Radiocarbon Dating of a Speleothem Record of Paleoclimate for Angkor, Cambodia
Radiocarbon Dating of a Speleothem Record of Paleoclimate for Angkor, Cambodia
复制标题
DOI：
10.1017/rdc.2017.115
复制
发表时间：
2017-12
期刊：
影响因子：
8.3
通讯作者：
Q. Hua;Duncan E. Cook;J. Fohlmeister;D. Penny;P. Bishop;S. Buckman
中科院分区：
文献类型：
--
作者：
Q. Hua;Duncan E. Cook;J. Fohlmeister;D. Penny;P. Bishop;S. Buckman
摘要：我们报告了柬埔寨南部一根石笋PC1顶部的年代构建情况，目的是重建一份连续的高分辨率气候记录，涵盖中世纪高棉王国及其首都吴哥的繁荣与衰落（公元约9世纪 - 15世纪）。先前使用标准铀 - 钍法对PC1进行测年的尝试未获成功。因此，我们使用放射性碳对这根石笋进行了测年。沿着PC1的生长轴采集了50个碳酸盐样本，用于加速器质谱（AMS）分析。PC1的年代重建采用了Hua等人（2012a）和Lechleitner等人（2016a）所描述的两种不同方法。两种年龄 - 深度模型之间的高度一致性表明，PC1顶部约47毫米是在过去一千年中生长的，在公元约1250 - 1650年期间存在生长间断，这是由于在34.4 - 35.2毫米深度处测量到的¹⁴C值发生了巨大变化。生长间断的时间涵盖了区域气候记录所显示的公元14世纪 - 16世纪长达数十年的干旱时期。
Abstract We report the chronological construction for the top portion of a speleothem, PC1, from southern Cambodia with the aim of reconstructing a continuous high-resolution climate record covering the fluorescence and decline of the medieval Khmer kingdom and its capital at Angkor (~9th–15th centuries AD). Earlier attempts to date PC1 by the standard U-Th method proved unsuccessful. We have therefore dated this speleothem using radiocarbon. Fifty carbonate samples along the growth axis of PC1 were collected for accelerator mass spectrometry (AMS) analysis. Chronological reconstruction for PC1 was achieved using two different approaches described by Hua et al. (2012a) and Lechleitner et al. (2016a). Excellent concordance between the two age-depth models indicates that the top ~47 mm of PC1 grew during the last millennium with a growth hiatus during ~1250–1650 AD, resulting from a large change in measured 14C values at 34.4–35.2 mm depth. The timing of the growth hiatus covers the period of decades-long droughts during the 14th–16th centuries AD indicated in regional climate records.