The Stratigraphic Consistency and Complexity of the Ediacaran Succession in the Yangtze Platform, South China: An Integrative Correlation of the Doushantuo Formation

The Ediacaran succession preserves a critical archive of sedimentary, environmental, and biological evolution prior to the Cambrian Explosion, marking a pivotal transition in Earth’s history. In particular, the Doushantuo Formation (~635–550 Ma) in South China has been the subject of intense research over the past two decades, holding great potential for defining Ediacaran stages and series and for deciphering the co-evolution of Earth’s environment and life. While extensively studied, the inter-regional correlation of the Doushantuo Formation remains contentious, primarily due to its inherent litho- and chemo-stratigraphic complexities and the scarcity of reliable geochronological and paleontological constraints. To address these issues and establish a robust regional correlation framework for the Ediacaran succession, we conducted an integrated stratigraphic study of the Doushantuo Formation, systematically examining it from local sections, through regional framework, to global constraints. At a local scale, the newly documented Baila’ao section and the ZK103 drill core, combined with the well-characterized Liulongshan section as a reference, serve as an ideal testbed for evaluating the stratigraphic correlatability of the Doushantuo Formation in northeastern Guizhou. By integrating lithostratigraphic, sequence stratigraphic, and carbon isotope chemostratigraphic data with newly obtained (546.3 ± 0.8 Ma) and previously published high-precision geochronological constraints, we have established a coherent stratigraphic framework for the Ediacaran succession in this region. At a broader regional scale, this study systematically integrates typical sections from northeastern Guizhou and the Three Gorges area, demonstrating lateral consistency and complexity in the Doushantuo Formation and the overlying succession. Consistent markers include the basal cap carbonate and its overlying black shales, as well asspecific intervals within Member IV. In contrast, the lithological associations and carbon isotope records in Members II and III display regional variability. On this basis, this study proposes a scheme for the division and regional correlation of member boundaries within the Doushantuo Formation. This scheme defines the top of the Doushantuo Formation as a diachronous surface at 556.4 Ma in northeastern Guizhou and at 550.1 Ma in the Three Gorges area, corresponding to distinct lithological transitions to the overlying Liuchapo and Dengying formations, respectively. It further constrains the age of the Wenghui and Miaohe macrofossil biotas to 556.4–550.1 Ma, thereby supporting their inter-continental correlation with the White Sea assemblage. This study provides a practical stratigraphic framework for future work and resolves several long-standing correlation debates, constituting a major step forward for Ediacaran research in South China.