High-Resolution Paleoenvironmental Study of the Cariaco Basin, Venezuela: Late Quaternary to Present

高积累率，缺乏生物扰动， 丰富的独特的laminae（可能是varves）， 硅质和钙质微体化石的保存， Cariaco盆地的缺氧沉积物最适合用于 建立高分辨率的古气候变化记录。 在现场项目中，活塞式、重力式和箱式岩心样品 将收集这些层状沉积物。AMS放射性碳 将使用时间控制和多个古环境代用指标 重点关注信风强度和水文平衡的变化 在过去的一年里， 冰川终止、全新世和小冰期。 对现有数据的初步分析表明， 规模很大，与全球气候变化有关。 在测试了沉积物纹层的年度性质后， 直接从沉积物中提取的代用数据的校准时间序列 将根据观测到的水文和气候数据。 天气分析和气候模式试验将用于 了解低纬度变化的重建模式， 全球变化的背景下，并测试假设的原因， 这种可变性。

High accumulation rates, the lack of bioturbation, an abundance of distinct laminae (probably varves), and the preservation of both siliceous and calcareous microfossils, make the anoxic sediments of the Cariaco Basin optimal for use in constructing high-resolution records of paleoclimatic change. During the field program, piston, gravity, and box core samples of these laminated sediments will be collected. AMS radiocarbon time control and multiple paleoenvironmental proxies will be used to focus on changes in trade wind strength and hydrologic balance over the western tropical North Atlantic region during the last glacial termination, the Holocene, and the Little Ice Age. Preliminary analysis of existing data suggests that this change was large and related to global climatic change. After testing the annual nature of the sediment laminae, calibration time series of proxy data from the sediment directly against observed hydrographic and climatic data will be made. Synoptic analysis and climate model experiments will be used to understand reconstructed patterns of low latitude variability in the context of global change and to test hypothesized causes of this variability.