Three soil chronosequences in recessional glacial deposits n
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TitleThree soil chronosequences in recessional glacial deposits near the polar plateau, in the Central Transantarctic Mountains, AntarcticaAbstractSoil chronosequences in till deposits emplaced during glacial retreat in the Central Transantarctic Mountains are described. Discrepancies between the degree of soil development and reported cosmogenic surface exposure ages suggest slower, weaker soil development in this region than encountered in other areas of Antarctica. The study sites (Dominion Range, Mount Achernar and Ong Valley) were located between 83^circ and 85^circS, at altitudes of 1600-2200 m, on the edge of the polar plateau. Soil landscape maps show a gradation of soil properties across landscape units that were designated as homogenous/single- event drifts in previous smaller-scale studies. Along transects away from the current ice edge, the depth to underlying ice thickened (from 2 cm to > 80 cm), soil became more weathered, saltier and less alkaline, and horizonation became more pronounced. Soil thickness, clast abundance and soil chemistry are all consistent with a two-layer mode of soil formation. We suggest that a thin, clast-rich surface horizon, originating from weathering of supraglacial debris, overlies a thick, clast-poor sublimation till. The supraglacial debris has a finite contribution to soil volume, whereas sublimation offers an ongoing source of soil material that thickens the soil from its base. â"' Antarctic Science Ltd 2014.AcknowledgementsThe authors thank Landcare Research (specifically Jackie Aislabie) for funding of both fieldwork and lab analyses (Ministry of Business, Innovation and Employment; grant #CO9X1001). The United States Antarctic Research Program (USAP) via the Polar Geospatial Centre, University of Minnesota, provided satellite imagery and maps. Thanks to Errol Balks for field and technical assistance, and Malcolm McLeod and Glen Stichbury for mapping assistance. Logistical support was provided by Antarctica New Zealand and USAP (especially staff at the CTAM field camp). The thorough review by M McLeod and W Dickinson greatly improved this paper.
TypeArticleCitationScarrow, J., Balks, M. and Almond, P. (2014) Three soil chronosequences in recessional glacial deposits near the polar plateau, in the Central Transantarctic Mountains, Antarctica. Antarctic Science, 26(5): 573-583 doi:10.1017/S0954102014000078
Antarctica NZ (26th Nov 2018). Three soil chronosequences in recessional glacial deposits n. In Website Antarctica NZ. Retrieved 30th Nov 2021 15:53, from https://adam.antarcticanz.govt.nz/nodes/view/63754