Radiocarbon Dating of Collagen-degraded Bone: The Use of Ostecalcin

泰勒博士和他的同事们将进行探索性研究，以确定将骨钙素用于放射性碳枣骨的可行性。该项目由三个部分组成。首先从样品骨中提取骨钙素，并通过分析GLA和Hyp的含量来确定其纯度。其次，从已知年龄超过10万年的骨骼中提取骨钙素，然后进行放射性碳测年。人们预计，放射性活动不会超过本底水平。最后，骨钙素将从克洛维斯时代遗址(约10000年前)退化的骨骼中提取。这也将是放射性碳年代和结果的准确性确定。骨的大部分有机部分由胶原蛋白组成，许多实验表明，如果这种胶原蛋白在沉积后过程中不被严重降解，它可以得到准确的放射性碳年龄。然而，同样清楚的是，降解的胶原蛋白往往会产生异常的结果。骨钙素是一种非胶原的有机物质，也存在于骨骼中，初步结果使泰勒和他的同事相信，它可能为退化的骨骼提供准确的日期。这一初步探索性项目将用于评估这一方法，并有望为更大规模的工作提供基础。这项研究不仅对考古学家很重要，而且对其他希望确定过去年代的科学家也很重要。骨骼往往是考古遗址和其他史前环境中保存下来的唯一有机材料。虽然它有时是可以约会的，但通常它的化学变化太大，不能产生好的结果。这里开发的技术可能会解决这个问题。

Dr. Taylor and his colleagues will conduct exploratory research to determine the feasibility of using osteocalcin to radiocarbon date bone. The project consists of three parts. First osteocalcin will be extracted from sample bone and its purity determined through analysis of amounts of Gla and Hyp present. Secondly osteocalcin will be extracted from bone with known age of greater than 100,000 years and then radiocarbon dated. One would expect that radioactive activity would not exceed background levels. Finally osteocalcin will be extracted from degraded bone which derives from Clovis age sites (ca. 10,000 years old). This also will be radiocarbon dated and the accuracy of the results determined. Most of the organic fraction of bone consists of collagen and many experiments have shown that if this collagen is not seriously degraded by post depositional processes it can yield accurate radiocarbon ages. However it is also clear that degraded collagen often given anomalous results. Osteocalcin is a non- collagen organic material which is also present in bone and preliminary results lead Taylor and his colleagues to believe that it may provide accurate dates for degraded bone. This preliminary exploratory project will serve to evaluate this approach and hopefully provide the basis for more large scale work. This research is important not only for archaeologists but other scientists who wish to date the past. Bone is often the only organic material preserved in archaeological sites and other prehistoric contexts. While it is sometimes datable, often it is too chemically altered to give good results. The technique developed here may remedy this problem.