The Chew Bahir Coring Project: Climate-vegetation feedbacks during the African Humid Period in the southern Ethiopian Rift

我们建议获得多达10个重复的CA。沿沿着穿过南埃塞俄比亚裂谷Chew Bahir盆地的南北向和东西向断面的15-20米长的连续沉积物岩心。这些岩心可能包括非洲潮湿期（约15至5 kyrs BP）的沉积物，为我们提供了关于东非最后一次干湿循环和相关环境变化的信息。对这些岩心的分析将提供关于Chew Bahir沉积过程的必要信息，这是在ICDP原始人遗址和古湖泊钻探项目框架内详细规划埃塞俄比亚裂谷南部更深钻探所需的信息。第一个目标是研究盆地沉积物的类型和特征，特别是关于有机质，包括花粉和生物标志物。第二个目标是根据平行碳酸盐和木炭样品的高分辨率AMS 14 C年代学确定Chew Bahir的沉积速率及其变化，以估计可能的储层效应。第三个目标是测试有争议的讨论的假设的时间，幅度和同步性的非洲湿润期在整个大陆，包括可能的不稳定性和内部的变化，这一事件的影响，这一重要的干-湿-干转变在热带生物圈。

We propose to obtain up to ten replicate ca. 15-20 meter long continuous sediment cores along a north-south and an east-west transect through the Chew Bahir basin, Southern Ethiopian Rift These cores presumably include the deposits of the African Humid Period (~15 to 5 kyrs BP) providing us with information about the last dry-wet-dry cycle and associated environmental variations in East Africa. The analysis of these cores will provide the necessary information about sedimentary processes in the Chew Bahir as required for detailed planning of deeper drilling in the Southern Ethiopian Rift within the framework of the ICDP Hominid Sites and Paleolakes Drilling Project project. The first objective is to study the type and character of sediment in the basin, in particular with respect to the organic matter including pollen and biomarkers. The second objective is to determine the sedimentation rates and its variation in the Chew Bahir based on a high-resolution AMS 14C chronology on parallel carbonate and charcoal samples to estimate possible reservoir effects. The third objective is to test controversially-discussed hypotheses about the timing, magnitude and synchronicity of the African Humid Period across the continent including the possible abruptness and internal variability of this event and the influence of this important dry-wet-dry shift in the tropics on the biosphere.