| Autor: |
Yuskar, Yuniarti, Bartz, Melanie, Schmidt, Christoph, Choanji, Tiggi, Lane, Stuart N., King, Georgina E. |
| Předmět: |
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| Zdroj: |
Ancient TL; Jun2023, Vol. 41 Issue 1, p222-222, 1p |
| Abstrakt: |
Fluvial sediments coupled with robust geochronology provide a valuable archive of environmental change. Quaternary landscape evolution in tropical environments, such as Indonesia, remains poorly constrained due to limited prior studies as well as challenging mineral properties for luminescence dating. In this study, we explore the application of luminescence dating for sediments from the Kampar River, Sumatra Island, Indonesia, with the objective of reconstructing its Quaternary fluvial dynamics. Sediment samples were taken from terrace deposits of different elevations. Initial quartz SAR measurements were made using blue and green stimulation and a double SAR protocol. Neither blue nor green stimulated signals were dominated by a fast component. Most quartz aliquots also failed the IRdepletion test suggesting feldspar contamination. However, SEM analyses indicate that no feldspars were present in the quartz extracts. As the quartz properties were unsuitable, we tested post-IR50 IRSL225 of K-feldspar which yielded good signal intensities despite limited feldspar being present in our samples. Residual doses were a few Gys and dose recovery test results were within 10 - 15% of unity, indicating that the protocol is suitable for these samples. Resultant IR50 and pIRIR225 dose distributions yielded large overdispersion values (between 39 and 80 %) due to partial bleaching. Ages were therefore calculated using the minimum age model. The observed pIRIR225 fading rates (mean g2days= 0.94 ± 1.38%/decade) were significantly lower than those measured at 50°C (mean g2days = 4.48 ± 1.63%/decade). Fading uncorrected pIR225 ages and fading corrected IR50 ages were in agreement, highlighting the potential of using the luminescence of feldspar for dating in Indonesia. Our chronology reveals that since MIS6, the Kampar river has aggraded during glacial periods, these data will be coupled with fluvial dynamics modelling to better understand the fluvial response to a changing climate. [ABSTRACT FROM AUTHOR] |
| Databáze: |
Complementary Index |
| Externí odkaz: |
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