Characterizing the Composition, Flux, and Temporal Variability of Terrigenous Sources to the Cariaco Basin: Relationship to Climate Variability

描述卡里亚科盆地陆源的成分、通量和时间变化：与气候变化的关系

• 批准号: 0451775
• 负责人: Richard Murray
• 金额: --
• 依托单位: Trustees of Boston University
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2005
• 资助国家: 美国
• 起止时间: 2005-06-01 至 2011-05-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=0451775&HistoricalAwards=false
• 关键词: Characterizing; Composition; Flux; Temporal; Variability

ABSTRACTOCE-0451775Terrigenous deposition, either fluvial or aeolian, is altered by latitudinal shifts in the Intertropical Convergence Zone (ITCZ). For example, a southern shift in the ITCZ during the Northern Hemisphere winter coincides with higher aeolian inputs in response to strong easterly trade winds, whereas during the northern migration of the ITCZ in the summer, higher fluvial inputs are observed. A scientist from Boston University will carry out a geochemical study of samples recovered from a sediment trap array in the Cariaco Basin to characterize seasonal changes in the chemical composition and total flux of the terrigenous component. Material recovered in the traps over a five year period will be analyzed for major, trace and rare earth elements, as well as radiogenic isotopes. Changes in chemical composition and total flux will be assessed as a function of precipitation, wind stress, and upwelling to understand how modern processes control the terrigenous variability at the site. In addition, this PI will complement the water column work by collecting samples along the Venezuelan coastal shelf, local rivers, Aeolian samples from Barbados, and material derived from the Orinoco River to constrain possible end-member sources. In terms of broader impacts, results from this study will further our understanding of how changes in the ITCZ alters inputs of terrigenous material which in turn can provide information on global climate variations in tropical latitudes. The project utilizes samples collected as part of the CARIACO time series off the coast of Venezuela and is a collaborative effort between Venezuelan and U.S. scientist. A graduate student from Venezuela will be trained and supported as part of this study.

ABSTRACTOCE-0451775陆源沉积，无论是河流沉积还是风沉积沉积，都会因热带辐合带 (ITCZ) 的纬度变化而改变。 例如，在北半球冬季，ITCZ 向南移动时，与强烈的东信风引起的风沙输入增加同时发生，而在夏季 ITCZ 向北迁移期间，观察到河流输入增加。 波士顿大学的一名科学家将对从卡里亚科盆地沉积物捕集器阵列中回收的样品进行地球化学研究，以表征化学成分和陆源成分总通量的季节性变化。 将在五年内对陷阱中回收的材料进行主量、微量和稀土元素以及放射性同位素的分析。 将评估化学成分和总通量的变化作为降水、风应力和上升流的函数，以了解现代过程如何控制该地点的陆地变化。 此外，该 PI 将通过收集委内瑞拉沿海陆架、当地河流的样本、巴巴多斯的风沙样本以及来自奥里诺科河的材料来补充水柱工作，以限制可能的最终成员来源。 就更广泛的影响而言，这项研究的结果将进一步我们了解 ITCZ 的变化如何改变陆源物质的输入，从而提供有关热带纬度全球气候变化的信息。 该项目利用了委内瑞拉海岸附近 CARIACO 时间序列的一部分收集的样本，是委内瑞拉和美国科学家之间的合作成果。 作为这项研究的一部分，一名来自委内瑞拉的研究生将接受培训和支持。