STRATIGRAPHY AND FOSSIL RECORD OF THE NEOPROTEROZOIC-CAMBRIAN TRANSITION ON THE NORTHERN MARGIN OF THE SOUTH CHINA PLATE (NINGQIANG, SHAANXI)

摘要

The Neoproterozoic-Cambrian transition witnessed an extraordinary biotic turnover in the evolutionary history of animals, and worldwide fossil evidence indicates that the origin and diversification of most extant metazoan phyla occurred in this interval. Late Neoproterozoic-Early Cambrian sedimentary successions ranging from shallow to deep marine environments are well developed and widely exposed on the South China (Yangtze) Plate where they have an abundant metazoan fossil record (Zhu et al., 2003). During recent decades, South China has been one of the most dynamic research regions for investigating the origin and early diversification of metazoans because of the discovery and documentation of a number of important deposits of exceptional preservation such as the Weng'an Biota from the Toushantuo (Doushantuo) Formation, the Gaojiashan Biota from the Gaojiashan Member of the Tongying (Dengying) Formation, the small shelly fossils (SSFs) and phosphatized embryos from the Meishucunian rocks, the Niutitang Biota from the Niutitang Formation, and the Chengjiang Biota from the Yu'anshan Formation. The Gaojiashan Biota and Meishucunian phosphatized embryos were mainly documented from Ningqiang County, southern Shaanxi Province, and the stratigraphic units yielding these significant fossils will be visited during this excursion.