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岷江流域与成都盆地之间是以岷江为联结的剥蚀-沉积体系。根据成都盆地已有的钻孔资料和原始数据,用Sufer软件制作成都盆地晚新生代等厚图,利用等厚线计算了成都盆地残留的沉积通量,并通过成都盆地的地质演化再造恢复了成都盆地潜在的沉积通量,结果表明,成都盆地潜在的沉积通量为1665km3。同时,采用了输沙量、宇宙核素、数字高程模型、河流下切速率和裂变径迹等方法分别计算了岷江上游流域的剥蚀速率、剥蚀厚度和剥蚀量,结果表明,岷江流域的剥蚀速率应介于0.26~0.5mm/a之间,剥蚀厚度介于0.94~1.44km之间,剥蚀量介于21213.50~32636.16km3之间。在此基础上,我们对成都盆地沉积通量与岷江流域的剥蚀量进行了对比分析,结果表明,在岷江上游流域与成都盆地之间的剥蚀—沉积体系中,成都盆地沉积通量与岷江流域的剥蚀量之间的比率介于5.11%~7.85%之间,成都盆地沉积通量与岷江流域剥蚀量不相匹配,成都盆地属于半封闭盆地,因此,不能利用成都盆地晚新生代以来沉积物充填体积恢复岷江上游流域的剥蚀速率、剥蚀厚度和剥蚀量。
Between the Minjiang River Basin and the Chengdu Basin, there is an erosion-deposition system with the connection of the Minjiang River. Based on the borehole data and original data from the Chengdu basin, the Late Cenozoic iso-isopach map of the Chengdu basin was generated by Sufer software. The residual sediment flux of the Chengdu basin was calculated by the isopachies and recovered through the geological evolution of the Chengdu basin Potential sediment fluxes in the Chengdu basin show that the potential sedimentation flux in the Chengdu basin is 1665 km3. At the same time, the rates of erosion, erosion thickness and denudation in the upper reaches of the Minjiang River have been calculated by using the methods of sediment transport, cosmic nuclide, digital elevation model, river sub-shear rate and fission track. The results show that the erosion rate in the Minjiang River should Between 0.26 ~ 0.5mm / a, the erosion thickness is between 0.94 ~ 1.44km, and the erosion amount is between 21213.50 ~ 32636.16km3. On this basis, we compare the sediment flux in Chengdu basin with the erosion amount in the Minjiang River basin. The results show that in the erosion-sedimentation system between the basin and the Chengdu basin, the sediment flux in the Chengdu basin is similar to that in the Minjiang River basin , The sedimentary flux in the Chengdu basin does not match with the denudation in the Minjiang River basin, and the Chengdu basin belongs to the semi-closed basin. Therefore, sediments from the Late Cenozoic in the Chengdu basin can not be used Filling volume to restore the upper reaches of the Minjiang River erosion rate, erosion thickness and erosion.