New Stratigraphic and Archaeological Investigations on the Origin of the Acheulean at Olduvai Gorge

在美国国家科学基金会的支持下，林赛·麦克亨利博士和一个由同事组成的国际团队将在坦桑尼亚的奥杜瓦伊峡谷进行两个季节的实地地质和考古研究。该团队汇集了美国、英国、西班牙和坦桑尼亚的地质学家和考古学家，重新审视了Olduvai中上床II的经典化石和石器遗址。奥杜瓦伊的这段时间（约179万年至115万年）保存了早期人类和动物化石、石器和气候的关键变化证据，包括能人的消失、直立人的出现、原始奥杜瓦石器的终结，以及更先进的阿舍利工具的首次出现。与许多其他非洲考古遗址不同，许多奥杜瓦伊文物是在原始或接近原始的环境中发现的，为人类行为提供了额外的信息。自从40多年前dr . Leakey最初的研究以来，很少对中上部II层进行实地研究。尽管Olduvai II层很重要，但出土遗址的年龄和地层位置却很少受到限制。对II层顶部年龄的估计在140万年到100万年之间。这40万年的时间跨度使得人们无法将奥杜瓦伊的记录与东非其他可能同时期的遗址进行时间上的比较，也使得将奥杜瓦伊的大量考古数据纳入人类进化的区域研究变得困难。为了解决这个问题，本研究将使用创新的40Ar/39Ar辐射测量方法来确定II床火山灰的年代。除了为区域对比提供更好的数据外，该项目还将改善Olduvai地区的点对点对比。该项目将研究Olduvai沉积物中的火山灰，确定每种火山灰的独特成分“指纹”，并使用这些指纹来识别不同地点的单个灰烬。通过对考古遗址上方和下方灰烬的分析，本项目将构建一个新的II层地层格架。利用这个高分辨率的框架，该项目将测试聚集在古奥杜瓦伊湖边缘的“发达的奥杜瓦”考古遗址是否与更内陆的早期阿舍利共存。使用现代组合解释对人工制品进行的重新调查将有助于测试这两个组合是否实际上代表了独特的行业，或者它们是否是对不同生态环境的适应性反应。这个项目的智力价值在于为Olduvai II层建立了一个新的、经过地球化学测试的地层框架，可以测试和完善其考古遗址的相对年龄。新的日期将为这个众所周知的年代模糊的间隔提供年龄控制，并将奥杜瓦伊的记录与气候和技术变化的区域记录联系起来。对II层发育的Oldowan和Acheulean组合的重新检查将结合现场和实验室工作，为Oldowan -早期Acheulean序列最初定义的地点提供现代重新评估。这项研究更广泛的影响是，它将提高对奥杜瓦伊在人类进化、技术发展和气候变化记录中的时间和考古地位的理解。该项目将为美国、英国和坦桑尼亚的学生提供培训，并将帮助改善坦桑尼亚国家历史博物馆的古人类学设施。

With National Science Foundation support, Dr. Lindsay McHenry and an international team of colleagues will conduct two field seasons of geological and archaeological research at Olduvai Gorge, Tanzania. The team brings together U.S., U.K., Spanish, and Tanzanian geologists and archaeologists to revisit classic fossil and stone tool sites in Olduvai Middle and Upper Bed II. This interval of time (~1.79 - 1.15 million years) at Olduvai preserves evidence for critical changes in early hominid and animal fossils, stone tools, and climate, including the disappearance of Homo habilis, the emergence of Homo erectus, the end of primitive Oldowan stone tools, and the first appearance of more advanced Acheulean tools. Unlike at many other African archaeological sites, many Olduvai artifacts are found in primary or near-primary context, providing additional information on hominid behavior. Little field research has been conducted on Middle and Upper Bed II since M.D. Leakey's original studies over 40 years ago.Despite the importance of Olduvai Bed II, the age and stratigraphic position of the excavated sites is poorly constrained. Estimates for the age of the top of Bed II range from 1.4 to 1.0 million years. This 400,000-year range makes it impossible to compare the Olduvai record chronologically with other potentially contemporaneous sites in Eastern Africa, and makes it difficult to incorporate the vast amount of archaeological data from Olduvai into regional studies of hominin evolution. To address this, this study will date volcanic ashes from Bed II using innovative 40Ar/39Ar radiometric methods.In addition to providing better dates for regional correlation this project will improve site-to-site correlation within Olduvai. This project will study volcanic ashes within the Olduvai sediments, determining unique compositional "fingerprints" for each ash and using these to identify individual ashes at different sites. By analyzing ashes above and below archaeological sites, this project will construct a new stratigraphic framework for Bed II. Using this high-resolution framework this project will test whether the "Developed Oldowan" archaeological sites clustered around the margins of ancient Olduvai lake coexisted with the more inland Early Acheulean. A renewed investigation of the artifacts using modern assemblage interpretations will help test whether these two assemblages actually represent unique industries, or whether they are adaptive responses to different ecological settings.The intellectual merit of this project is the establishment of a new, geochemically tested stratigraphic framework for Olduvai Bed II that can test and refine the relative ages of its archaeological sites. New dates will provide age control for this notoriously poorly dated interval, and relate the Olduvai record to regional records of climate and technological change. The re-examination of Bed II Developed Oldowan and Acheulean assemblages will combine field and laboratory work to provide a modern reappraisal of the sites where the Oldowan - early Acheulean sequence was originally defined.The broader impact of this study is that it will improve understanding of Olduvai's chronological and archaeological place in the records of human evolution, technological development, and climate change. This project will provide training for U.S., U.K., and Tanzanian students and will help improve the paleoanthropological facilities at the Tanzanian National History Museum.