Evolution of the 1.8–1.6 Ga Yanliao and Xiong’er Basins, North China Craton

Sedimentary records of the North China Craton (NCC) between 1.8-0.8 Ga are indispensable for studying the evolution of the Earth's surface ecosystem in the middle Proterozoic. Continuous late Paleoproterozoic successions (1.8-1.6 Ga) were found in the Xiong'er and Yanliao basins, which are located in the southern and northern margins of present NCC. The formation and evolution of these two basins were likely related to the breakup of Columbia supercontinent. With the deepening of research in recent years, the rifting and filling processes of these two basins are getting increasing attentions and controversies. Among them, a crucial controversy is the distribution of isochronous strata in these two basins, which is related to whether these two basins have ever been connected. In this study, we scrutinized the Paleoproterozoic successions in the Taihang Mountain area, which is located in the junction of the Xiong'er and Yanliao basins. The sedimentary distributions and overlaps indicated gradually transgression and northward extension of the Xiong'er Basin during 1.75-1.65 Ga, and demonstrated a temporary connection of the Xiong'er and Yanliao basins, at least during 1.67-1.64 Ga. We further estimated the maximum depositional ranges of the isochronous stratigraphic units and drew the evolutionary history of the Xiong'er and Yanliao basins in 1.8-1.6 Ga. These results will be helpful in further understanding the habitats of early life and predicting the distribution of mineral-containing sediments, such as iron ore and source rocks.