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Luminescence dating of aeolian sands: an overview

1993; Geological Society of London; Volume: 72; Issue: 1 Linguagem: Inglês

10.1144/gsl.sp.1993.072.01.06

2041-4927

A.G. Wintle,

Planetary Science and Exploration

Abstract Aeolian sands are ideal materials for the application of luminescence techniques. Their primary mineral constituents, quartz and feldspars, exhibit a variety of luminescence properties and can be separated for mineral-specific measurements. Individual grains are usually well exposed to light prior to deposition thus enabling their signal to be zeroed at the time of interest. Luminescence is produced either by heating the grains to produce thermoluminescence (TL) or by stimulating at room temperature with wavelengths specific for each mineral component. Only light-sensitive signals are observed in measurements of optically stimulated luminescence (OSL). For feldspars, infra-red stimulated luminescence (IRSL) can be obtained using IR-emitting diodes. Luminescence dating techniques can be applied to inland sand seas, small dunefields, coastal dune systems or periglacial sand sheets. Natural variation in radioactive content in different geographical areas can be used to advantage — sands with a high radioactive content, as found in areas dominated by granitic rocks, are best suited for applications to Holocene dunefields (such as Kelso, California), whereas sands with a low radioactive content, as found in areas containing little feldspar-bearing rock and with much recycled sediment (e.g. Australia), are best suited to applications spanning the last 100 ka.