Distinctive Features of the Meso-Neoproterozoic Biostratigraphic Framework in China

As Chinese geologists, it is a dream to establish a complete and systematic stratigraphic sequence for the Mesoproterozoic and Neoproterozoic and to make it an international stratigraphic standard. Since 1867, the term “Sinian” was first used as a geological term in 1867 to termed the “Sinian direction” (Pumpelly R., 1867); In 1882, it was adopted as a formal stratigraphic term, known as the “Sinian System” (Richthofen, von F.F., 1882). In 1922, Grabau A. W., on behalf of the Geological Society of China, defined the Sinian System. Based on this new definition by the Geological Society of China, Lee J. S., et al., 1924 published their study on the Sinian System in the Three Gorges region of China, while Kao C S et al., 1934 published their study on the Sinian System in the Jixian section of Hebei. Both sections conformed to Grabau’s definition of the Sinian System, yet they also sparked a 80-year controversy over the study of the Sinian System in China. In 2009, the author published new Proterozoic Time Scale of China. The new Proterozoic time scale of China (Table 1) highlights following stratigraphic positions: Changchengian and Jixianian, Xishanian, Yuxian and Qingbaikouan covered by the lower boundary of Nanhuan and Sinian. The new time scale would act on significant calibration for the Precambrian stratigraphic division and correlation, showing a sequence of biostratigraphy and causing significant changes in the interpretation on regional stratigraphical correlation, tectonic setting and strata bound ore deposits. According to the stratigraphic sequences, the sequence of algal fossils, macrofossils, and metazoan fossils discovered in different sections has been re-established. First, acanthomorphic acritarchs with big size with different ornaments suddenly appears in >1.6 Ga; another biological explosion of the acanthomorphic arritachs developed in Ediacaran (Sinian) just end of glaciation of the Snow Boll. Second, Macrofossils first appears in 1.6 Ga indicate that, incompany with notable climate and environmental change, the multicellular metazoans and metephytes experienced a series of important biological evolutionary incidents from the period. It is developed Zhaojiashan biota, Weng’an biota, Miaohe biota and Ediacaran fauna before Cambrian Explosion.