The most widespread eolian deposits of the Victoria Land dry valleys, Antarctica, are pebble ripples which appear to b" of larger size than those r,eported from other continents. The crests of the ripples are composed of grains with a greater diameter than the grains of the flanks. The mean ripple index of 23 is higher than that of large ripples reported from outside Antarctica, and there does not seem to be a simple relationship between index and grain size. The high winds and high·density cold air of Antarctica appear capable of moving the largest pebbles which have a diameter of 19 mm.Sand forming transverse and whaleback dunes in the Victoria Valley is derived from the outwash from the Victoria Lower Glacier. The sand in the dunes is interbedded with snow, and moisture from this allows the dunes to be permafrosted except for a thin surface layer of dry mobile sand. The mobile sands of the transverse dunes are seasonally reversing. The sands of the dunes are well sorted and there is no selectiv5 deposition of a particular grain size in any area of the dunes. A characteristically granule-size lag deposit occurs on some interdune areas, and on the wha1ehack dunes, where it controls the size of the ripples. The granules may be in the critical size range for stabilising ripples which move only during infrequent very high velocity winds.

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Spatially discontinuous meltwater channel networks on the Canadian Prairies are usually interpreted as having formed subaerially in front of the retreating Laurentide ice sheet. Evidence in the Coronation–Spondin scabland, east-central Alberta, supports an alternative formation by progressive channelization of a subglacial sheetflow of water. The scabland is an integrated channel network with varying degrees of anabranching, the channels having highly variable sizes, shapes, and orientations. Enhanced scour at some channel confluences reflects contemporaneous channel utilization. Channels also display convex-up, concave-up, and undulatory along-channel profiles, with some junctions at the same elevations. Longitudinal grooves in large-scale channels are associated with numerous boulder deposits. Residual hills, demarcated by channels, display composite and streamlined forms. Superimposed on residuals are erosional transverse bedforms, longitudinal grooves, and undulating surfaces that indicate submergence for all but the last phase of channelization. Glaciofluvial deposits are found as pendant bars on the distal end of some large, flat-topped residuals, or as mantles superimposed on some residuals. The scabland is interpreted to have formed as a waning, subglacial sheetflood diverted around hummocky terrain to the southwest. A rapidly subsiding ice roof, and instability in the flow, eventually concentrated meltwater into discrete channels. Abrupt cessation of flow left discontinuous gravel–boulder deposits, and ice sheet loading formed small-scale glaciotectonic features as the ice recoupled to its bed. Subsequent deglaciation barely modified the scabland, leaving it straddling part of the modern topographic divide between the Battle and Red Deer river basins.

Contemporary processes of moraine development at the margins of polar glaciers encompass a wide range of subtly different mechanisms. Two types of “controlled” moraine evolution, applicable to hummocks and transverse moraine ridges, are identified from Wright Lower Glacier and Webb Glacier, southern Victoria Land, Antarctica. Type 1 moraine complexes involve a relatively abundant supply of supraglacial debris, the development of transverse thrust blocks in the ablation-zone ice and the subsequent re-arrangement of ablation debris in ablation cusps and on inactive thrust blocks. Relict landform suites, apparently formed in this manner, reveal large coarse-grained hummocks inset behind moraine ridge remnants.Type 2 moraines may develop where the supply of supraglacial debris is meagre but the growth of ablation cusps concentrates primarily englacial debris into small irregular hummocks. The gravel component of this debris is usually of finer texture than for type 1 deposits, reflecting abrasion/attrition effects of prior englacial transportation. Transverse moraine ridges may or may not be associated with type 2 hummocks, depending on local variations of ice motion, ice decay, and debris supply.