Quantifying the denudations of major tectonic events in Sichuan basin：Constrained by the paleothermal records

Abstract：Based on the paleo-thermal indicator of vitrinite reflectance (Ro), the authors reconstructed the denudation thickness of the sedimentary formation in the boreholes of Sichuan basin. The largest denudation occurred in southeastern Sichuan basin and reached 2000m in Caledonian period. During Dongwu movement, the denudation reached the values of 260~450m in southwestern Sichuan basin and reached 800~900m in southeastern Sichuan basin. Both areas were close to the central zone of Emeishan basalts. The basin was uplifted in early Indosinian period, and the denudation thickness reached 100~500m. In middle and late Indosinian period, the areas around the Longmen Mountain began to be denudated, and the denudation thickness in boreholes of these areas reached the values of over 2000m. In Yanshanian period, the areas around the mountains beside Sichuan basin experienced variable degrees of denudation due to the uplifting of these mountains. According to the inversion results of many boreholes, the maximum denudation occurred in areas close to the basin boundary and reached 2000m in Himalayan period. However, the areas which were uplifted in the early time were subjected to less denudation, and the values only reached 1000m or so.