Biostratigraphy and surface-water reconstruction for the Oligocene of the North Atlantic based on organic-walled dinoflagellate cysts

基于有机壁甲藻包囊的北大西洋渐新世生物地层学和地表水重建

• 批准号: 242917912
• 负责人: Professor Dr. Oliver Friedrich
• 金额: --
• 依托单位: Institut für Geowissenschaften
• 依托单位国家: 德国
• 项目类别: Infrastructure Priority Programmes
• 财政年份: 2013
• 资助国家: 德国
• 起止时间: 2012-12-31 至 2016-12-31
• 项目状态: 已结题
• 来源: https://gepris.dfg.de/gepris/projekt/242917912?language=en
• 关键词: Biostratigraphy; surface; water; reconstruction; Oligocene; Biostratigraphy; surface; water; reconstruction; Oligocene

The Oligocene epoch (33.9-23.03 Ma) represents a critical interval of the Cenozoic because it allows to study the processes underlying the transition from a world free of large-scale continental ice shields and rapid eustatic sea-level change to one dominated by these factors. To contribute to a better understanding of Oligocene climate dynamics in the higher-latitude North Atlantic, we propose a two-step approach based on the complete, magnetostratigraphically dated Oligocene sequence recovered during IODP Expedition 342 off Newfoundland using dinoflagellate cysts as biostratigraphic and paleoenvironmental indicators. While the main focus of the first project phase was on establishing the first chronostratigraphically calibrated dinocyst biostratigraphy for the Oligocene of the higher-latitude North Atlantic, the second project phase will be dedicated to elucidating surface-water conditions during key intervals of the Oligocene using dinocysts. Much of the sample processing and microscope analyses necessary for the second project phase have already been carried out. The key intervals to be studied in high (c. 15 kyr) resolution, are (i) the Eocene/Oligocene transition (34.9-33.2 Ma; comprising the paleoceanographic change connected to the onset of large-scale Antarctic glaciation), (ii) the "mid"-Oligocene (28.3-25.9 Ma; Oi-2b glacial maximum with surface-water cooling extending into the mid-latitudes), and (iii) the Oligocene/Miocene transition (23.3-22.6 Ma; Mi-1 glacial maximum). The results will be integrated with other SST data that are currently being generated within the Expedition 342 consortium. Besides providing unprecedented insights into Oligocene surface-water dynamics in the higher-latitude North Atlantic, this study will also contribute towards a better understanding of the Oligocene climate system as a whole.

渐新世时期（33.9-23.03 mA）代表了新生代的关键间隔，因为它允许研究从没有大型大陆冰盾的世界的过渡和快速的Eustatic海平面变化到以这些因素为主的过程。为了更好地了解北大西洋上层大西洋中渐新世气候动态的理解，我们提出了一种两步方法，基于在纽芬兰（Dineoflagellate）在纽芬兰（Newfoundland）附近使用dinoflagellate catsts的完整的磁层迁移，日期降级的渐新世渐新世序列，作为BioStrataTrataTs rapoStrataTratigraphicraphicraphicraphic copraphicraphic and Paleoenvrimentalmentmentalmentalmentmentalmentmentmentalmentmentalmentmentsal。尽管第一个项目阶段的主要重点是建立第一个对高纬度北大西洋渐新世渐新世渐新世的年度地层学校准的恐龙型生物地层学，但第二个项目阶段将投入使用deriocysts的关键间隔期间阐明在寡头的关键间隔期间的地表水条件。第二个项目阶段所需的许多样本处理和显微镜分析已经进行。 The key intervals to be studied in high (c. 15 kyr) resolution, are (i) the Eocene/Oligocene transition (34.9-33.2 Ma; comprising the paleoceanographic change connected to the onset of large-scale Antarctic glaciation), (ii) the "mid"-Oligocene (28.3-25.9 Ma; Oi-2b glacial maximum with surface-water cooling extending into the中纬度）和（iii）渐新世/中新世过渡（23.3-22.6 mA; mi-1冰川最大值）。结果将与当前正在Expedition 342联盟中生成的其他SST数据集成。除了提供对北大西洋上纬度较高的渐新世地面水动力学的前所未有的见解外，这项研究还将有助于更好地理解整个渐新世气候系统。