Abstract:Since the late Permian, influenced by the Indosinian orogeny and Emeishan basalt eruption, the sediment sources and sediment patterns have changed significantly in the southwest margin of the upper Yangtze, which aroused heated discussion in academia. Therefore, in this paper, taking the detrital rocks from the Lower Triassic Feixianguan Formation in the Daibu area of Southwest Upper Yangtze as an example, constrains the source rock properties、material provenance, sedimentation and tectonic environment background by the aspects of petrography、petrogeochemical and Zircon U-Pb chronology. The maturity of the detrital rocks from the Feixianguan Formation is low, and the weathering degree of the rocks is medium, the source region has experienced continuous tectonic uplift and denudation, and deposited in the oxidative sedimentary environment of the shallow-littoral facies in the southwestern margin of the Yangtze in the Early Triassic. The U-Pb age of zircon in this paper is mainly concentrated at 257 ± 2.9ma, which is consistent with the main eruption time of Emeishan basalt in Late Permian, the petrogeochemical characteristics of the detrital rocks are highly consistentd with the Emeishan high-Ti basalt, indicating that the main source area of the Feixianguan Formation is the near-source Emeishan igneous province, the source rock is mainly the Emeishan high-Ti basalt which formed in an intraplate extensional environment, and during the basaltic magma upwelling a small amount of ancient crystalline basement components of the Yangtze block mixed in. Furtherly, the Kangdian ancient land and the Yangtze craton also provided part of the sediment sources, mainly the magmatic rocks which formed under the background of Rodinia supercontinent convergence and breakup. Chronological evidence shows that the Rodinia supercontinent convergence and breakup events have a good response to the sediment sources in the study area, which provides an important reference basis for the time constraints of global Rodinia supercontinent convergence and breakup events.