Surface paleothermometry using low-temperature thermoluminescence of feldspar
Surface paleothermometry using low-temperature thermoluminescence of feldspar
复制标题
利用长石低温热释光进行表面古测温
DOI：
10.5194/cp-16-2075-2020
复制
发表时间：
2020
影响因子：
4.3
通讯作者：
A. Singhvi
中科院分区：
文献类型：
--
作者：
R. Biswas;F. Herman;G. King;B. Lehmann;A. Singhvi
抽象的。长石的热释光（TL）的潜力，以提取暴露在地球表面的岩石所经历的温度历史进行了研究。实验室中观察到的长石热释光信号是由俘获能的连续分布释放出的俘获电子引起的，这种分布具有一定的热稳定性。俘获能量的分布，或热稳定性，是这样的，在室温下被俘获的电子的寿命从不到一年到几十亿年不等。较短的寿命与低温TL信号或峰值相关联，而较长的寿命与高温TL信号相关联。在这里，我们表明，与较短的寿命，或较低的温度TL信号（即，在200 °C和250 °C之间），对地质时间尺度上地球表面发生的温度波动很敏感。此外，我们表明，它是可能的重建过去的地表温度的历史，在陆地设置利用连续分布的捕获能量。该方法的潜力首先通过理论实验进行测试，在该实验中，将周期性温度历史应用于封装TL-测温的动力学特性的动力学模型。然后，我们使用贝叶斯方法将TL测量值转化为岩石的温度历史，假设过去的温度变化遵循所观察到的δ 18 O异常。最后，我们对在Mer de Glace（欧洲阿尔卑斯山勃朗峰地块）收集的两个样本进行了测试，并发现两个样本的温度历史相似。结果表明，长石热释光可以作为古温度计。
Abstract. Thermoluminescence (TL) of feldspar is investigated for its potential to extract temperature histories experienced by rocks exposed at Earth’s surface. TL signals from feldspar observed in the laboratory arise from the release of trapped electrons from a continuous distribution of trapping energies that have range of thermal stabilities. The distribution of trapping energies, or thermal stabilities, is such that the lifetime of trapped electrons at room temperature ranges from less than a year to several billion years. Shorter lifetimes are associated with low temperature TL signals, or peaks, and longer lifetimes are associated with high temperature TL signals. Here we show that trapping energies associated with shorter lifetimes, or lower temperature TL signals (i.e., between 200 °C and 250 °C), are sensitive to temperature fluctuations occurring at Earth’s surface over geological timescales. Furthermore, we show that it is possible to reconstruct past surface temperature histories in terrestrial settings by exploiting the continuous distribution of trapping energies. The potential of this method is first tested through theoretical experiments, in which a periodic temperature history is applied to a kinetic model that encapsulates the kinetic characteristics of TL-thermometry. We then use a Bayesian approach to invert TL measurements into temperature histories of rocks, assuming that past temperature variations follow the observed δ18O anomalies. Finally, we test the approach on two samples collected at the Mer de Glace (Mont Blanc massif, European Alps) and find similar temperature histories for both samples. Our results show that TL of feldspar may be used as a paleo-thermometer.
影响因子：
2.7
作者：
Durcan, Julie A.;King, Georgina E.;Duller, Geoffrey A. T.
通讯作者：
Duller, Geoffrey A. T.