的参考依据。
Phosphatized fossils preserved in the Doushantuo Formation in the late Neoproterozoic in southern China are thought to be associated with eukaryote evolution and the origin of metazoan species. Located in the Zhangcunping area on the northern edge of the Huangling uplift in western Hubei, it is one of the most important industrial phosphate rock production sites in southern China. The major phosphate rock layers belong to the Edicacra Formation, but few phosphate rock fossils are reported. In this study, a large number of serial sections of borehole samples were used to reveal the abundance of well-preserved microfossils in the phosphate deposit of the Doushantuo Formation. The fossil assemblage includes the possible animal embryonic fossil Megasphaera inornata, the large appendisphaerasp , Cymatiosphaeroides kullingii, Dicrospinasphaera sp., Ericiasphaera magna, Weissiella sp .; multicellular algae Wengania globosa, W. exquisite, Sarcinophycus papilloformis, Thallophyca sp., And Archaeophycus yunnanensis, Cyanonema majus, Salome nunavutensis, Obruchevella minor , Siphonophycus kestron, S. typicum, S.robustum, S. septatum. The discovery of these microfossils enriches the phosphatized fossils in the area, and at the same time, the fossil assemblages are similar to those of the phosphate rock “Weng’an Biota” in the Doushantuo Formation in the Central Guizhou Province and the typical silicification of the Doushantuo Formation in the Xiaodong Formation Biota are similar, the discussion of fossil beds also provides a new reference for stratigraphic comparison of Doushantuo Formation in different sedimentary facies of South China.