Quantifying the bulk mineralogy of Arctic Ocean sediments of the last 80 Ma: Terrigenous sediment transport, climate and sediment deposition characteristics

该项目继续致力于北冰洋中部白垩纪至第四纪沉积物的全定量相分析。正如X射线衍射数据在岩性测定中的广泛应用所表明的那样！这是IODP 302航次-北极取芯考察（ACEX）岩心的一个重要单位，是国际协调调查第四纪至白垩纪沉积物取芯的重要组成部分。目前，230粉末样品进行了研究，X射线衍射揭示沉积和早期成岩历史的ACEX核心。该研究项目的第二年旨在对最相关的沉积物序列进行更高分辨率的采样。ACEX岩心的初始地层结果假定从大约15-16百万年前（中新世中期）到今天的连续沉积。这是第一次在北纬88°附近的记录中，以前所未有的细节，提供了解决北方半球冰川增加的变化。潜在冰川区的矿物指纹是众所周知的。因此，海冰和/或冰山的沉积物输送是可以重建的，早期冰川的历史可以清除。晚白垩世-早第三纪温室沉积序列与中第三纪冰库沉积序列之间的矿物组合变化强烈。在这里，我们将试图破译，如果只有构造的原因（分离和淹没的罗蒙诺索夫海岭幻灯片）或额外的源区变化的原因。

This project continues to aim on the full quantitative phase analysis (QPA) of Cretaceous to Quaternary sediments of the central Arctic Ocean (AO). As indicated by the extensive use of the X-ray diffraction data for the determination of lithologica! units of the IODP Leg 302-Arctic Coring Expedition (ACEX) cores it is an important part of the internationally coordinated investigation of the cored Quaternary to Cretaceous sediments. Currently, 230 powdered samples are investigated with Xray diffraction revealing the sedimentation and early diagenetic history of the ACEX cores. The second year of this research project aims on a higher resolution sampling of the most relevant sediment sequences. Initial stratigraphic results of the ACEX cores assume a continuous sedimentation from about 15-16 Mill, years ago (middle Miocene) to today. This provides for the first time the change to resolve the increasing glaciations of the Northern Hemisphere in unprecedented detail in a record from about 88° N. The mineralogical fingerprints of the potential glaciated regions are well known. As a result, sediment transport by sea ice and/ or icebergs are reconstructable and the early glaciation history can be cleared. The mineral assemblage has strongly changed between the late Cretaceous/ Early Tertiary Greenhouse and the middle Tertiary Icehouse sediment sequences. Here, we will try to decipher if only tectonic reasons (separation and drowning of the Lomonosov Ridge slide) or additionally source region change have been the reason.