Optically stimulated luminescence dating of Late Quaternary glaciogenic sediments in the upper Hunza valley: validating the timing of glaciation and assessing dating methods
Optically stimulated luminescence dating of Late Quaternary glaciogenic sediments in the upper Hunza valley: validating the timing of glaciation and assessing dating methods
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DOI：
10.1016/s0277-3791(03)00220-8
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发表时间：
2004
影响因子：
4
通讯作者：
J. Spencer;L. Owen
中科院分区：
文献类型：
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作者：
J. Spencer;L. Owen
我们提出了一个全面的比较光释光（OSL）年龄与宇宙成因的放射性核素（CRN）年龄，和第一个研究，以验证CRN日期从冰碛石的发光日期从相关的冰碛石，完成直接和地层CRN和OSL采样点之间的关系。利用单等分光释光技术对12个晚第四纪冰川沉积物中的石英和钾长石进行了研究。在初步的添加剂剂量的红外刺激钾长石发光生长数据的快速信号饱和被解释为漂白的潜在发光不足的证据，这些数据引起了高估的年龄在大多数样品。进一步的分析集中在重复的单等分再生剂量（SAR）测量石英矿物使用蓝绿色的刺激。SAR灵敏度校正方法在两个样品中反复失败，另一个样品表现出明显的热传递。然而，罕萨河谷上游的八个冰川演替中有三个是用石英发光来定义的。尽管我们讨论了CRN数据中继承成分的可能性，但在古气候解释方面，两种测年技术都给出了一致的结果。
We present a comprehensive comparison of optically stimulated luminescence (OSL) ages with cosmogenic radionuclide (CRN) ages, and the first study to validate CRN dates from boulders on moraine ridges using luminescence dates from glaciogenic sediments from associated moraines, accomplished from both direct and stratigraphic relationships between CRN and OSL sampling sites. Both quartz and K-feldspars extracted from 12 Late Quaternary glaciogenic sediments were studied using single-aliquot OSL techniques. Rapid signal saturation in preliminary additive-dose infrared-stimulated K-feldspar luminescence growth data was interpreted as evidence of insufficiently bleached latent luminescence, and these data gave rise to overestimated ages in the majority of samples. Further analysis concentrated on replicated single-aliquot regenerative-dose (SAR) measurements of quartz minerals using blue-green stimulation. The SAR sensitivity correction method repeatedly failed in two of the samples and a further sample exhibited significant thermal transfer. Nevertheless, three of the eight glacial successions in the upper Hunza valley were defined using quartz-luminescence. Although we discuss the possibility of inherited components in the CRN data, in terms of paleoclimatic interpretations both dating techniques give concordant results.