Collaborative Research: The Extension of a Dendrochronological Sequence to Northern Mesoamerica

合作研究：树木年代序列向中美洲北部的延伸

• 批准号: 1755504
• 负责人: Paula Turkon
• 金额: $ 9.85万
• 依托单位: Ithaca College
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2018
• 资助国家: 美国
• 起止时间: 2018-05-01 至 2024-09-30
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1755504&HistoricalAwards=false
• 关键词: Collaborative; Research; Extension; Dendrochronological; Sequence

Drs. Paula Turkon, Sturt Manning, and Carol Griggs, along with colleagues from Mexico, will conduct research to provide a high-resolution absolute tree-ring chronology for Northern Mesoamerican archaeological sites using a combination of tree-ring and AMS radiocarbon data. This project extends their preliminary research both geographically and chronologically, with the goal of linking the existing Epiclassic chronology from Northwestern Mesoamerica that ends in the 8th century A.D., to the regionally extensive, calendar-dated chronologies from living and relic trees in the same region. The dendrochronological results will offer dating precision to archaeologists working in these regions for time periods that do not have written sources of chronological data. It will also establish the foundation for climate reconstruction studies that, in the future, will help clarify the long-term relationships between the magnitude of climatic change and human response. In fostering close collaboration between archaeologists, dendrochronologists, graduate, and undergraduate students from multiple institutions throughout Mexico and the United States, this project's mission is to encourage the application of dendroarchaeology [=archaeological dendrochronology], currently not part of archaeological fieldwork or analysis in Mexico. Mesoamerican archaeologists have long acknowledged the need for precise dating methods in order to understand cultural change, particularly in the region north of the core of Mesoamerican culture. Yet despite tremendous success in the development of tree-ring dating of archaeological sites just north in the American Southwest, and the more recent development of long tree-ring chronologies in Mexico that cover the past 1300 years, dendroarchaeology has been virtually absent in Mesoamerica. The first stage of this NSF funded project demonstrated the availability, measurability, and similarities in growth patterns ("crossdatability") of archaeological tree-ring samples in Northwestern Mesoamerica from the 5th to 8th centuries A.D. In this second stage, the researchers will incorporate archaeological samples from Postclassic and historic sites located in a broader geographic region in northern Mesoamerica. Because the new archaeological collections of wood will likewise be from a time period for which there are no well-established master chronologies, the tree-ring sequences produced from the prehispanic sites will be initially anchored in time by "radiocarbon wiggle-matching." This method fits a known relative sequence of radiocarbon dates from specific tree-rings against the radiocarbon calibration curve to achieve a precise fit and thus calendar placement with minimal error. Ultimately, we intend to create a continuous tree-ring record from the present back to the Classic period, using both the archaeological and historic collections, as well as existing calendar-dated chronologies. The resulting data will not only fill a significant gap in our knowledge of the chronology of Northern Mesoamerica, but help address broader questions such as the rate, timing, and directionality of cultural influences with the Mesoamerican cultural core. Since dendroarchaeological methods are cumulative and iterative, the chronologies will gain in length, sample depth, and robustness, and will become increasingly useful to archaeologists working in broader geographic regions and time periods.This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.

保拉·图尔肯博士、斯特特·曼宁博士和卡罗尔·格里格斯博士将与来自墨西哥的同事一起进行研究，利用树木年轮和AMS放射性碳数据的组合，为中美洲北部的考古遗址提供高分辨率的绝对年轮年表。该项目从地理和年代两个方面扩展了他们的初步研究，目的是将现有的中美洲西北部至公元8世纪结束的表层纪年表与同一地区活树和遗迹树的区域范围广泛的历法年代学联系起来。树状年代学结果将为在这些地区工作的考古学家提供准确的年代测定，这些时间段没有书面的年代学数据来源。它还将为未来的气候重建研究奠定基础，这些研究将有助于澄清气候变化的严重程度与人类反应之间的长期关系。为了促进来自墨西哥和美国多个机构的考古学家、树状年代学家、研究生和本科生之间的密切合作，该项目的任务是鼓励树状考古学[=考古树状年代学]的应用，目前树状考古学不是墨西哥考古野外工作或分析的一部分。中美洲考古学家长期以来一直承认，需要精确的年代测定方法来了解文化变化，特别是在中美洲文化核心以北的地区。然而，尽管在美国西南部北部考古遗址的树轮测年方面取得了巨大的成功，而且墨西哥最近又开发了覆盖过去1300年的长树轮年代学，但树枝考古学在中美洲几乎没有。美国国家科学基金会资助的这个项目的第一阶段展示了公元5世纪至8世纪在中美洲西北部的考古年轮样本的可用性、可测量性和生长模式(“可交叉更新”)的相似性。在第二阶段，研究人员将结合来自位于中美洲北部更广阔地理区域的后古典和历史遗址的考古样本。由于新的木材考古收藏品同样将来自一个没有确定的主年表的时期，从理解遗址产生的树轮序列最初将通过“放射性碳摆动匹配”在时间上固定下来。这种方法将特定年轮的已知相对放射性碳日期序列与放射性碳校准曲线进行拟合，以实现精确的拟合，从而以最小的误差放置日历。最终，我们打算利用考古和历史收藏，以及现有的日历年代编年法，创建从现在到古典时期的连续树木年轮记录。由此产生的数据不仅将填补我们对中美洲北部年代学知识的重大空白，而且有助于解决更广泛的问题，如文化对中美洲文化核心的影响的速度、时间和方向性。由于树状考古方法是累积和迭代的，年表将在长度、样本深度和稳健性方面获得进展，并将对在更广泛的地理区域和时间段工作的考古学家变得越来越有用。该奖项反映了NSF的法定使命，并通过使用基金会的智力价值和更广泛的影响审查标准进行评估，被认为值得支持。