The analysis of the glacial landscape of southern Saskatchewan (Canada) through multiple data sets (e.g. digital elevation model, till compositional data) has revealed previously unrecognized subglacial sediment–landform assemblages. A southwest‐trending corridor of mega‐scale till lineations (Maskwa corridor) bounded on each side by hummocky terrain extends from the Canadian Shield to southwestern Saskatchewan. This landform assemblage is clearly cross‐cut by a broad south to southeast trending corridor (Buffalo corridor) consisting of subparallel curvilinear till ridges. The carbonate content of the surface till is spatially consistent within these assemblages, suggesting a strong sediment–landform relationship. The two corridors are interpreted as the product of palaeo‐ice streams. The Maskwa palaeo‐ice stream flowed up the regional slope and across preglacial valleys, indicating it was thick and stable. Narrow dispersal trains extending across as well as down‐glacier from the Athabasca Basin suggest that the Maskwa palaeo‐ice stream extended far into the ice sheet across contrasting shield and platform terrains. In comparison, the Buffalo palaeo‐ice stream was thinner and largely controlled by subglacial geology and topography. Its catchments were located at the Canadian Shield boundary and the system was oriented along‐slope. It experienced lateral shifts and it was fed by a network of tributaries. The glacial dynamics shift from the Maskwa to the Buffalo system occurred at about 13.5 14C kyr BP. The Buffalo system later evolved into thin outlet lobes until final deglaciation of the area. The proposed model has implications for ice‐sheet reconstruction and the assessment of till properties in the prairies and in similar terrains.

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Champlain Sea history is directly linked to Late Wisconsinan deglacial episodes. Champlain Sea Phase I (Charlesbourg Phase) began in the Québec area at about 12.4 ka. It represented a western extension of the Goldthwait Sea between remnant Appalachian ice masses and the Laurentide Ice Sheet. Further south, at about the same time, in the Appalachian uplands and piedmont, high-level glacial lakes were impounded by the ice-front during glacial retreat toward NNW: lakes Vermont, Memphrémagog and Mégantic. Lowlands of the Upper St. Lawrence and Lake Champlain valleys were progressively deglaciated and inundated by Lake Iroquois and Lake Vermont. At about 12.1 ka, these two lakes coalesced and formed a single water-body, here referred to as Lake Candona. After the Ulverton-Tingwick Moraine was constructed, this lake extended northeastward onto the Appalachian piedmont where varved sediments containing Candona subtriangulata underlie marine clays. Current data and interpretations bring into question the former concept of the Highland Front Moraine System. The invasion of the main basin, or Champlain Sea Phase II, began around 12 ka. Replacement of Lake Candona by the sea resulted in a fall of about 60 m in water levels. Champlain Sea Phase III began at the end of the Saint-Narcisse episode, at about 10.8 ka. At this time marine waters were able to enter valleys of the Laurentian Highlands where brackish or fresh paramarine basins developed.L'histoire de la Mer de Champlain est directement liée à la déglaciation du Wisconsinien supérieur. La phase I de la Mer de Champlain (Phase de Charlesbourg) débute dans la région de Québec vers 12,4 ka. Elle représente le prolongement de la Mer de Goldthwait entre l'Inlandsis laurentidien et les glaces résiduelles appalachiennes. Plus au sud et approximativement en même temps, le retrait glaciaire vers le NNW sur les plateaux et le piémont appalachiens est marqué par des moraines et les lacs proglaciaires Vermont, Memphrémagog et Mégantic; les terres basses du haut Saint-Laurent et du lac Champlain étaient progressivement déglacées et inondées par les lacs Iroquois et Vermont. Vers 12,1 ka, ces deux lacs forment par coalescence Ie Lac Candona. Après l'épisode de la Moraine d'Ulverton-Tingwick, ce lac inondait le piémont appalachien vers le NE, où des varves à Candona subtriangulata reposent sous les argiles marines. Ces données remettent en question le concept de Highland Front Moraine System. L'invasion du bassin principal (Phase II de la Mer de Champlain) débute vers 12 ka. Le remplacement du Lac Candona par la mer provoque une chute d'environ 60 m du niveau du plan d'eau. La Phase III de la Mer de Champlain commence à la fin de l'épisode de Saint-Narcisse, vers 10,8 ka; les eaux marines pénètrent dans les vallées des Laurentides et sont coalescentes à des bassins paramarins saumâtres ou non salés.Die Geschichte des Meeres von Champlain ist direkt mit Enteisungs-Episoden im spàten Wisconsin verknùpft. Die Phase I des Champlains-Meeres (Charlesbourg Phase) began im Gebiet von Québec...

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In view of the high reactivity of the lithium metal, lithium batteries must operate in an aprotic environment, which can either be a conducting polymer; a liquid solvent, or a mixture of them. Two families of aprotic liquids were considered as solvents for lithium bis(trifluoromethylsulfone)imide (LiCF3SO2NSO2CF3 or LiTFSI). The first one is the substituted sulfamides, R1R2NSO2NR3R4, where the R groups are either methyl, ethyl, or methoxyethyl (CH,CHOOCH,), and the second one is the glymes, CH3O(CH2CH3O)CH3, for n up to 10. The phase diagrams, potential windows, conductivities, and the lithium interfacial resistances of the solutions were investigated, often as a function of temperature. The potential use of these solvents for different types of batteries is discussed.* Electrochemical Society Active Member. * * Electrochemical Society Student Member.making the molecule unsymmetrical and more polar, i.e., by replacing the ethyl groups by methyl or methoxyethyl groups, i.e., CH3CH2OCH3. The present paper deals with the phase diagrams, conductivities, potential windows, and lithium interfacial resistances of LiTFSI in these substituted sulfamides. The synthesis and properties of these liquid sulfamides is described elsewhere.'6 The use of these sulfamides as diluents for a polymer electrolyte is reported elsewhere.'7 The sulfamides used in this investigation are summarized in Table I where a short abbreviation is given for each.Another family of aprotic liquids which has proven interesting as solvents for high-energy batteries is the glymes18 or (polyethyleneglycol) dimethylether, CH,O(CH2CH,O)CH3.Unfortunately, the first member of the series, also called Sulfamtdes Rl\ '1? 1R,