Petrographic, ICP-MS, and LA-ICP-MS Sourcing of Quartzite Sources, Gunnison Basin, Colorado

在美国国家科学基金会的支持下，Bonnie Pitblado博士和Carol Dehler博士将进行实验，以确定岩相学(显微)和地球化学方法在多大程度上可以用来表征科罗拉多州西南部甘尼森盆地石英岩来源的独特“指纹”。考古学家和地质学家之前都没有开发出寻找石英岩的方法，但这种岩石类型是世界上最普遍的，而且自古以来许多史前人类都喜欢用它来制造投射点、刮刀和其他碎石工具。这项研究将扩大匹布拉多和德勒在2005-2006年进行的试点来源研究，这项研究表明，与传统观点相反，可以根据显微特征和化学成分来区分不同来源的石英岩。这项由美国国家科学基金会资助的研究将：(A)利用地质考古模型对甘尼森盆地十几个不同的石英岩建造和众多石英岩次生砾石矿床进行定位和取样；(B)确定区分来源的最佳方法(S)；以及(C)对同样位于甘尼森盆地、有8000年历史的Chance Gulch遗址的石英岩进行剖面考古，以确定其在地形上最有可能的采石源。这项研究的“c”部分将允许研究人员重建落基山脉一些最古老的狩猎-采集者的景观用途。这一点很重要，因为无论是生态学理论，还是从考古学上获得的少量数据都表明，落基山脉早期的狩猎采集者遵循的是受地理限制的年度轮回，这与大平原等更知名的地区形成了鲜明对比。确认或拒绝这一建议将有助于考古学家了解北美大陆的所有生态多样性。犹他州立大学的合作者邦妮·皮布拉多是古印度考古学家，卡罗尔·德勒是地质学家，他们将与地球化学源专家赫克托·内夫(加州大学长滩分校)、地球化学家斯蒂芬·纳尔逊(杨百翰大学)和统计学家丹尼斯·埃盖特(也是杨百翰大学的)合作进行研究。高级人员将为这项工作带来广泛的专业知识领域，并将最大限度地增加成功完成这项为期三年的项目的所有组成部分的机会。这项研究最重要的智力贡献在于方法和理论领域。在方法上，该项目将改进目前尚不存在的石英岩指纹识别技术，这一贡献将受到旨在解决一系列研究问题的地球科学家的重视。从理论上讲，这项研究将有助于完善考古学对落基山脉和北美总体殖民的理解。就更广泛的影响而言，该研究计划将在现场和实验室培训本科生。大约20名学生将帮助收集石英岩样本，另有4至5名学生将接受培训，对样本进行岩相学分析。此外，联合PI将继续招募北部、南部和犹特山犹特高中生参加实地考察的传统。这将使学生了解他们在落基山狩猎采集的前辈的生活方式；赚取大学和高中学分；并接触到大学氛围，最好是让他们以后进入大学。

With National Science Foundation support, Drs. Bonnie Pitblado and Carol Dehler will conduct experiments to determine the extent to which petrographic (microscopic) and geochemical methods can be used to characterize the unique "fingerprints" of quartzite sources in the Gunnison Basin, southwest Colorado. Neither archaeologists nor geologists have previously developed methods for sourcing quartzite, yet this rock type is the most ubiquitous in the world, and many prehistoric people throughout time preferred to use it to manufacture their projectile points, scrapers, and other chipped stone tools.The research will expand pilot sourcing studies conducted by Pitblado and Dehler in 2005 - 2006, which suggested that contrary to conventional wisdom, distinct sources of quartzite can be discriminated from one another both on the basis of microscopic characteristics and chemical composition. The NSF-supported research will (a) use a geoarchaeological model to locate and sample a dozen different quartzite formations and numerous secondary gravel deposits of quartzites in the Gunnison Basin; (b) confirm the best method(s) for differntiating among the sources; and (c) profile archaeological occurrences of quartzite at the 8,000 year-old Chance Gulch site, also in the Gunnison Basin, to determine their likeliest quarry sources on the landscape. Component "c" of the research will allow the researchers to reconstruct the landscape use of some of the most ancient hunter-gatherers in the Rocky Mountains. This is important because both ecological theory and what little archaeologically derived data exist suggest that early hunter-gatherers in the Rockies, in stark contrast to better-known regions like the Great Plains, followed a geographically restricted annual round. Confirming or rejecting this suggestion will contribute to archaeologists' understanding of the peopling of North America, in all the continent's ecological variability.Utah State University co-PIs Bonnie Pitblado, a Paleoindian archaeologist, and Carol Dehler, a geologist, will collaborate in the research with geochemical sourcing specialist Hector Neff (University of California, Long Beach), geochemist Stephen Nelson (Brigham Young University), and statistician Dennis Eggett (also of Brigham Young University). Senior personnel bring to the undertaking a wide range of areas of expertise and together will maximize the chances for successfully completing all components of the three-year project.The most important intellectual contributions of the research lie in the realms of both method and theory. Methodologically, the project will refine currently non-existent techniques for fingerprinting quartzite"a contribution that will be valued by earth scientists aiming to solve a host of research problems. Theoretically, the research will help refine archaeological understanding of the colonization of the Rockies and North America in general. In terms of broader impacts, the research program will train undergraduate university students both in the field and in the laboratory. About twenty students will help collect the quartzite samples and another four or five will be trained to conduct petrographic analyses of the samples. As well, the co-PIs will continue a tradition of recruiting Northern, Southern and Ute Mountain Ute high school students to participate in the fieldwork. This will allow the students to learn about the life ways of their Rocky Mountain hunter-gatherer predecessors; to earn college and high school credits; and to gain exposure to a university atmosphere ideally resulting in their later matriculation to college.