The impact of the Miocene Carbonate Crash in the Atlantic and Pacific: Evidence from carbonate budgets and silt grain size studies

大西洋和太平洋中新世碳酸盐崩塌的影响：来自碳酸盐预算和淤泥粒度研究的证据

• 批准号: 13122863
• 负责人: Professor Dr. Rüdiger Henrich
• 金额: --
• 依托单位: Fachbereich 05: Geowissenschaften
• 依托单位国家: 德国
• 项目类别: Infrastructure Priority Programmes
• 财政年份: 2005
• 资助国家: 德国
• 起止时间: 2004-12-31 至 2009-12-31
• 项目状态: 已结题
• 来源: https://gepris.dfg.de/gepris/projekt/13122863?language=en
• 关键词: impact; Miocene; Carbonate; Crash; Atlantic

In the current project causes, development, evolution and termination of the Middle to Late Miocene carbonate crash events in the Atlantic and Pacific will be studied comparatively. Different hypothesis to explain these events were postulated, e.g. (1) changes in deep water circulation connected with the Initiation and/or strengthening of NADW formation and subsequent shifts in its production modes, (2) changes in overall terrigenous sediment supply to the ocean caused by the uplift of high mountain ranges and the development of huge river drainage Systems, (3) perturbations of the oceanic carbonate System induced by the Initiation of the continental margin upwelling Systems and the resultant expansion of deserts on the African continent, and (4) changes in the ecologic conditions and/or the evolution of the phytoand Zooplankton during the Middle Miocene to Pliocene that were responsible for shifts in the carbonate concentrations and for variable contributions of coccoliths and planktic foraminifers. To test these different hypothesis of potential causes we study carbonate and terrigenous flux rates and determine carbonate preservation and paleo-bottom current intensities along depth traverses at Cearä Rise and compare the results with records from other key locations in the Atlantic and Pacific.

本项目将对大西洋和太平洋中、晚中新世碳酸盐碰撞事件的成因、发展、演化和终止进行对比研究。对这些事件的解释提出了不同的假设，例如(1)与NADW形成的启动和/或加强及其随后生产方式的转变有关的深水环流的变化，(2)由于高山山脉的抬升和巨大的河流排水系统的发展而引起的对海洋的总体陆源沉积物供应的变化，(3)大陆边缘上涌系统的启动和由此导致的非洲大陆沙漠的扩张对海洋碳酸盐体系的扰动，(4)中中新世至上新世生态条件的变化和浮游植物和浮游动物的演化，导致碳酸盐浓度的变化，以及球虫和浮游有孔虫的不同贡献。为了检验这些不同的潜在成因假说，我们研究了碳酸盐和陆源通量速率，确定了沿塞拉隆起深度导线的碳酸盐保存和古海底流强度，并将结果与大西洋和太平洋其他关键地点的记录进行了比较。