Environmental Signal Propagation in Sediment Routing Systems across the Permo-Triassic boundary

该项目旨在开发一套新的分析和建模工具，以增进对沉积地质学中三个最具挑战性的研究问题的了解：(1)确定深部时间的环境信号；(2)重建古代沉积物路径系统的演变；(3)跨越二叠纪-三叠纪界线的气候变化对沉积物生产和向海洋的沉积物转移的影响及其对地球历史上最具破坏性的灭绝后生物恢复的影响。主流文献支持从晚二叠世到早三叠世干旱加剧的一般模式。然而，最近的文献表明，与季节性潮湿条件和更高的水量有关的泥沙通量增加，使得气候和泥沙产量的解释存在不确定性。为了应对如此巨大的挑战，该项目依赖于一套广泛的分析工具，即古气候和古构造模型，并将其应用于俄罗斯南部和中国的部分地区，那里对火山层进行的高精度TIMS测年为限制环境在时间上的变化提供了基础。古气候和古构造模型与定量物源分析、Ne宇宙成因核素、低T热年代学和泥岩中放射性同位素示踪剂143Nd/144Nd(表示为εND)和87Sr/86Sr的结合，将为将物源、剥蚀速率和沉积通量的变化与气候变化和构造活动联系起来提供基础。证明，尤其是量化沉积物通量的增加所带来的影响是重要的。首先，由于PTB是地球历史上最关键的时间间隔之一，而构造、气候和沉积物通量变化之间的相互作用目前还知之甚少。其次，增强的硅酸盐风化作用可能有效地促进了西伯利亚圈闭火山作用释放的大气二氧化碳的封存，而在风化作用没有重大变化和火山大范围脱气的情况下，硅酸盐风化作用对气候的调节可能失败。

The project aims at developing a new set of analytical and modelling tools to improve the knowledge of three of the most challenging research questions in sedimentary geology: (i) the identification of environmental signals in deep-time, (ii) the reconstruction of the evolution of ancient sediment routing systems, (iii) the effect of climate changes across the Permian-Triassic boundary on sediment production and sediment transfer to the ocean and its impact on life recovery after the most devastating extinction in the history of our planet. The mainstream literature supports a general model indicating increasing arid condition from the Late Permian to the Early Triassic. However, more recent literature indicate increasing sediment flux related to seasonal humid conditions and higher water discharge leaving uncertainty in the interpretation of climate and sediment production unsolved. To tackle such a big challenge, the project relies on an extensive set of analytical tools, paleoclimatic and paleotectonic models, to be applied on sections in Southern Russia and China where high-precision TIMS dating of volcanic layers provide the base to constrain environmental variations in time. The integration of paleoclimatic and paleotectonic models with quantitative provenance analysis, Ne cosmogenic nuclides, Low-T thermochronology, and radiogenic isotope tracers 143Nd / 144Nd (expressed as εNd) and 87Sr / 86Sr in mudstones, will provide the base to link variations in provenance, denudation rates, and sediment flux to climate change and tectonic activity. he implications from proving and especially quantifying an increase in sediment flux are important. Firstly, because the PTB is one of the most critical time intervals in Earth history, and the interplay of tectonics, climate, and changes in the sediment flux are currently poorly understood. Secondly, enhanced silicate weathering could have effectively contributed to the sequestration of atmospheric CO2 emitted by Siberian Trap volcanism instead climate regulation by silicate weathering may have failed in case of no major change in weathering and extensive volcanic degassing.