Reconstructing sediment load in deep-time is one of the greatest challenges in the reconstruction of ancient sediment routing systems, particularly because solid statistical models are absent and paleo-climatic, paleo-tectonic, and sedimentary constraints are lacking. This study proposes a reliable workflow for the estimation of paleo-sediment fluxes (Q_s) applying the BQART model to a case study from the SE Germanic Basin across the Middle Permian – Early Triassic interval. The input parameters of the simulations derive from: integrated plate modelling and structural kinematics; paleodrainage and paleogeographic reconstructions; global circulation models; and sandstone compositional signatures. We apply Monte Carlo simulation to overcome the input uncertainties for eight different scenarios obtained from the combination of two area estimates, two climate models, and two time resolutions. All the models are in general agreement and show changes in sediment flux (i) being steady or declining slightly through the Middle Permian, (ii) an increase of 31% at the beginning of the Late Permian (3.6–4.6 Mt yr⁻¹), (iii) and a nearly 100% rise at the onset of the Early Triassic (7.4 Mt yr⁻¹). The variation of sediment load across the PTB is coeval to the transition from meandering/sabkha to perennial braided depositional settings recorded from the well data of Obernsees-1 and Lindau-1; it results from both increased tectonism and seasonal precipitation. The Q_s estimates agree with those of modern drainages under analogous environmental conditions, highlighting the reliability of the workflow included in this study for the quantification of sediment flux in deep time. Furthermore, the results of this study provide new insights on the highly debated evolution of the continental sequences across the PTB with strong implications for both past and future paleo-environmental reconstructions.

重建深层沉积物负荷是重建古代沉积物路径系统的最大挑战之一，特别是因为缺乏可靠的统计模型，并且缺乏古气候、古构造和沉积约束。本研究提出了一个可靠的工作流程，用于估计古沉积物通量 (Q _s) 将 BQART 模型应用于来自 SE 日耳曼盆地跨越中二叠纪 – 早三叠纪间隔的案例研究。模拟的输入参数来自：集成板建模和结构运动学；古排水和古地理重建；全球流通模型；和砂岩成分特征。我们应用蒙特卡罗模拟来克服从两个区域估计、两个气候模型和两个时间分辨率的组合中获得的八种不同情景的输入不确定性。所有模型大体一致并显示沉积物通量的变化 (i) 在中二叠世期间保持稳定或略有下降，(ii) 在晚二叠世初期（3.6-4.6 Mt yr ^-1）增加 31%)、(iii) 以及在早三叠世开始时几乎 100% 的上升（7.4 Mt yr ^-1）。从 Obernsees-1 和 Lindau-1 井数据记录的从蜿蜒/sabkha 到多年生辫状沉积环境的过渡与整个 PTB 的沉积物负荷变化是同时发生的；它是由增加的构造作用和季节性降水造成的。Q _s估计值与类似环境条件下现代排水系统_的估计值一致，突出了本研究中包含的工作流程的可靠性，用于量化深层沉积物通量。此外，这项研究的结果提供了关于跨 PTB 的大陆序列演化的新见解，对过去和未来的古环境重建具有重要意义。