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In northern Nunavik, orientation of ice-flow features and dispersal patterns of lithologic indicators suggest three major regional ice-flow phases. The oldest ice-flow phase is related to the buildup of an outflow centre, the Ungava centre, over the high plateaux located north of the Povungnituk Hills. During that event, probably of Early Wisconsinan age, ice flows towards the south and southeast carried Cape Smith Belt rock fragments over a maximum distance of 65 km. The second phase is characterized by ice flow mainly towards the north from an outflow ice centre located south of the studied area (Payne centre). The most recent ice-flow phase is related to the presence of the northern extension of the New-Quebec ice divide. From that northwest-trending ice divide extending between Ivujivik and Lake Nantais, ice was flowing outward on the peninsula. The orientation of most of the ice-flow features and dispersal patterns is associated with that last ice flow. North of the Cape Smith Belt, glacial transport was at least 70 km. In Hudson Strait, ice-flow and glacial transport data support the existence of an eastward flowing ice stream. [ABSTRACT FROM AUTHOR]

Two Woodfordian glaciated regions in Wisconsin were analyzed to determine the impact of variable loess thickness and contrasting till texture on soil pattern and landscape properties. Each region consisted of a ground moraine/end moraine/outwash plain landform sequence. Data were compiled from soil and topographic maps. In addition to using standard methods of soilscape analysis. I used a natural soil drainage index, calculated from taxonomic data, to determine regional variability and pattern of soil wetness. Results indicate that soilscape variation within each region was large. There were no statistically significant differences, therefore, that could be attributed to known soil- forming processes or to parent material variability. Stratifying the data by geomorphic subregion rather than by region reduced the within-unit soil variability and resulted in numerous significant soilscape differences between subregions. The implication is that soilscape variability is large at the regional scale but converges rapidly with decreasing size of study area. [ABSTRACT FROM AUTHOR]

Measurements of discharge, reach morphology, and cross-section morphology in supraglacial streams on the Juneau Icefield reveal controlling variables that have analogous counterparts in alluvial streams. Downward sky radiation imparts a strong diurnal pattern to supraglacial runoff generated by saturated slush flows, precipitation and melting, channel erosion, and spillover from water-filled moulins, crevasses, and supraglacial lakes. Supraglacial streams are generated when runoff is concentrated on glacier slopes and rates of incision exceed rates of glacier surface ablation. Streams leave the surface via moulins and crevasses where the water becomes part of the englacial and subglacial drainage systems. Meander systems develop and migrate downstream, driven by thermal erosion with heat supplied by climatic and hydrologic sources. Sinuosity attains a maximum value, in the absence of other roughness factors, when high stream power is imposed from an adjacent upstream reach. Form-process relationships for supraglacial meanders are similar to those for alluvial streams in spite of the contrast in time and scale of development. At-a-station hydraulic geometry for supraglacial streams serves to identify channel adjustments to changing discharge not unlike those for narrow-deep, straight alluvial streams. Daily formation of longitudinal grooves in channel walls leaves a record of daily flow and yields critical information regarding channel enlargement ratios. Fluvial adjustment toward equilibrium conditions involves all elements of channel roughness and cannot be analyzed using any single indicator such as channel pattern, cross-sectional shape, or materials involved. [ABSTRACT FROM AUTHOR]