REU: Paleocirculation of the Deep North Atlantic

本研究将对北大西洋西缘等高线的高分辨率快速沉积速率记录进行研究，以揭示更新世北大西洋深水（NADW）形成速率和西界潜流（WBUC）强度的变化。布雷克外脊（BOR）是北大西洋西部最大的轮廓岩漂移区，其深度为2000 ~ 4900 m。它的脊峰包含一个放大的高分辨率WBUC信号。先前资助的WBUC试点研究已经完成，并确定了BOR岩心中存在高分辨率记录。通过对岩心顶部进行稳定同位素和沉积学分析，以及计划在BOR上进行REU巡航期间回收的3个活塞岩心和9个盒状岩心，为扩大试点研究提供了资金。将岩心资料与沉积物结构、海底照片和水文图以及地震回波特征进行比较，可以获得影响沉积物物理性质因素的新信息。研究完成后，开辟了古海洋学古海流研究的新途径。

The study will examine high resolution, rapid sedimentation rate record of contourites along western margin of North Atlantic in order to decipher the changes in the rate of formation of North Atlantic deep water (NADW) and the intensity of western boundary undercurrent (WBUC) during the Pleistocene. Blake Outer Ridge (BOR), which is the largest contourite drift in western North Atlantic and extends form 2000 to 4900 m depth, is the target study area. Its ridge crest contains an amplified high resolution signal of WBUC. Previously funded pilot study on WBUC was completed and the presence of a high resolution record in BOR cores was identified. Funding is provided to expand on the pilot study through stable-isotopic and sedimentological analyses of core tops and 3 piston cores and 9 box cores planned to be retrieved during an REU cruise on BOR. A comparison of the core data with sediment structures, seafloor photos and hydrographic maps, as well as seismic echo character will yield new information about the factors influencing physical properties of sediments. When completed the study open line of paleocurrent investigations in paleoceanography.