Titre | Luminescence dating of aeolian sand from the Northern Great Plains, Canada - the utility of feldspar and quartz for providing temporal control on postglacial environmental change |
Auteur | Lian, O; Cullen, J; Wolfe, S |
Source | 2010 p. 147 (Accès ouvert) |
Liens | Online - En ligne
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Année | 2010 |
Séries alt. | Secteur des sciences de la Terre, Contribution externe 20090465 |
Réunion | Prairie Summit CAG-CGRG Annual Meeting; Regina, SK; CA; juin 1-5, 2010 |
Document | livre |
Lang. | anglais |
Media | en ligne; numérique |
Formats | html |
Province | Alberta; Manitoba; Saskatchewan |
Région | Great Plains |
Sujets | dépôts éoliens; dunes; sables; quartz; sédimentologie; géochronologie; Nature et environnement |
Programme | Géosciences de changements climatiques, Études paléo-environnementales sur les changements climatiques |
Résumé | (disponible en anglais seulement) Over the past 15 years more than 100 luminescence ages have been calculated from feldspar and quartz grains extracted from sand dunes on the Northern Great
Plains, Canada. The vast majority of these ages have come from feldspar, and they range from a few decades to more than 15,000 years. Feldspar ages have traditionally been calculated using multiple-aliquot techniques where it is assumed that all of
the grains sampled have been exposed to sufficient sunlight prior to burial. Although these techniques are, in most cases, well-suited to the aeolian depositional environments of interest, the luminescence signal from feldspar suffers from anomalous
fading, and this requires that relatively complex laboratory measurements be made in order to correct for its effect. Quartz, on the other hand, would appear to be a more suitable as the luminescence signal from it resets much more quickly than that
from feldspar, and it does not suffer from anomalous fading. Moreover, the latest single-aliquot regenerative (SAR) protocols can be applied to quartz, whereas they are not generally applicable to feldspar. The SAR technique is simple and less
laborious, and it easily allows for the discrimination of age populations in a sample. Despite the favourable characteristics of quartz we have found instances where it, and standard SAR protocols, appear to be unsuitable. In this paper we illustrate
the utility of using quartz and feldspar to dating sand dune evolution on the Great Northern Plains, and we provide recommendations for estimating the fidelity of luminescence ages from this region. |
GEOSCAN ID | 262717 |
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