Deciphering Oligocene Climate Dynamics

破译渐新世气候动力学

• 批准号: 203165638
• 负责人: Professor Dr. Jens O. Herrle
• 金额: --
• 依托单位: Forschungseinheit Paläo-Ozeanographie
• 依托单位国家: 德国
• 项目类别: Infrastructure Priority Programmes
• 财政年份: 2011
• 资助国家: 德国
• 起止时间: 2010-12-31 至 2019-12-31
• 项目状态: 已结题
• 来源: https://gepris.dfg.de/gepris/projekt/203165638?language=en
• 关键词: Deciphering; Oligocene; Climate; Dynamics

Understanding the evolution of the Antarctic ice-sheet, as a crucial component of Earth’s climate system, is fundamental to assess and quantify changes in ocean circulation and intensity of Pacific equatorial upwelling since the initiation of Antarctic glaciation during the late Eocene (~40 Ma). Our project aims at deciphering the mode, tempo, and amplitude of Oligocene glaciation events (glaciation vs. deglaciation) of the suggested “one cold pole” world to decipher the dynamics of Oligocene climate and the impact on equatorial paleoproductivity at orbital to suborbital time-scales from the Central Eastern Pacific Ocean (CEPO). The main focus of the project will be on the environmental/climate end-member representatives, the mid Oligocene Oi-2b maximum glaciation event (~27 Ma) and the weak late Oligocene Oi-2c glaciation event (~24 Ma), using new material from IODP Expeditions 320/321 (Pacific Equatorial Age Transect). Methods will include a combined approach of benthic and planktic foraminifera oxygen and carbon isotopes and trace element geochemistry (Mg/Ca ratios) for reconstructing bottom water temperatures and for calculating ice volume and sea level changes, respectively. In addition, benthic foraminifera accumulation rates and the Δδ13C of epi- and infaunal benthic foraminifera and Δδ13C of benthic and planktic foraminifera will be used to assess the strength of the equatorial upwelling and the ocean stratification in the Pacific ocean, the largest water, heat, nutrients, and CO2 reservoir on Earth.

了解南极冰盖的演变，作为地球气候系统的一个重要组成部分，是评估和量化海洋环流和太平洋赤道上升流强度的变化，因为在始新世晚期（~40 Ma）南极冰川开始的基础。我们的项目旨在破译模式，克里思和幅度的渐新世冰川事件（冰川与冰川消退）的建议“一个冷极”的世界，以破译渐新世气候的动态和赤道古生产力的影响，从轨道到亚轨道的时间尺度从中东太平洋（CEPO）。该项目的主要重点将是环境/气候端元代表、渐新世中期Oi-2b最大冰期事件（~27 Ma）和渐新世晚期Oi-2c弱冰期事件（~24 Ma），使用来自IODP第320/321次考察（太平洋赤道年龄断面）的新材料。方法将包括海底和南极有孔虫氧和碳同位素以及微量元素地球化学（Mg/Ca比值）的综合方法，分别用于重建底层水温和计算冰量和海平面变化。此外，底栖有孔虫的积累率、表层和下层底栖有孔虫的Δδ 13 C以及底栖有孔虫和南极有孔虫的Δδ 13 C将用于评估太平洋赤道上升流和海洋分层的强度，太平洋是地球上最大的水、热、营养物和CO2库。