The influence of tectonic, climate and ocean circulation on sediment transport and deposition in the western South Atlantic during the past 60 mill years

过去 60 千年来构造、气候和海洋环流对南大西洋西部沉积物输运和沉积的影响

• 批准号: 243126019
• 负责人: Dr. Gabriele Uenzelmann-Neben
• 金额: --
• 依托单位: Bundesanstalt für Geowissenschaften und Rohstoffe (BGR)
• 依托单位国家: 德国
• 项目类别: Priority Programmes
• 财政年份: 2013
• 资助国家: 德国
• 起止时间: 2012-12-31 至 2018-12-31
• 项目状态: 已结题
• 来源: https://gepris.dfg.de/gepris/projekt/243126019?language=en
• 关键词: influence; tectonic; climate; ocean; circulation

Tectonic events and modifications in climate have a direct (e.g. supply of sediment via erosion, increase of primary production) and indirect (e.g. opening/closure of gateways and hence modification of oceanic circulation, feedback on climate via uplift/subsidence) influence on sediment deposition. The study of sedimentary features at the continental margin thus provides valuable information on the regional tectonic and climatic evolution. We aim at resolving modifications in climate and oceanographic circulation at the Argentine continental margin, which result from variations in both climatic (e.g. Antarctic ice sheet formation, Mid Miocene Climate Optimum MMCO, etc.) and tectonic (rise of the Andes with its feedback on climate, emplacement of the Rio Grande Rise, opening of Drake Passage, closure of Central American Seaway CAS) processes. Sedimentary material provided amongst others by the rising Andes is deposited partly in the South Atlantic basins formed on the shelf and partly directly on the slope, rise and in the deep sea, where it is picked-up by oceanic currents, which represent an important element of the global thermohaline circulation. The deposited material represents an archive of the interplay of down-slope and along-slope sediment transport. Via the analysis of seismic data we will gain information on sediment flux from the continent into the ocean and variations in the oceanic circulation allowing conclusions on modifications in climate.The project proposed here forms a strong link to proposal 'Long-term evolution of northern Argentine-Uruguay continental margin: implications on the sediment input history of Rio de la Plata River and hydrocarbon generation and leakage' by Anka et al., which will tackle questions related to onshore-offshore basin dynamics.

构造事件和气候变化对沉积物沉积有直接（例如通过侵蚀提供沉积物、增加初级生产）和间接（例如网关的打开/关闭，从而改变海洋环流、通过隆起/下沉反馈气候）影响。因此，研究大陆边缘的沉积特征可以为区域构造和气候演化提供有价值的信息。我们的目标是解决阿根廷大陆边缘气候和海洋环流的变化，这是由于两种气候的变化（例如南极冰盖形成，中新世中期气候最佳MMCO等）。和构造（安第斯山脉的上升及其对气候的反馈，格兰德河隆起的就位，德雷克通道的开放，中美洲航道CAS的关闭）过程。上升的安第斯山脉提供的沉积物部分沉积在大陆架上形成的南大西洋盆地，部分直接沉积在斜坡、隆起和深海，在那里被洋流带走，洋流是全球温盐环流的一个重要组成部分。沉积物代表了下坡和沿坡沉积物输运相互作用的档案。通过对地震数据的分析，我们将获得关于从大陆进入海洋的沉积物通量和海洋环流变化的信息，从而得出气候变化的结论。这里提出的项目与Anka等人的提案“阿根廷-乌拉圭北方大陆边缘的长期演变：对拉普拉塔河沉积物输入历史和油气生成和泄漏的影响”形成了密切的联系。这将解决与近海盆地动力学有关的问题。