The differential tectonic uplift in the Late Indosinian resulted in the truncation of the upper strata of the Xujiahe Formation, and the erosion of the top of the Xujiahe Formation increased gradually from the southeast to the northwest. The sedimentary facies were characterized by alluvial fan, fan delta, and delta during the Late Rhaetian stage. The Anxian Movement resulted in the substantial uplift of the Longmen Mountains and vast denudation of the early deposits of the Xujiahe Formation. The fluvial and delta sedimentary system developed extensively during the Early Rhaetian, the strata continued to overlap towards the central Sichuan uplift, and the uplift zone began to accept sediments during the Middle Rhaetian. The tectonic activities in the Late Norian led to significant uplift and denudation in the central and northern sections of the Longmen Mountains, and the sedimentary environment evolved from barrier coastal shelf to fluvial and marine delta. Accompanied by re-transgression in the Early Norian period, the Xiaotangzi Formation uplifted to the central Sichuan Basin again. Strong regressions occurred during the Late Carnian, which resulted in the reduction of the sedimentary range, and the Western Sichuan Depression was dominated by the development of a barrier coastal and shelf sedimentary system. The Western Sichuan Depression was the first to receive sediments in the Early Carnian, and the Ma’antang Formation overlays the paleokarst surface of the Leikoupo Formation from west to east and south to north. The provenance system and sedimentary filling characteristics of the Upper Triassic in the study area were studied in this paper. Based on outcrops, core logging, seismic interpretation, rock thin section analysis, and other analysis results, the internal layer of the Upper Triassic in the western and central Sichuan Basin was recorrelated.
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