Collaborative Research: The Hominid Sites And Paleolakes Drilling Project: Acquiring a High Resolution Paleoenvironmental Context of Human Evolution

了解地球系统过程是否以及如何影响人类进化是一项挑战，引起了科学家和公众的广泛兴趣。美国核管理委员会最近的一份报告指出，对支撑人类进化的环境动力学的理解已经成熟，可以取得重大进展。这项资助汇集了具有广泛专业知识的科学家，这个团队将扩大古环境数据集，而关于环境和人类起源之间关系的假设必须建立在这些数据集的基础上。该小组将从埃塞俄比亚和肯尼亚精心挑选的五个古湖床上的长钻岩芯中回收岩芯。这些遗址覆盖了晚新近纪和第四纪的几个重要区间，靠近关键的古人类遗址，将为古人类居住的地区提供重要的新环境信息。本次申请的资金将用于支持与钻井和初始岩心描述相关的运营成本。该项目的目标是从靠近重要人类学遗址的沉积物中获得高质量的古环境数据。钻探可以从产生古人类化石的同一层收集未改变的样本，这些近乎原始的样本包含地球化学代理数据，可用于破译该地区的环境历史。研究小组将把这些岩心与附近的海洋记录、附近含有古人类和其他脊椎动物化石的露头记录联系起来，并通过使用tephras、古地磁和其他直接测年技术，将这些岩心与人工制品组合联系起来。来自远端古湖床的岩心避免了露头样品的问题，如风化、陷窝和古环境变量的不连续表达，同时允许在不同的间隔检查季节尺度的环境变异性。该项目将从埃塞俄比亚的North Awash和Chew Bahir盆地以及肯尼亚的West Turkana、Baringo和Magadi盆地的9个钻孔中收集约2400米的岩心。这些地区发现了一些世界上最重要的古人类化石和人工制品遗址，直接引发了当前关于人类进化和环境动力学的争论。所有遗址都包含了长而连续的气候记录，跨越了过去400万年的大部分时间，并且是对一系列环境强迫机制明显敏感的地区。这些岩心将是产生定量古温度、古降水和其他环境重建的理想工具，这对理解早期人类所经历的环境动力学至关重要。这些数据还将为评估非洲古气候的大尺度和中尺度模式，以及连接早期人类生存至关重要的气候、地形、水文和植被资源的模式提供强有力的经验基础。该项目包括为9名美国和非洲学生提供培训机会，包括通过亚利桑那大学的萨瓜罗项目（Saguaro Program）重点吸引美国少数族裔本科生。许多肯尼亚和埃塞俄比亚的科学家集中参与了这个项目，而且在这个项目的所有阶段将为更多的非洲青年科学家提供培训和研究机会。公众宣传活动将通过美国和非洲的三家合作博物馆开展。在过去，当地社区从科学钻探活动中受益，将钻孔套成套管，以便将其用作水井。该项目收集的岩芯样本和数据将通过国家湖泊岩芯实验室、ICDP NGDC和史密森尼人类起源数据库提供给一般科学界。钻井作业将由国际大陆钻井方案共同出资。

Understanding whether and how Earth system processes impacted human evolution is a challenge that generates broad interest among scientists and the general public. A recent NRC report noted how understanding of the environmental dynamics underpinning human evolution is ripe for major advances. This grant brings together scientists with a breadth of expertise, and this team will expand the paleoenvironmental data set upon which hypotheses about the relationship between environment and human origins must be based. The team will recover cores from long drill cores from five carefully selected ancient lake beds in Ethiopia and Kenya. These sites cover several important intervals of the late Neogene and Quaternary, close to key paleoanthropological sites, that will provide important new environmental information about the locales inhabited by ancient hominins. Funding requested here will support operational costs related to drilling and the initial core descriptions.The goal of this project is to produce high-quality paleoenvironmental data from deposits close to key anthropological sites. Drilling allows the collection of unaltered samples from the same beds producing the hominin fossils, These near-pristine samples contain geochemical proxy data that can be used to decipher the region's environmental history. The team will correlate these drill cores to nearby marine records and to nearby outcrop records containing hominin and other vertebrate fossils, and to artifact assemblages by using tephras, paleomagnetism and other direct dating techniques. Drill cores from distal ancient lake beds avoid outcrop sample problems such as weathering, lacunae, and discontinuous expression of paleoenvironmental variables, while allowing examination of seasonal-scale environmental variability in varved intervals. The project will collect ~2400m of cores from nine bore holes at the North Awash and Chew Bahir Basins in Ethiopia, and the West Turkana, Baringo and Magadi Basins in Kenya. These areas have yielded some of the most important fossil hominin and artifact sites in the world, directly stimulating much of the current debate about human evolution and environmental dynamics. All sites contain long, continuous climate records spanning much of the last 4 million years, and are areas which are demonstrably sensitive to a range of environmental forcing mechanisms. The cores will be ideal for generating quantitative paleotemperature, paleoprecipitation, and other environmental reconstructions critical for understanding the environmental dynamics that early hominins experienced. These data will also provide a strong empirical base for evaluating both large and mesoscale models of African paleoclimate, and models linking climate, orography, hydrology and vegetation resources critical for early hominin survival.The project includes training opportunities for nine American and African students, including focused outreach efforts to attract U.S. under-represented minority undergraduates through the University of Arizona's Saguaro Program. Many Kenyan and Ethiopian scientists are centrally involved in the project, and training and research opportunities will exist for more junior African scientists at all stages of the project. Public outreach activities will be carried out through three museum partners in the US and Africa. In the past, the local communities have benefited from scientific drilling activities by casing the boreholes so that they can be used as water wells.Core samples and data collected by this project will be available to the general scientific community through the National Lacustrine Core Laboratory, ICDP NGDC, and the Smithsonian's Human Origins Database. The drilling operations will be co-funded by the International Continental Drilling Programme.