Multistratigraphic framework for continental Permian-Triassic boundary sections of northern Pangaea: key to a better understanding of the ecological consequences of the end-Permian crisis in the terrestrial realm

二叠纪-三叠纪界线(PTB)的全球过程造成了已知的最严重的生物多样性危机。为了了解这种大规模灭绝的触发机制，需要对海洋和陆地生态系统进行多学科研究。在海洋领域，连续的化石记录可以实现高分辨率的生物地层学，而在陆地领域，由于不连续的沉积，时间分辨率通常是有限的。因此，海洋-陆地遥相关很难探测到，因此是一个极具争议性的话题。此外，联合古陆北部的大部分陆地PT剖面的特征是在关键的PTB间隔处有一个间歇。因此，中欧、俄罗斯向斜、西伯利亚和中国北部为数不多的完整陆相PTB剖面对于破译二叠纪末期危机的触发过程至关重要。因此，该项目的目标是：a)该项目的目的是利用多地层学方法探测陆相地层中的油气田位置，并将大陆界线区段与海洋参考区段进行对比。生物地层学调查将重点放在甲壳类动物上。目前基于结核藻类的对比方案需要通过火山碎屑岩的辐射测年以及整合磁性和化学地层学(d13C-、d18O-、d34S-同位素)数据来改进和校准。B)此外，该项目的目的是详细说明生物和非生物数据，这些数据适用于描述不同大地构造和气候背景下海陆混合以及仅在大陆PTB剖面中的环境变化。重点放在孢粉相、相结构和古土壤的记录以及同位素和沉积物地球化学上。选定的界线剖面从S、中国的眉山海相层型剖面，经S中国的海陆混合剖面，到中国北部的纯大陆剖面。这些界线剖面可以通过海洋化石(牙形石、丝虫类)和来自火山碎屑岩的放射性数据进行精确对比。横断面由俄罗斯向斜的大陆PTB段延续，具有精确的四足和磁/同位素地层格架，并经匈牙利和波兰到达中欧盆地连续的PTB段。所有这些剖面都在关键的PT转变(自己的初步工作)中产生了贝壳，这将使精确的海洋-陆地对比成为可能。此外，该断面还跨越了不同的大地构造单元和不同的生物群。因此，将有可能区分区域构造和区域气候过程(古纬度的影响)和整个PTB的全球过程。所获得的数据将有助于对关于肺结核事件及其触发机制的现有假说进行批判性分析，并最终将有助于理解造成生态系统重大扰动的全球过程。

Global processes at the Permian-Triassic boundary (PTB) caused the most severe biodiversity crisis known. In order to understand the triggering mechanisms of this mass extinction, multidisciplinary research on marine and terrestrial ecosystems is required. Within the marine realm a continuous fossil record enables high-resolution biostratigraphy, whereas time resolution is usually limited in the terrestrial realm due to discontinuous sedimentation. Thus, marine-terrestrial teleconnections are difficult to detect and therefore a highly controversial topic. Additionally, the majority of terrestrial PT sections of northern Pangaea are characterized by a hiatus at the critical PTB interval. Consequently, the few complete terrestrial PTB sections of central Europe, the Russian syncline, Siberia and N China are pivotal for deciphering the triggering processes of the end-Permian crisis. Accordingly, project aims are:A) The project aims to detect the position of the PTB in continental series using a multistratigraphic approach, and to correlate continental boundary sections with marine reference sections. Biostratigraphic investigations will focus on conchostracans. The current correlation schemes based on conchostracans need to be refined and calibrated by radiometric dating of pyroclastics as well as by integrating magneto- and chemostratigraphic (d13C-, d18O-, d34S-isotope) data. B) Furthermore, the project aims to elaborate biotic and abiotic data which are suited to characterize environmental changes in mixed marine-continental as well as in exclusively continental PTB sections within different geotectonic and climatic settings. The focus is set on palynofacies, documentation of facies architectures and palaeosoils as well as on isotopic and sediment geochemistry. The selected boundary sections form a transect from the marine stratotype section in Meishan (S China) via mixed marine-continental sections in S China to pure continental sections in N China. These boundary sections can be precisely correlated by marine fossils (conodonts, fusulinids) and radiometric data from pyroclastics. The transect is continued by continental PTB sections of the Russian syncline with a precise tetrapod- and magneto-/isotope-stratigraphic framework, and via Hungary and Poland to the continuous PTB section of the Central European basin. All these sections yield conchostracans in the critical PT transition (own preliminary work) which will enable precise marine-terrestrial correlations. Furthermore, the transect crosses different geotectonic units and different biomes. Thus, it will be possible to distinguish regional tectonical and regional climatic processes (effects of palaeolatitude) from global processes across the PTB. The data obtained will enable a critical analysis of existing hypotheses on the PTB event and its triggering mechanisms and finally, will contribute to the understanding of global processes causing major perturbation of ecosystems.