Optically Stimulated Luminescence signal of quartz extracted from modern aeolian dust with known maximum age about decades was analyzed in terms of degree of bleaching. The results of dose recovery tests show that the modified double single-aliquot regenerative-dose protocol with the early background subtraction is robust for dating these modern dusts using small aliquots. Bleaching of these dusts is discussed based on the distribution of De values in histograms, scatter plots of De versus sensitivity corrected natural OSL signal and comparison between measured De and expected De. The results indicate that most dusts were completely bleached but some dusts were not completely bleached. The research suggests that cautions should be given to OSL ages younger than 1 ka in the western China close to deserts. Was southern Sweden ice free at 19—25 ka, or were the post LGM glacial fluvial sediments in-completely bleached?
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Luminescence, Fluvial Sediments
OSL dating of sediments from deserts in northern China - CORE
Both radiocarbon and optically stimulated luminescence OSL dating methods were applied to test their suitability for establishing a chronology of arid-zone lacustrine sediments using a 5. Although the radiocarbon and OSL ages agree in some samples, the radiocarbon ages are older than the corresponding OSL ages at the cm depth horizon late Pleistocene and in the —cm interval early to late Holocene. Grain-size analysis of early to late Holocene sediments and one late Pleistocene sediment sample cm depth indicates that eolian processes were the dominant sediment-transport mechanism. Also, two late Pleistocene sediments samples from to cm depths are interpreted to have been deposited by both eolian and glaciofluvial processes. Accordingly, the radiocarbon ages that were older than the corresponding OSL ages during the Holocene seem to have been a consequence of the influx of 14 C-deficient carbon delivered from adjacent soils and Paleozoic carbonate rocks by the westerly winds, a process that is also active today. In addition to the input of old reworked carbon by eolian processes, the late Pleistocene sediments were also influenced by old carbon delivered by deglacial meltwater.
OSL dating of sediments from deserts in northern China
Determination of deposition ages of sediments and radiation dosimetry are the primary applications of the luminescence dating method e. Aitken, ; Rittenour, ; Yukihara and McKeever, Recently, new applications have been extended to the field of sedimentary source identification and apportionment. Here the sensitivity of the detrital quartz to laboratory radiation is measured by means of thermoluminescence and optically stimulated luminescence.
The use of luminescence techniques to determine the depositional age of sediments transported and deposited by rivers and other fluvial systems. Dating fluvial sediments with luminescence techniques has utility to a wide range of applications such as investigating fluvial processes and alluvial stratigraphy or dating fluvial sediments as proxies of climate, environmental and sea-level change, tectonic activity, and the age of archaeological sites. Thorough reviews of luminescence applications to fluvial sediments and the typical problems encountered in doing so are provided by Wallinga , Jain et al.