The Ordovician Retroarc Foreland Basin on the Yangtze Block Linked to the Final Assemblage of Gondwana

作者：Hao Tang, Qiang Xu, Shuangjian Li, Ling Li, Xiaofang Wang, Xiucheng Tan, Jianfeng Zheng, Stephen Kershaw, Xuefei Yang · 发表于：Lithosphere · 年份：2022 · DOI：10.2113/2022/8698933 · 被引用次数：5 · 研究领域：Geological and Geochemical Analysis、Geological and Geophysical Studies、Geological formations and processes

Abstract Amalgamation of the Yangtze and Cathaysia blocks in the context of Gondwana assembly in the early Paleozoic has been addressed for decades, but the far-field effects on the Yangtze Block during the amalgamation remain unclear. In this study, we outline the sequence stratigraphic framework of the Ordovician succession in the central-upper Yangtze Block and analyze provenance records in sandstone compositions, distributions, and detritus zircon U-Pb dating. The Ordovician succession in the central-upper Yangtze Block is subdivided into six third-order sequences, which were deposited mainly in a carbonate platform with restricted sediments in Tremadocian to early Floian stages, mixed terrigenous-carbonate deposits in mid- to late Floian stages, and open circulation sediments in Dapingian to middle Katian stages. These sequences show the central-upper Yangtze Block experienced syn-tectonic deformation with northeast-trending long-wavelength uplift and depression alternatively and the depocenter shifting from the east during Tremadocian to mid-Floian stages to the southwest in late Floian to early Hirnantian stages. Provenance data indicate that detritus in the Ordovician succession was mainly from the northern India and Kangdian paleohighland to the southwest of South China Block. Incorporating the depositional and deformation variations, we propose a retroarc foreland basin that was developed on the South China Block in response to final suturing between the South China...