Discussions on the relationship between the Middle-Late Triassic sedimentary evolution and the early Indosinian Jinzi movement along the Yangtze River area in Anhui

The Palaozoic and Mesozoic strata are well developed and the geological structures are highly deformed along the Yangtze River area in Anhui. It is widely accepted that there occurred the Nanxiang movement during the late Indosinian, but whether or not the Jinzi movement existed during the early Indosinian is an open question. On the basis of key boundaries, breccias origin and sedimentary facies and palaeogeographic analysis, the authors in the present paper contend that the Jinzi movement took place indeed during the early Indosinian, and is manifested in the structural boundary between the Zhouchongcun Formation and Huangmaqing Formation with a parallel unconformity or slightly angular unconformity. The tectonic patterns are dominated by tectonic uplifting, and the basin boundary is embodied by board folds and deformational processes. Together with the Nanxiang movement, a large-scale folding and mountain building movement, the Jinzi movement has controlled the formation and development of the tectonic framework of the Yangtze River area in Anhui.