The Chew Bahir Drilling Project: A Half-Million Year Climate Record from the Southern Ethiopian Rift, Crucible of Human Evolution

作为ICDP批准的古人类遗址和古湖泊钻探项目（HSPDP）的一部分，该提案寻求继续为东非更新世湖泊沉积物的分析和解释提供部分资金。该项目的目的是检索和解释跨越人类进化史和环境变化的关键间隔的长连续沉积物岩心，接近全球重要的古人类遗址。该提案的重点是HSPDP的五个选定地点之一：埃塞俄比亚南部的深沉积盆地Chew Bahir，该地区的深钻井已于2014年11月至12月成功完成。在Chew Bahir盆地西部可获得两个重叠的沉积物岩心，恢复率为> ~ 85%，初步结果表明这覆盖了最近650 ~ 950 ka的气候历史。随后在2015年4月进行的第一次实验室活动表明，沉积沉积物似乎敏感地记录了降水和蒸发的变化，以及物源、运输机制和成岩过程。在未来两年的项目中，我们建议对岩心材料进行全面的地球化学和矿物学分析，并结合卫星遥感数据的解释。这一方面可以对高分辨率地球化学扫描和测井数据进行可靠的解释，另一方面可以破译代理地层过程。在这些对地核的标准化研究的基础上，我们将能够在轨道到十年的时间尺度上重建气候变化，这使我们能够测试与人类起源有关的气候进化假设。Chew Bahir深层钻探项目的主要目标是：阐明更新世期间气候变化（这些变化的时间、性质、突发性、幅度和同步性，特别是冰期和间冰期之间的转变）在哺乳动物（包括人类类群）进化中的作用。

This proposal seeks continued funding toward partial costs for the analysis and interpretation of Pleistocene lacustrine sediments in East Africa, as part of the ICDP - approved Hominid Sites and Paleolakes Drilling Project (HSPDP). The aim of the project is to retrieve and interpret long continuous sediment cores spanning critical intervals of human evolutionary history and environmental change, close to globally-significant hominin sites. This proposal focuses on one of the five chosen sites for HSPDP: Chew Bahir, a deep sedimentary basin in southern Ethiopia, where the deep drilling has been successfully completed in Nov-Dec 2014. Two overlapping sediment cores with a >85% recovery rate could be retrieved from the western part of the Chew Bahir basin and first results suggest that this covers the last 650-950 ka of climatic history. The subsequent first laboratory campaign in April 2015, showed that the sedimentary deposits seems to have sensitively recorded both changes in precipitation and evaporation, as well as provenance, transport mechanisms and diagenetic processes. In the next two years of the project, we propose a comprehensive geochemical and mineralogical analysis of the cored material paired with the interpretation of satellite borne remote sensing data. This will allow a reliable interpretation of the high-resolution geochemical scan and logg data on the one hand and the deciphering of the proxy formation processes on the other hand. On the basis of these standardized studies of the core, we will be able to reconstruct climatic transitions on orbital to decadal time scales, which allows us to test climate-evolution hypotheses relevant to human origins. The main objectives of the Chew Bahir deep drilling project are: To illuminate the role of climate change (timing, nature, abruptness, magnitude, and synchronicity of these shifts especially the transitions between Glacial and Interglacial) in the evolution of mammalian (including hominin taxa) during the Pleistocene.