Circum-Antarctic Stratigraphy and Paleobathymetry: Development of Grid-based Simulations

南大洋的古海洋学模型缺少边界条件，无法准确描述海底表面在其地质时期的几何形状及其在长时间尺度上的动态。这导致了对德雷克海峡和塔斯马尼亚门户深水开口的开始和古气候后果的不确定估计。由于缺乏对其水深增长的重建，也没有描述主要深海洋流系统，如南极极环洋流，通过海洋高原和海脊等结构性障碍的发展及其所涉偏转。由于重建不断变化的沉积物盖层是准确的古大地测量模型缺少的最大组成部分，因此，该项目将通过整合南极地震数据库系统的大型地震数据库基础和国际合作伙伴提供的数据以及可用的钻探信息，生成从大陆架到深海平原的统一的环南极数字地层网格。这一网格将被用来计算一系列环南极古大地测量网格，其中包括最新的板块运动学模型、岩石圈沉降曲线和地幔动态地形模型。最后，将使用这一古大地测量网格模拟古海洋和古气候情景，特别强调德雷克海峡和塔斯马尼亚门户的开放以及沿大陆架、斜坡和隆起的古流动力学。

Paleoceanographic models of the Southern Ocean suffer from missing boundary conditions which describe accurately the geometries of the seafloor surfaces at their geological epoch and their dynamics over long time-scales. This results in uncertain estimates of the onset and paleoclimate consequences of the deep-water openings of the Drake Passage and the Tasmanian Gateway. The development and implications for deflections of major deep-sea current systems, e.g. the Antarctic Circum-Polar Current (ACC), through structural obstacles such as oceanic plateaus and ridges is also not described due to lacking reconstructions of their bathymetric growth. As the reconstruction of the changing sediment cover is the largest missing component for accurate paleobathymetric models, a unified circum-Antarctic digital stratigraphic grid from continental shelves to the abyssal plains will be generated in this project by integrating the large seismic data basis of the Antarctic Seismic Data Library System (SDLS) and data from international cooperation partners as well as drill information where available. This grid will then be used to calculate a series of circum-Antarctic paleobathymetric grids in which newest plate-kinematic models, lithospheric subsidence curves and models of dynamic mantle topography are incorporated. Finally, paleoceanographic and paleoclimate scenarios will be simulated using this paleobathymetric grid with particular emphasis on the opening of the Drake Passage and Tasmanian Gateway and the paleo-current dynamics along the continental shelves, slopes and rises.