The application of radiofluorescence dating (IR-RF) on loess

黄土及其古土壤是研究第四纪古环境的重要沉积档案。然而，为了解释这些档案，一个可靠的年代地层学是至关重要的，发光测年技术在建立这些年代地层学方面起着重要作用。到目前为止，由于特殊的矿物特征和应用发光测年技术的方法问题，末次冰期/间冰期的黄土主要采用了发光测年方法。红外辐射荧光测年技术（IR/RF）是另一种创新的方法，它可以测定远远超过末次冰期-间冰期旋回的沉积物的年代。然而，尽管红外/射频测年技术已经可以成功地应用于各种沉积物类型，但它的常规应用并没有给出，并且开发可靠的红外/射频测年方案是具有挑战性的。因此，需要回答有关IR/RF信号对单个测量参数的行为的基本问题，这是开发可靠的IR/RF测年测量协议的先决条件。本课题拟建立黄土（> ~ 63µm）粗粒钾长石的红外/射频测年技术。因此，将研究不同的测量参数及其对IR/RF测年结果的影响，以制定可靠的IR-RF测量方案。该应用程序的第二个目标是为多矿物细粒黄土样品（4至11 μ m）开发新的IR-RF定年方案。由于红外/射频测年技术，即粗粒钾长石测年技术和多矿物细粒样品测年技术，对晚更新世至中更新世黄土沉积物的测年具有很大的潜力，因此新方法的开发将利用已存在独立年龄控制的晚更新世至中更新世黄土材料。

Loess and its paleosols represent important sedimentary archives for investigating Quaternary paleoenvironments. However, to interpret these archives, a robust chronostratigraphy is of crucial importance and luminescence dating techniques play a major role in establishing these chronostratigraphies. So far, dominantly loess from the last glacial/interglacial cycle was successfully dated by luminescence dating, caused by specific mineral characteristics and due to methodological problems of the applied luminescence dating techniques. An alternative and innovative approach is represented by the infrared radiofluorescence dating technique (IR/RF), which enables the dating of sediments far beyond the last glacial-interglacial cycle. However, even though the IR/RF dating technique could already successfully be applied to various sediment types, its routine application is not given and the development of a reliable IR/RF dating protocol is challenging. Therefore, basic questions in respect to the behavior of the IR/RF signal to individual measurement parameters need to be answered, a prerequisite to develop a robust measurement protocol for IR/RF dating. Here we apply for a project, which focus on establishing the IR/RF dating technique for coarse grain K-feldspar of loess (> 63 µm). Therefore, different measurements parameters and their impact on the IR/RF dating results will be investigated, to develop a reliable IR-RF measurement protocol. The second objective of this application is the development of a new IR-RF dating protocol for polymineral fine grain loess samples (4 to 11 µm). Because both IR/RF dating techniques, the technique for coarse-grain K Feldspar and polymineral fine grain samples, have a great potential for the dating of loess deposits from the late to middle Pleistocene, the development of the new methods will use loess material from the late to middle Pleistocene, for which already independent age control exists.