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The Cryogenian is a critical period in the history of the Earth. It is marked by multiple extreme climate changes that caused alternating global glacial and interglacial intervals. These dramatically changed the sedimentary system, and metal ores and source rocks distributed widely during this period. Therefore, studying the Cryogenian stratigraphic framework and sedimentary basins is important to improve the stratigraphic resolution for metal mineral and hydrocarbon prospecting and exploration in China. This review paper firstly divides three tectonic‐stratigraphic regions in China in the Cryogenian, including the tectonic‐stratigraphic regions of Great South China, Xingmeng‐Tarim, and North China. Secondly, geochronologic data and geological records are combined to clearly depict the Cryogenian sedimentary sequence of continental blocks and micro‐continental blocks in different tectonic‐stratigraphic regions. The results were used to propose a new comparison scheme of stratigraphy for the Cryogenian in China. Finally, according to differences of sedimentary evolution and tectonic evolvement, sedimentary basins and their lithofacies paleogeography are identified and summarized, respectively. [ABSTRACT FROM AUTHOR]

Cenozoic climatic and environmental changes in the arid Asian interior, and their possible relations with global climatic changes and the Tibetan Plateau uplift, have been intensively investigated and debated over past decades. Here we present 40-Myr (million years)-long n-alkane records from a continuous Cenozoic sediment sequence in the Dahonggou Section, Qaidam Basin, northern Tibetan Plateau, to infer environmental changes in the northern basin. A set of n-alkane indexes, including ACL, CPI and Paq, vary substantially and consistently throughout the records, which are interpreted to reflect relative contributions from terrestrial vascular plants vs. aquatic macrophytes, and thus indicate depositional environments. ACL values vary between 21 and 30; CPI values range from 1.0 to 8.0; and Paq values change from <0.1 to 0.8 over the past 40-Myr. We have roughly identified two periods, at 25.8-21.0 Ma (million years ago) and 13.0-17.5 Ma, with higher ACL and CPI and lower Paq values indicating predominant lacustrine environments. Lower ACL and CPI values, together with higher Paq values, occurred at >25.8 Ma, 17.5-21.0 Ma, and <13.0 Ma, corresponding to alluvial fan/river deltaic deposits and shallow lacustrine settings, consistent with the observed features in sedimentological facies. The inferred Cenozoic environmental changes in the northern Qaidam Basin appear to correspond to global climatic changes. [ABSTRACT FROM AUTHOR]