In2Cretaceous – evaluating the potential of equatorial Pacific Shatsky Rise sedimentary deposits for extending high resolution paleoceanographic reconstructions from the Maastrichtian into the Campanian (72 to 84 million years before present)

In2Cretaceous â 评估赤道太平洋沙茨基隆起沉积矿床将高分辨率古海洋重建从马斯特里赫特阶延伸到坎帕阶（距今 72 至 8400 万年）的潜力

• 批准号: 527513149
• 负责人: Dr. Thomas Westerhold
• 金额: --
• 依托单位: Zentrum für Marine Umweltwissenschaften (MARUM)
• 依托单位国家: 德国
• 项目类别: Infrastructure Priority Programmes
• 资助国家: 德国
• 项目状态: 未结题
• 来源: https://gepris.dfg.de/gepris/projekt/527513149?language=en
• 关键词: In2Cretaceous; evaluating; potential; equatorial; Pacific

Climate records from Late Cretaceous unconsolidated sedimentary deposits containing unaltered carbonate rich microfossils from scientific ocean drilling are extremely rare. Carbonate microfossil rich deposits from the deep sea floor are the prime target of paleoceanographic research. They harbor compounds that allow, for example, to reconstruct past global temperature changes, polar ice sheet variations and global carbon cycle dynamics on time scales of thousand to millions of years. To be able to correctly read past climate information out of the microscopic fossil shells, their initial geochemical composition must be retained unaltered. One outstanding example for the recovery of still soft carbonate rich mud from the Late Cretaceous by scientific ocean drilling is the Ocean Drilling Program (ODP) Expedition 198 to Shatsky Rise, a medium-sized volcanic plateau in the west-central Pacific. At several drill sites carbonate ooze was recovered spanning Maastrichtian to Campanian age (66 to 84 Ma). Several paleoceanographic studies using this material revealed important insight to the development of climate and biota during Late Cretaceous greenhouse conditions. However, with respect to state-of-the-art paleoclimatic reconstructions from the Cenozoic, the last 66 million years, studies of the Late Cretaceous lack resolution and completeness to rigorously read past climate dynamics. Recently, this frontier was moved back in time to 72 million years by establishing a new composite drill record and stable isotope stratigraphy from soft sediments of Shatsky Rise. The objectives of this project are to push this frontier even further back in time by developing a complete composite record for the Campanian, 72 to 84 Ma, using sediment deposits drilled on the Shatsky Rise. The composite record will be defined based on the correlation of X-ray fluorescence core scanning data generated from all available cores from Shatsky Rise. Additionally, a bulk stable carbon and oxygen isotope record will be generated from the new composite to establish a global geochronological reference for the Campanian Stage to guide future paleoceanographic research. The second goal of the project is to contribute to the development of an international scientific drilling expedition proposal to Shatsky Rise to recover unconsolidated sediments at new drill sites to cover existing gaps and expand the recovery of complete sedimentary sequences deep into the Late Cretaceous.

来自晚白垩世松散沉积矿床的气候记录极其罕见，其中含有来自科学海洋钻探的未改变的富含碳酸盐的微化石。深海海底富含碳酸盐微化石的沉积物是古海洋学研究的主要目标。例如，它们含有的化合物可以重建过去的全球温度变化、极地冰盖变化和数千到数百万年时间尺度的全球碳循环动态。 为了能够从微观化石壳中正确读取过去的气候信息，它们最初的地球化学成分必须保持不变。通过科学海洋钻探从白垩纪晚期回收仍然松软且富含碳酸盐的泥浆的一个突出例子是对沙茨基隆起（中西部太平洋中型火山高原）进行的海洋钻探计划 (ODP) 198 号探险。在几个钻探地点发现了从马斯特里赫特阶到坎帕阶阶（66 至 84 Ma）的碳酸盐软泥。使用这种材料进行的几项古海洋学研究揭示了白垩纪晚期温室条件下气候和生物群发展的重要见解。然而，就新生代（过去 6600 万年）最先进的古气候重建而言，晚白垩世的研究缺乏分辨率和完整性来严格解读过去的气候动态。最近，通过建立新的复合钻探记录和沙茨基隆起软沉积物的稳定同位素地层学，这一前沿被拉回了 7200 万年前。该项目的目标是利用在沙茨基隆起钻探的沉积物，开发坎帕阶 (72 至 84 Ma) 的完整综合记录，从而将这一前沿时间推得更远。综合记录将根据从 Shatsky Rise 所有可用岩心生成的 X 射线荧光岩心扫描数据的相关性来定义。此外，新的复合材料还将生成大量稳定的碳和氧同位素记录，为坎帕阶阶段建立全球地质年代学参考，以指导未来的古海洋学研究。该项目的第二个目标是为沙茨基隆起国际科学钻探探险提案的制定做出贡献，以在新钻探地点恢复松散的沉积物，以弥补现有的差距，并扩大对晚白垩世深处完整沉积序列的恢复。