Which geomorphic processes can be informed by luminescence measurements?
Which geomorphic processes can be informed by luminescence measurements?
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DOI：
10.1016/j.geomorph.2020.107296
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发表时间：
2020-10-15
期刊：
影响因子：
3.9
通讯作者：
Brown, N. D.
中科院分区：
文献类型：
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作者：
Brown, N. D.
石英和长石的发光信号包含了大量暴露在高温和阳光下的信息。虽然许多研究都集中在量化单个过程，如谷物运输和埋葬，挖掘过程中的冷却，或新暴露的岩石表面的漂白，但还没有多少工作来说明这些影响是如何相互作用的。例如，地貌学家如何解释河边鹅卵石或最近从隆起的地形上落下的岩石中的发光信号？本研究试图解决这一问题，首先提出了一个简单的动力学表达式，用于响应背景辐射的OSL信号积累，以及暴露于热或直射或减弱的阳光下的OSL损失。然后使用该模型来模拟三个示例示例历史。模拟结果表明，在一个样品的发光信号中可以嵌入多少信息，以及不同的地貌历史如何产生惊人相似的信号。提出了可以用发光信号检测的温度和时间尺度，并与各种地貌过程的温度和时间尺度进行了比较。最后，模拟结果说明了使用不同稳定性的信号来更好地了解样品最近的地质历史的好处。(c) 2020 Elsevier B.V.版权所有
Luminescence signals fromquartz and feldspar contain a wealth of information about exposure to heat and sunlight. While many studies have focused on quantifying individual processes such as grain transport and burial, cooling during exhumation, or bleaching of freshly exposed rock surfaces, not much work has yet been done to illustrate how these effects might interact. For example, how might a geomorphologist interpret the luminescence signals within a riverine cobble or within a recent rockfall from an uplifting terrain? This study attempts to address this issue by first presenting a simple kinetic expression for OSL signal accumulation in response to background radiation, and OSL loss by exposure to heat or to direct or attenuated sunlight. This model is then used to simulate three example sample histories. Simulation results demonstrate how much information can be embedded within one sample's luminescence signal and how disparate geomorphic histories can produce strikingly similar signals. The temperatures and timescales which can be examined with luminescence signals are presented in comparison to those of various geomorphic processes. Finally, simulation results illustrate the benefit of using signals of different stability to better understand a sample's recent geologic history. (c) 2020 Elsevier B.V. All rights reserved.