Rapid And Cyclic Dust Accumulation During MIS 2 In Central Asia Inferred From Loess OSL Dating And Grain-size Analysis Scientific Reports

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Apr 1, 2023

During the early Holocene, a warm and wet climate has been widely reported from the lake sediments (Wei and Gasse, 1999; Wu et al., 2006) and ice-core records (Thompson et al., 1989) on the TP. Previous studies on lake shorelines in the TP also show high lake levels during this period (e.g. Pan et al., 2012; Chen et al., 2013; Hudson et al., 2015). The ∼10–7 ka shoreline in Siling Co indicates that this lake also achieved a high lake level in the early Holocene, which is consistent with the environment and climate change during this time. Compared with the extremely cold climate during the Last Glacial period, the warm and wet climate in the Holocene provided favorable conditions for ancient human activities, encouraging their expansion and occupation. Figure 1.Examples of isothermal TA-OSL curves from BeO discs for four different measurement temperatures ; the inset presents a TL before and an RTL glow curve after TA-OSL at 190 °C. Intense TA-OSL signal is measured for all stimulation temperatures.

These results are also presented in Figure 7 as open data points for both TL peaks. Insignificant sensitivity changes are monitored for doses as large as 1–5 Gy. For larger doses, mild sensitization is prominent for both TL peaks. This sensitization is dose-dependent, indicating an increasing trend with dose. This change in the TL sensitivity is larger in the absence of the TA-OSL measurement for both TL peaks. Moreover, between these two, sensitization is always larger for TL peak 2.

TL 30, 1–8 . Olley, J. M., Murray, A. S. & Roberts, R. G. The effects of disequilibria in the uranium and thorium decay chains on burial dose rates in fluvial sediments.

& Roberts, R. G. The origin of dose distributions in fluvial sediments, and the prospect of dating single grains from fluvial deposits using optically stimulated luminescence. 30, 207–217 . Combès, B. A Bayesian central equivalent dose model for optically stimulated luminescence dating. 28, 62–70 .

1 Luminescence

Dating recent floodplain sediments in the Hawkesbury–Nepean River system, eastern Australia using single-grain quartz OSL. Boreas 43, 1–21 . Arnold, L. J. & Demuro, https://hookupinsight.com/friendfinder-review/ M. Insights into TT-OSL signal stability from single-grain analyses of known-age deposits at Atapuerca, Spain. 30, 472–478 . Thomsen, K. J., Murray, A.

Selection of integration time intervals for quartz OSL decay curves

Murray, A. S. & Olley, J. M. Precision and accuracy in the optically stimulated luminescence dating of sedimentary quartz. Geochronometria 21, 1–16 .

In our 2015–2017 fieldwork, an assemblage of 36 stone artifacts, including 15 flakes, 17 tools, and four micro-cores, were spotted on the surface of the ∼4,600 m paleo-shoreline in southeastern Siling Co . The artifacts are mostly made of dark grey slate, and the raw materials could be readily found in surrounding areas. Surfaces and edges of the artifacts show little signs of erosion or rounding, suggesting that they were not transported from elsewhere. The allogenic possibility is further ruled out by the absence of higher paleo-shorelines around the site.

Change 162, 84–100 . Demuro, M., Arnold, L. J., Parés, J. M. & Sala, R. Extended-range luminescence chronologies suggest potentially complex bone accumulation histories at the Early-to-Middle Pleistocene palaeontological site of Huéscar-1 (Guadix-Baza basin, Spain). 389, 191–212 . Kale, V. S., Singhvi, A. K., Mishra, P. K.

Dose Rate Measurement

Our speculation is consistent with previous research indicating that the lake level of Zhari Namco declined by 42.5 m between 3.9 and 2.0 ka BP (from 4,680.6 to 4,637.9 m) (Chen et al., 2013). The OSL lab is recognised as one of the world’s leading archaeological dating laboratories, based on its track record of using OSL dating to answer internationally significant questions in archaeology and palaeoanthropology. In the Aberystwyth Luminescence Laboratory our instruments are made by a Danish manufacturer and are called “Risø OSL/TL readers”. We measure this emitted light and this is the first stage towards measuring the sample age. But what is optically stimulated luminescence , other than a mouthful? Basically, it can help archaeologists figure out when things were buried by calculating the time that has passed since grains of quartz sand were last exposed to light.

& Thomas, D. S. G. Rates of dust deposition between 50 ka and 20 ka revealed by OSL dating at Yuanbao on the Chinese Loess Plateau. Palaeogeography, Palaeoclimatology, Palaeoecology 248, 431–439 . ZL organized the project. ZL, LY, and CH collected the OSL samples. WZ and CH conducted the experiments in the laboratory. LL and ZL performed data analysis.

The quartz captures electrons from this radiation; the radiation flow is called the dose rate. This is like the steady ticking of a clock. The quartz begins trapping electrons, and because it is cut off from light, the trapped electrons will continue building up at a fairly steady, measurable rate.