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，一个强大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中发挥了重要作用。到目前为止，主要是从末次冰期/间冰期循环黄土成功地定年的发光测年，造成特定的矿物特性，并由于应用发光测年技术的方法学问题。另一种创新的方法是红外线放射性荧光测年技术（IR/RF），这种技术能够测定沉积物的年代，远远超过最后一次冰期-间冰期循环。然而，即使红外/射频测年技术已经成功地应用于各种类型的沉积物，其常规应用程序没有给出，一个可靠的红外/射频测年协议的发展是具有挑战性的。因此，需要回答关于IR/RF信号对各个测量参数的行为的基本问题，这是开发用于IR/RF测年的稳健测量协议的先决条件。本文申请的项目是建立黄土中粗粒钾长石（> 63 µm）的IR/RF测年技术。因此，不同的测量参数及其对IR/RF测年结果的影响将被调查，以制定一个可靠的IR-RF测量协议。本申请的第二个目标是为多矿物细粒黄土样品（4至11 µm）开发一种新的IR-RF测年方案。由于粗粒钾长石和多矿物细粒样品的IR/RF定年技术在晚更新世至中更新世黄土沉积物的定年方面具有很大的潜力，因此新方法的发展将使用晚更新世至中更新世的黄土材料，因为已经存在独立的年龄控制。

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.