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根据钻井资料、地层剖面资料,利用Surfer8.0软件编制出晚三叠世前陆盆地各组段的残留地层等厚图,得出各组段残留地层的沉积总量,并计算出各阶段沉积通量:21.4t/(m2·Ma)、184.2t/(m2·Ma)、278.0t/(m2·Ma)、147.6t/(m2·Ma)、703.5t/(m2·Ma)、272.0t/(m2·Ma)。然后,利用物质平衡法将沉积物回剥至龙门山造山带并进行脱压校正,计算出晚三叠世龙门山造山带剥蚀总厚度为2514m,各阶段造山带剥蚀速率分别为:0.009mm/a、0.114mm/a、0.133mm/a、0.094mm/a、0.423mm/a和0.133mm/a。最终,重塑了龙门山造山带晚三叠世的隆升历史:在距今228.0～199.6Ma的时间内龙门山造山带地壳隆升了约4.3～4.6km,地表隆升了1.8～2.1km;并且隆升过程具有明显的阶段性,可划分为初始隆升(228.0～216.5Ma)、加速隆升(216.5～211.0Ma)、缓慢隆升(211.0～203.6Ma)、急剧隆升(203.6～202.7Ma)和缓慢隆升(202.7～199.6Ma)五个阶段。
According to the drilling data and stratigraphic profile data, the contour maps of residual stratigraphy in each section of the Late Triassic foreland basin were prepared by using Surfer 8.0 software, and the total sedimentary volume of the remaining strata in each section was calculated and the sedimentation of each stage was calculated Fluxes: 21.4t / (m2 · Ma), 184.2t / (m2 · Ma), 278.0t / (m2 · Ma), 147.6t / (m2 · Ma), 703.5t / (m2 · Ma) / (m2 · Ma). Then, using the material balance method, the sediments were stripped back to the Longmenshan orogenic belt and corrected for the release pressure. The total thickness of the Longmenshan orogenic belt in the Late Triassic was calculated to be 2514m. The orogenic rates at different stages were 0.009mm / a, 0.114 mm / a, 0.133 mm / a, 0.094 mm / a, 0.423 mm / a and 0.133 mm / a. In the end, the uplift of the Late Triassic uplift of the Longmenshan orogenic belt was remolded: the crust of the Longmenshan orogenic belt rose about 4.3 ~ 4.6 km within 228.0 ~ 199.6 Ma and the surface was uplifted by 1.8 ~ 2.1 km ; And the uplifting process has obvious stages and can be divided into initial uplifts (228.0-216.5Ma), accelerated uplifts (216.5-211.0Ma), slow uplifts (211.0-203.6Ma), sharp uplifts (203.6 ~ 202.7Ma) and slow uplift (202.7 ~ 199.6Ma) five stages.