Skeleton Fossils Of Ediacaran From The Gaojiashan Biota In Ningqiang Area,Southern Shaanxi

Gaojiashan Biota is based with mineralized fossils, both with soft-bodied metazoan and macro-algae fossils. The fossils are mainly produced in the middle and upper part of Gaojiashan member, Dengying Formation in the Ediacaran, Ningqiang County of Shaanxi. under the boundary continuous sedimentary sequence of Sinian-Cambrian. the time limit is about551-541Ma. between the Ediacaran fauna and Early Cambrian small shelly fauna. Skeletal fossils with mineralized wall that in the Gaojiashan biota include tubular fossils (Cloudia&Sinotubulites), vase-shaped microfossils, as well as some other skeleton fossils. These fossils have a certain difference from the Ediacaran fauna and Early Cambrian small shelly fauna.Study with those mineralized skeletal fossils. mainly have the following understandings:(1)Make certain explain to the causes of the tube ornamentation about tubular fossil Sinotubulites. suggest that the fold-shaped morphology is resulted from deformation. rather than the inherent morphological characteristics. Summary the tube ornamentation discover there have5/6/8longitudinal ridges.and that these characteristics with the pipe body more responsive to the environment of progressive evolution in.(2)Then we have a discussion about the paleoecology of Sinotubulites. according to a variety of morphological features of the walls, as well as the bent tube growth characteristics in the original ecological conditions. we suggest that the table is a flat habitat biological. Investigative studies about the fine structure and the tube growth patterns. the wall are composed of aphanitic; tube growth patterns tend to induction mode from the outside.(3)Discovered and described a new class of Sinotubulites tube. and have a simple discussion about the species divied program. there has a misleading in species divided according to the ornamentation. but the morphological structure of the tube has a smaller affection than ornamentation during the transport and deposition. compared to the ornamentation, morphology structure of the tube in species divided is more convincing.(4)Some additional morphology aspects about Cloudina, some longitudinal omamentations that pinchout toward to the bottom of the single cone has found. these longitudinal omamentations may has a certain role in maintaining the relatively stable belong single cones. last recover its morphology structure, reproductive mode is also discussed.(5)The first time identified the occurrence of vase-shaped microfossils in the lijiagou section, expanding its geographic occurrence.(6)Found more skeleton fossils. including monomers and split spherical fossils, exotic shell fossils, biological aggregates, and trace fossils. through the comparative study of these fossils, the diversity of Precambrian life was enriched.