Quaternary Paleoclimatic Record from Tropical South America: Drilling the Salar de Uyuni, Bolivia

美国杜克大学，ATM-9809612标题：热带南美洲第四纪古气候记录：乌尤尼盐湖钻探该奖项支持一个项目，钻探乌尤尼盐湖，以恢复一个300米长的岩心，代表了大约50万年的历史。 核心将使用多代理方法进行分析，以重建高原的气候（有效湿度和温度）时间序列。 用~（14）C、Ar/Ar和U/Th法测年。 沉积学、流体包裹体岩相学、稳定同位素和元素地球化学以及古生物（硅藻）的详细研究将构成气候重建的基础。 本论文将探讨以下几个主要问题：（1）南美洲热带地区晚更新世气候变化的本质是什么？ (2)在冰川期，热带南美洲是潮湿还是干燥？ (3)陆地热带气候变化与米兰科维奇强迫一致吗？它们与高纬度变化同步吗？ 造成这些变化的气候机制是什么（例如大气水蒸气浓度的变化）？ (4)热带地区次轨道尺度气候变化的主要频率是什么？陆地热带地区的这些变化是否与高纬度地区的变化同步？ 是什么样的气候机制导致了这些古气候特征？

AbstractATM-9809612Baker, PaulDuke UniversityTitle: Quaternary Paleoclimatic Record from Tropical South America: Drilling the Salar de UyuniThis award supports a project to drill the Salar de Uyuni in order to recover a 300-meter long core, representing a history of about 0.5Myr. The core will be analyzed using a multi-proxy approach to reconstruct a climatological (effective moisture and temperature) time series of the Altiplano. Dating will be done by 14C, Ar/Ar, and U/Th methods. Detailed studies of the sedimentology, fluid inclusion petrography, stable isotopic and elemental geochemistry, and paleobiota (diatoms) will form the basis for the climatological reconstruction. The following majors questions will be addressed: (1) What was the nature of late Pleistocene climate variability in tropical South America ? (2) Was tropical South America wet or dry during glacial stages? (3) Are terrestrial tropical climate changes consistent with Milankovitch forcing and are they synchronous with high latitude changes? What climatic mechanisms (e.g. changes in the concentration of atmospheric water vapor) are responsible for these changes? (4) What are the dominant frequencies of suborbital-scale climatic changes in the tropics and are these variations in the terrestrial tropics synchronous with those at higher latitudes? What climatic mechanisms are responsible for these paleoclimatic characteristics?