Infrared-Radiofluorescence (IR-RF) Dating of loess samples with independent age control from central Alaska – further investigations to establish IR-RF as a resilient dating method

红外放射荧光 (IR-RF) 对来自阿拉斯加中部的黄土样本进行独立年龄控制的测年——进一步研究以建立 IR-RF 作为一种弹性测年方法

• 批准号: 418012553
• 负责人: Dr. Tobias Lauer
• 金额: --
• 依托单位: GEOTOP
• 依托单位国家: 德国
• 项目类别: Research Fellowships
• 财政年份: 2018
• 资助国家: 德国
• 起止时间: 2017-12-31 至 2018-12-31
• 项目状态: 已结题
• 来源: https://gepris.dfg.de/gepris/projekt/418012553?language=en
• 关键词: Infrared; Radiofluorescence; IR; RF; Dating

Infrared Radiofluorescence (IR RF) dating is a method to determine the last sunlight exposure of sediment grains. The method is applied to potassium feldspar, has the potential to date back several 100 ka and the IR RF signal is characterized by high stability. Hence, the dating method is an important alternative to luminescence dating and it is especially relevant to establish chronological frameworks for Middle Pleistocene sediments. Until now, there are still several methodological issues related to IR RF, that need to be solved and only few dating laboratories apply IR RF. To obtain a higher acceptance of the method among dating specialists and Quaternary scientists further investigations are mandatory and it has to be outlined that IR-RF yields resilient chronological results. The aim of this research project is to test and further develop the IR RF method by applying IR RF to fine-grain samples with independent age control mainly taken from northern American loess-palaeosol sequences. The age of the samples ranges from the Holocene to the Middle Pleistocene. Dose recovery tests will be applied to modify the IR RF single aliquot protocol. Furthermore, experiments concerning the bleachability and the saturation behavior of the IR RF signal will be conducted. The reliability of final equivalent dose measurements and age determinations can be observed due to the given independent age control of investigated samples.Based on the results of the experiments, we intend to obtain a more detailed understanding of physics (electron pathways) behind the IR RF emission. Finally, the aim is to provide a dating approach that fulfills the high quality criteria needed in the field of Quaternary dating methods.

红外辐射荧光测年是确定沉积物颗粒最后一次日照时间的一种方法。将该方法应用于钾长石样品中，测得的红外射频信号具有较高的稳定性，可追溯到几百ka以前。因此，该测年方法是发光测年的一种重要替代方法，对建立中更新世沉积物的年代学格架具有特别重要的意义。到目前为止，仍有几个与红外射频相关的方法学问题需要解决，只有少数几个测年实验室应用于红外射频。为了使测年专家和第四纪科学家对该方法有更高的接受度，必须进行进一步的调查，必须概述的是，IR-RF产生了具有弹性的年代学结果。本研究项目的目的是通过将红外射频应用于主要取自北美黄土-古土壤序列的独立年龄控制的细粒样品来检验和进一步发展红外射频方法。样品的年龄范围为全新世至中更新世。将应用剂量恢复测试来修改IR射频单等分协议。此外，还将进行关于红外射频信号的漂白能力和饱和行为的实验。由于被调查样品具有独立的年龄控制，所以最终的等效剂量测量和年龄测定的可靠性可以观察到。基于实验结果，我们打算对红外射频发射背后的物理(电子路径)有更详细的了解。最后，目的是提供一种满足第四纪测年方法领域所需的高质量标准的测年方法。