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Abstract: The thermoluminescence (TL) and optically stimulated luminescence (OSL) sensitivities of quartz grains from deserts and loess–red clay sequences are used to trace eolian provenances in northern China. Our results indicate that the 110°C TL peak and OSL sensitivities of quartz grains show differences among Chinese deserts, which can be subdivided into four groups according to the spatial variations of luminescence sensitivities. Such differences are related mostly to the regional difference in rock types of mountains surrounding or adjacent to the deserts. We also examine the possible provenance changes between the Quaternary loess and the Tertiary eolian red clay, and the results indicate that the luminescence sensitivity of Tertiary red clay is higher than that of Quaternary loess (L1, L15, and L33), implying source materials of the eolian deposits changed relative to those of the Quaternary. [Copyright &y& Elsevier]

Abstract: Three-dimensional thermoluminescence spectra are measured for different types of geological origin quartz from the Altay orogenic belt, northern Xinjiang, China. The results show striking differences which appear to be characteristic of their geological origin. Granitic quartz is dominated by emission bands at 420–430nm, 550–560nm, at a temperature of 170°C. Pegmatite quartz is characterized by an intense 480nm emission band at 170°C. Volcanic quartz has exclusive UV (340–360nm) and violet (410–430nm) emission bands. Hydrothermal quartz exhibits very different TL spectral characteristics because of different hydrothermal activity and mineralization. Only one TL peaks at 485nm/170°C was observed in sedimentary quartz. An intense 730nm emission band observed at 170°C considered generally to be characteristics of feldspar was observed in quartz from granite and hydrothermal Au-bearing quartz. This TL peak is probably related to the centre of [FeO4]0 on an Si site. All samples show an intense 990–1000nm emission band at 330°C. Identical types of quartz formed in different regions or different geological and tectonic settings can also exhibit striking differences in TL spectra. [Copyright &y& Elsevier]