Evaluating the impact of the Toarcian oceanic anoxic event on neritic platform systems in NW-Africa

早白垩世以第一次中生代海洋缺氧事件（OAE）的发生为特征。这一事件（T-OAE）与早侏罗世海洋-大气系统的一次非常重要和复杂的扰动有关。在TOAE研究中，以前的重点是欧洲露头带暴露的开阔海洋环境。相比之下，来自非欧洲地区的油田和地球化学证据却少得惊人。这就形成了本文提出的项目的强烈动机，旨在评估摩洛哥高阿特拉斯盆地晚普林恩巴氏世-中托瓦世古环境扰动的影响。摩洛哥高地图集为这一目的提供了一个特殊的自然实验室。这不仅是因为与t - oae相关的盆地沉积物，还因为它们的同时期台地等效物被很好地暴露出来。在该地区，碳酸盐岩台地生态系统具有反复破坏和重新安装的特征，这可能与与T-OAE相关的环境变化有关。可容纳空间的快速生成使得盆地剖面在地层上得到了扩展，从而可以在整个托瓦西亚段以极高的时间分辨率进行采样。因此，提出了一种高分辨率，多代理方法（C， O和Sr同位素，磷，粘土矿物学）。地球化学分析将与碳酸盐台地序列的详细沉积学和古生态学评价相结合。这些工具将应用于台地序列和同期盆地序列，以表征浅海与盆地对特提斯西南边缘早侏罗世碳循环扰动的不同响应机制。

The Early Toarcian is characterized by the occurrence of the first Mesozoic Oceanic Anoxic Event (OAE). This event (T-OAE) is associated with a very significant and complex perturbation of the Early Jurassic ocean-atmosphere system. In TOAE research, much attention has previously been paid to open oceanic settings as exposed in European outcrop belts. In contrast, field and geochemical evidence from non-European areas is surprisingly scarce. This forms a strong motivation for the project proposed here, aiming to assess the impact of Late Pliensbachian – Middle Toarcian palaeoenvironmental perturbations in the High Atlas Basin of Morocco. The High Atlas of Morocco offers an exceptional natural laboratory for this purpose. This as not only T-OAE-related basinal sediments but also their coeval platform equivalents are well exposed. In this region, the carbonate platform ecosystem is marked by repeated disruption and re-installation episodes, probably linked to environmental changes associated with the T-OAE. Rapid generation of accommodation space has lead to stratigraphically expanded basinal sections allowing for sampling in an extremely high temporal resolution across the Toarcian interval. Consequently, a high-resolution, multi-proxy approach (C, O and Sr isotopes, phosphorus, clay mineralogy) is proposed. Geochemical analyses are to be coupled with a detailed sedimentological and paleo-ecological assessment of carbonate platform successions. These tools will be applied both to platform and coeval basinal successions in order to characterize the differential response mechanisms of neritic versus basinal responses to Early Jurassic carbon cycle perturbations along the southwestern Tethyan margin.