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沉积的气候记录极其罕见，这些沉积沉积含有来自科学钻探的未改变的碳酸盐丰富的微化石。深海碳酸盐微体化石是古海洋学研究的主要目标。例如，它们含有的化合物可以在千年到数百万年的时间尺度上重建过去的全球气温变化、极地冰盖变化和全球碳循环动力学。为了能够正确地从微观化石壳中读取过去的气候信息，它们的初始地球化学成分必须保持不变。通过科学的大洋钻探从晚白垩世恢复仍然软质的富含碳酸盐的泥浆的一个突出例子是海洋钻探计划198至沙茨基隆起，这是太平洋中西部的一个中等规模的火山高原。在几个钻探地点发现了跨越马斯特里赫期至寒武纪(66~84 Ma)的碳酸盐软泥。几项使用这种材料的古海洋学研究揭示了晚白垩世温室条件下气候和生物群的发展。然而，关于过去6600万年来最先进的新生代古气候重建，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力学。最近，通过从沙茨基隆起的软沉积物中建立新的复合钻探记录和稳定同位素地层学，这一前沿被时光倒退到7200万年前。该项目的目标是利用沙茨基隆起上钻探的沉积物，开发一份完整的坎帕尼亚纪(72 Ma至84 Ma)的综合记录，从而将这一前沿进一步推向更远的时间。综合记录将根据沙茨基隆起所有可用岩心产生的X射线荧光岩心扫描数据的相关性确定。此外，新的复合体将产生大量稳定的碳和氧同位素记录，为坎帕尼亚期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制定一项国际科学钻探探险计划做出贡献，该计划的目的是在沙茨基隆起恢复新钻探地点的松散沉积物，以填补现有空白，并将整个沉积序列的恢复范围扩大到晚白垩世。