Collaborative Research: Radiocarbon Dating of Mesoamerican Lime Mortars and Plasters

合作研究：中美洲石灰砂浆和灰泥的放射性碳测年

• 批准号: 0514406
• 负责人: Gregory Hodgins
• 金额: $ 7.71万
• 依托单位: University of Arizona
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 2005
• 资助国家: 美国
• 起止时间: 2005-08-01 至 2008-07-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=0514406&HistoricalAwards=false
• 关键词: Collaborative; Research; Radiocarbon; Dating; Mesoamerican

With National Science Foundation support, an interdisciplinary and multi-institutional team including faculty and students from the University of Arizona (Dr. Greg Hodgins and Ms. A.J. Vonarx) and Arizona State University (Dr. George Cowgill, Dr. Arleyn Simon, and Mr. Tatsuya Murakami) will explore a method for directly dating mortars and plasters within Mesoamerican monumental structures based upon their radiocarbon content. Mortars and plasters harden by the incorporation of atmospheric carbon dioxide into their structure, thus fixing the 14C-content of the material at the time of construction and offering the possibility of dating construction events. Refinement of Mesoamerican chronology will provide insights into technological style, regional variation, and temporal change and continuity. At present, the radiocarbon dating of lime-based construction materials has been carried out predominantly within European and Middle Eastern contexts. Yet, the application of the approach to Mesoamerican materials is ideal, given the widespread use of lime-based products and our growing knowledge of prehispanic lime plaster technology. Previous research by the team indicates that the optimal strategy for method development requires simultaneously dating mortar or plaster carbonates along with organic inclusions isolated from them. The project will analyze materials with well established organic inclusion contents selected from a variety of archaeological contexts to investigate the robustness of the method.The group will date materials from three sites within Mesoamerica: El Naranjal, Quintana Roo, Mexico, and Tecalote, Guatemala, in the Maya Lowlands; and, the Pyramid of the Moon, Teotihuacan, in Highland Mexico. From the first two sites, mortar or plaster samples containing organic inclusions that can be radiocarbon dated in parallel with mortar and plaster carbonates will be obtained. Plaster samples from numerous construction phases of the Pyramid of the Moon are also available. Several have stratigraphic association with both ceramic and radiocarbon dated layers. The interdisciplinary team has expertise in Mesoamerican archaeology, artifact and materials characterization, studies of ancient technology, and radiocarbon dating. Accessible facilities are ideal for this work and include the Archaeological Research Institute and Goldwater Center for Solid State Science at Arizona State University and the NSF-Arizona Accelerator Mass Spectrometry Laboratory and the Department of Anthropology Archaeometry Laboratories at the University of Arizona.The broader impacts of the study are that it will advance the application of AMS radiocarbon dating to lime mortars and plasters in Mesoamerica allowing archaeologists to date construction episodes. This method has potentially broad application given the widespread use of lime plasters and mortars throughout Mesoamerica over long periods of time. The development of mortar dating methods within the NSF-Arizona AMS Laboratory will potentially allow such analyses to be offered to the archaeological community on a regular basis and will make substantive contributions to the refinement of Mesoamerican chronology and interpretation of this complex and fascinating region. Two graduate students will be trained in radiocarbon sample preparation procedures and will utilize this research as part of their doctoral dissertations in anthropological archaeology and archaeological science. Undergraduate students will participate in the compositional study of the samples and their preparation for dating. The characterization and collection of datable plasters will involve continued cooperation with colleagues and institutions in Mexico and Guatemala. These findings will be shared on an international level through presentations and publications in natural science, archaeology, and social science.

在美国国家科学基金会的支持下，一个跨学科和多机构的团队，包括来自亚利桑那大学（Greg Hodgins博士和A. J. Vonarx女士）和亚利桑那州立大学（乔治考吉尔博士，Arleyn Simon博士和村上达也先生）的教师和学生，将探索一种基于放射性碳含量直接测定中美洲纪念性建筑内砂浆和石膏年代的方法。砂浆和灰泥通过将大气中的二氧化碳结合到其结构中而硬化，从而在施工时固定材料的14 C含量，并提供了确定施工事件日期的可能性。中美洲年表的完善将提供对技术风格，区域变化，时间变化和连续性的见解。目前，石灰基建筑材料的放射性碳测年主要在欧洲和中东地区进行。然而，考虑到石灰基产品的广泛使用和我们对前西班牙石灰石膏技术的不断了解，将这种方法应用于中美洲材料是理想的。该团队先前的研究表明，方法开发的最佳策略需要同时测定砂浆或石膏碳酸盐沿着从中分离出的有机包裹体。该项目将分析从各种考古背景中选择的具有良好有机包裹体含量的材料，以调查该方法的鲁棒性。该小组将对中美洲三个地点的材料进行日期确定：墨西哥金塔纳罗奥的El Naranjal和危地马拉的Tecalote，玛雅低地;以及墨西哥高地的Teotihuacan的月球金字塔。从前两个地点，将获得含有有机包裹体的砂浆或灰泥样品，这些样品可以与砂浆和灰泥碳酸盐平行进行放射性碳年代测定。月球金字塔的许多施工阶段的石膏样品也可提供。有几个与陶瓷和放射性碳年代测定层都有地层联系。该跨学科团队拥有中美洲考古学，人工制品和材料表征，古代技术研究和放射性碳测年的专业知识。可扩展的设施是这项工作的理想选择，包括亚利桑那州立大学的考古研究所和戈德华特固态科学中心以及美国国家科学基金会-亚利桑那加速器质谱实验室和亚利桑那大学人类学考古学实验室。这项研究的更广泛影响是，它将推动AMS放射性碳测年在中美洲石灰砂浆和石膏中的应用，考古学家确定建筑年代由于在整个中美洲长期广泛使用石灰灰泥和砂浆，这种方法具有潜在的广泛应用。国家科学基金会-亚利桑那州AMS实验室的砂浆测年方法的发展将有可能使这种分析定期提供给考古界，并将作出实质性的贡献，完善中美洲年表和解释这个复杂而迷人的地区。两名研究生将接受放射性碳样品制备程序的培训，并将利用这项研究作为他们人类学考古学和考古学博士论文的一部分。本科生将参与样品的成分研究和他们的约会准备。将继续与墨西哥和危地马拉的同事和机构合作，对可确定年代的石膏进行定性和收集。这些发现将通过自然科学，考古学和社会科学的演讲和出版物在国际层面上分享。