Sediment cores form Breid Bay and Brekilen, antarctica
Eisma, D. (1973). Sediment cores form Breid Bay and Brekilen, antarctica. Neth. J. Sea Res. 6(3): 327-338
In: Netherlands Journal of Sea Research. Netherlands Institute for Sea Research (NIOZ): Groningen; Den Burg. ISSN 0077-7579; e-ISSN 1873-1406, meer
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| Abstract |
A number of cores from the Antarctic continental shelf at Breid Bay, Queen Maud Land, were analysed for grain size, mineralogy, organic matter, carbonate, silica, phosphate, sulphate and a number of trace metals. Most core samples are poorly sorted, containing gravel as well as fine silt, and can be regarded as deposited by ice. Small coarse sandy layers, however, point to deposition by currents. The composition of most cores (high percentages of feldspar, mica, clean angular and subrounded grains and rock fragments, and no clay minerals) agrees with the predominantly mechanical weathering in Antarctica, whereas weathered heavy minerals in some cores and the reddish-grey montmorillonitic sediment in one of the cores point to reworking of older material. Two cores contain large amounts of organic silica. Carbonate, organic matter and phosphate contents are low, and no sulphate was found. The trace element composition shows a change at 10 to 20 or 40 to 50 cm depth in the cores. If this is related to change in ice-flow pattern and if this is assumed to be correlated with the end of the Pleistocene, deposition rates during the Holocene are in the order of 10 to 50 mm per 1000 years, which is in good agreement with rates given by others. |
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