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

环南极地层学和古水深测量：基于网格的模拟的发展

• 批准号: 44931058
• 负责人: Professor Dr. Karsten Gohl
• 金额: --
• 依托单位: Sektion Geophysik
• 依托单位国家: 德国
• 项目类别: Infrastructure Priority Programmes
• 财政年份: 2007
• 资助国家: 德国
• 起止时间: 2006-12-31 至 2011-12-31
• 项目状态: 已结题
• 来源: https://gepris.dfg.de/gepris/projekt/44931058?language=en
• 关键词: Circum; Antarctic; Stratigraphy; Paleobathymetry; Development

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.

南大洋的古海洋学模型存在边界条件缺失的问题，这些边界条件准确地描述了地质时代海底表面的几何形状及其在长时间尺度上的动态。这导致在不确定的发病和古气候的德雷克通道和塔斯马尼亚门户的深水开口的后果估计。主要深海海流系统，例如南极绕极海流，通过海洋高原和洋脊等结构性障碍物的偏转的发展和影响也没有说明，因为没有重建其水深增长。由于重建不断变化的沉积物覆盖层是精确的古水深模型中最大的缺失部分，因此，在本项目中，将通过整合南极地震数据库系统的大型地震数据库、国际合作伙伴提供的数据以及现有的钻探信息，生成从大陆架到深海平原的统一的环南极数字地层网格。这个网格将被用来计算一系列的环南极古水深网格，其中最新的板块运动学模型，岩石圈沉降曲线和动力地幔地形模型。最后，将利用这一古水深网格模拟古海洋学和古气候情景，特别强调德雷克海峡和塔斯马尼亚门户的开放以及沿着大陆架、斜坡和隆起的古水流动态。