26Al/10Be dating of an aeolian dust mantle soil in western New South Wales, Australia

Fisher, Adrian, Fink, David, Chappell, John and Melville, Michael (2014) 26Al/10Be dating of an aeolian dust mantle soil in western New South Wales, Australia. Geomorphology, 219 201-212. doi:10.1016/j.geomorph.2014.05.007

Author Fisher, Adrian
Fink, David
Chappell, John
Melville, Michael
Title 26Al/10Be dating of an aeolian dust mantle soil in western New South Wales, Australia
Formatted title
26Al/10Be dating of an aeolian dust mantle soil in western New South Wales, Australia
Journal name Geomorphology   Check publisher's open access policy
ISSN 0169-555X
Publication date 2014-08-15
Sub-type Article (original research)
DOI 10.1016/j.geomorph.2014.05.007
Open Access Status Not Open Access
Volume 219
Start page 201
End page 212
Total pages 12
Place of publication Amsterdam, Netherlands
Publisher Elsevier
Language eng
Formatted abstract
Aeolian dust mantle soils are an important element of many landscapes in south-eastern Australia, though the age of these aeolian deposits has not been radiometrically determined. At Fowlers Gap in western New South Wales, surface cobbles of silcrete and quartz overlie a stone-free, aeolian dust mantle soil, which has a thickness of about 1.6m. The clay-rich aeolian dust deposit in turn lies upon a buried silcrete and quartz stone layer. Modelling in-situ cosmogenic 26Al and 10Be concentrations measured in both the surface quartz stones and in the buried quartz layer of rocks, reveals that each has experienced a complex exposure-burial history. Due to the absence of quartz stones or sand at intermediate depths, our cosmogenic 26Al and 10Be modelling was not able to determine a definitive mechanism of stone pavement formation and stone burial. Various scenarios of stone formation, transport, burial and exhumation were tested that constrain the age of the deposit to range from 0.9±0.2Ma to 1.8±0.2Ma, based largely on different assumptions taken for the time-dependency of the net sedimentation rate. This corresponds with the initiation of the Simpson Desert dune fields and the deflation of lakes in central Australia, which probably responded to the shift to longer-wavelength, larger-amplitude Quaternary glacial cycles at around 1Ma. Sensitivity analyses were carried out to identify those parameters which better constrained model outputs. Within model errors, which largely are the result of analytical errors in measured 26Al and 10Be concentrations, all three competing theories of colluvial wash, upward displacement of stones, and cumulic pedogenesis are possible mechanisms for the formation of the surface stone pavement.
Keyword Cosmogenic nuclides
Aeolian dust
Stony deserts
Quaternary palaeoclimate
Q-Index Code C1
Q-Index Status Provisional Code
Institutional Status Non-UQ

Document type: Journal Article
Sub-type: Article (original research)
Collection: School of Geography, Planning and Environmental Management Publications
Version Filter Type
Citation counts: TR Web of Science Citation Count  Cited 1 times in Thomson Reuters Web of Science Article | Citations
Scopus Citation Count Cited 3 times in Scopus Article | Citations
Google Scholar Search Google Scholar
Created: Wed, 06 Apr 2016, 09:18:03 EST by Adrian Fisher on behalf of School of Geography, Planning & Env Management