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Victoria University Antarctic Research Expedition Science and Logistics Reports 1975-76: VUWAE 20

B. Late Cenozoic Stratigraphy — Part 1

B. Late Cenozoic Stratigraphy
Part 1

  1. Beds of till are ubiquituous throughout the upper Taylor Valley, although exposure is poor except around the snout of the Taylor Glacier. Here meltwater streams from the Rhone and Calkin Glaciers have cut through till sequences on both sides of the valley. These till outcrops have been described, sampled and measured for pebble fabrics.

    Correlation of till deposits throughout the upper valley will be attempted, using grain size analysis, pebble orientation, mineralogy, sedimentary structures etc. From observations of depositional processes occurring around the Taylor Glacier snout at present this correlation could be difficult, for it appears that deposition of till as sheets is quite rare. In fact the glacial drift can change in character from till to mudflow to fluvial sediments over short distances from the ice front, thus limiting the extent of correlation.

    The presence of till sheets in parts of the valley contrasts with the recent deposits, suggesting that modes of deposition from Taylor Glacier ice have changed with time. Processes of entrainment, transport and deposition of debris, were analysed in an attempt to set up the Taylor Glacier as a model for glacial drift deposition.

    This model was extended to include proglacial, glaciofluvial, glacio-lacustrine and aeolian environments by observation of recent sediment deposition in the Wright Valley and at Cape Chocolate.

  2. The Wright Lower Glacier shows signs of active ice ablation from the snout where coarse, angular and moderately sorted ablation till is accumulating. Sand blown by wind on to the glacier is being washed off and concentrated around the snout due to meltwater action.page 7
  3. An ice-dammed proglacial lake was probably responsible for the deposition of the stratified fluvial sediments within the terraces at Cape Chocolate, while the surrounding moraines are probably from an enlarged Koettlitz Glacier or Ross Ice Shelf.