Middle Permian Sedimentary Cycles and Facies Features in the Tieqiao Section in Laibin, Guangxi, South China

ABSTRACT

In the Late Paleozoic paleogeography, the Laibin area, South China, locates in the south-eastern margin of the Laibin-Heshan isolated carbonate platform. One global stratotype section for The Guadalupian–Lopingian (G/L) (The end of the Mid-Permian) transition is located in the Tieqiao section in Laibin area, which is regarded as appropriate one for the study. Based on the analysis, seven facies (open platform, restricted platform, neritic shelf, bioclastic shoal, reef, slope, and basin) are recognized in the Maokouan Formations, besides, three sequences have been identified in the Maokouan succession. They all represent a deeping-upward then shallowing-upward sedimentary cycle, and the microfacies alternation conformable marine sequences at that time, which implies consistence of sequence number recorded in the Tieqiao section were little influenced by the role of sys-depositional fault, maybe controled by the paleoceanographic condition.

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