| Article ID | Journal | Published Year | Pages | File Type |
|---|---|---|---|---|
| 4725100 | Quaternary Geochronology | 2012 | 6 Pages |
The loess deposits surrounding the high mountainous regions of Central Asia play an important role in understanding environmental changes in Eurasia on orbital and sub-orbital timescales. However, problems with dating Central Asian loess have limited the interpretation of climatic and environmental data, especially on sub-orbital timescales. We selected a controversial loess section, Zeketai (ZKT, with a thickness of 23 m), in the Yili basin in Xinjiang Province in western China, to establish a detailed and systematic Optically Stimulated Luminescence (OSL) chronology. Quartz grains of 38–63 μm were isolated from 15 samples and the single-aliquot regenerative-dose (SAR) protocol was employed for De determination. OSL ages are in stratigraphic order and range from 13.8 ± 1 to 72 ± 6 ka, suggesting continuous loess accumulation during the last glaciation. We compared these dating results with that of the previously published fine-grain sized quartz (4–11 μm) using simplified multiple aliquot regenerative-dose (SMAR) protocol, and with the previous published radiocarbon dating (14C) ages on snail shells. With the exception of three young samples from the upper 6 m of the section, the SMAR dating results are basically consistent with the results using the SAR protocol. Both the SMAR and SAR OSL ages are consistently older than the 14C ages, and the radiocarbon date results should be used with caution since they appear to have been underestimated.
► OSL chronology is established for loess section Zeketai in Xinjiang, western China. ► 15 quartz OSL ages are in stratigraphic order, and range from 14 to 72 ka. ► Loess accumulation is continuous from the bottom to the top with a thickness of 23 m. ► OSL age is compared with previous 14C age; the latter is severely underestimated.
