Oceanographic and climate changes and the Chicxulub impact at the Cretaceous-Paleogene (K-P) boundary ODP Leg 207, Demerara Rise, Western Atlantic

从白垩纪到古近纪（约65 Ma）的过渡与突出的环境变化有关，包括全球气候波动、主要海平面变化和洪水玄武岩火山作用，以及白垩纪-古近纪（K-P）边界的希克苏鲁伯撞击事件和全球大灭绝。为了了解这些相互关联的过程和事件，本项目旨在结合近年来的K-P研究成果，采用多学科方法解读跨越K-P边界的古气候和古海洋变化。西大西洋Demerara隆起的ODP Leg 207，在三个钻探点获得了扩展的地层完整的K-P层，在了解K-P边界层的过程中占据了中心位置，因为迄今为止在低纬度地区没有很好的K-P深水记录。地球化学、矿物学和岩石磁学方法的跨学科结合将用于(i)实现连续的¿18O和¿13C化学地层学，以估计温度和环境干扰；（ii）通过矿物学和岩石磁学代用物提供古气候和古海洋变化的约束；（iii）表征撞击喷射层及其与其他K-P边界层中发现的希克苏鲁伯喷射物的相关性。

The transition from the Cretaceous to the Paleogene (about 65 Ma ago) is associated with prominent environmental changes, including global climate fluctuations, major sea-level changes, and flood basalt volcanism, as well as with the Chicxulub impact event and the global mass extinction at the Cretaceous-Paleogene (K-P) boundary. To understand these mutually interrelated processes and events, this project aims to decipher paleoclimatic and paleoceanographic changes during an extended interval across the K-P boundary by a multidisciplinary approach in the light of results from recent K-P research. The ODP Leg 207 from the Demerara Rise, western Atlantic ¿ with its expanded and stratigraphically complete K-P interval recovered at three drill sites ¿ occupies a central position for understanding the K-P boundary interval for the ¿ so far not well documented K-P deepwater record from low latitudes. An interdisciplinary combination of geochemical, mineralogical, and rock-magnetic methods will be applied for (i) achieving a continuous ¿18O and ¿13C chemostratigraphy for estimating temperatures and environmental disturbances, (ii) providing constrains on paleoclimate and paleoceanographic changes by mineralogical and rock-magnetic proxies, and (iii) characterizing the impact ejecta layer and its correlation to the Chicxulub ejecta found in other the K-P boundary layers.