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ABSTRACTDetailed facies mapping along Lake Erie and Lake Ontario Bluffs, plus other studies illustrate that sedimentological studies, especially those with geomorphic or landform control, have had three main effects on the Wisconsinan stratigraphy of Ontario: (1) improved understanding of depositional processes and environments of several major rock stratigraphic units, without altering the stratigraphic framework, (2) aided correlation of drift sequences, and (3) questioned previous interpretations and stratigraphic correlations of drift sequences. Thus sedimentological analysis can not be separated from stratigraphy because the interpretation of depositional environnments of many mapped strata relies on their geometry and the inclusion of regional data. The geomorphic control provided by sedimentological study of surface landforms is also important because assessment of older buried sediments such as those at the Scarborough Bluffs has been hampered by the failure to determine landform control. The Late Wisconsinan stratigraphy of Southern Ontario generally remains unchanged, except for questions on the role of climate versus ice margin dynamics. The pre-Late Wisconsinan stratigraphy is scarce and not well defined, yet sedimentary studies support the presence of glacial ice in the Ontario Lake basin for all of the Middle Wisconsinan and possibly earlier, including the formation of the Scarborough delta. Large channel cut and fill sequences in the Toronto area (Pottery Road Formation), initially interpreted as resulting from subaerial erosion, were probably formed by subaqueous or subglacial meltwater erosion. If so, the pre-Late Wisconsinan stratigraphy in southern Ontario changes because the Pottery Road Formation may not be an Early Wisconsinan correlative of the St. Pierre beds. The channel example illustrates that stratigraphie correlation without sedimentological investigations may be misleading.

ABSTRACTSediment cores, taken at depths of 140 to 300 m across the northwestern shelf of Axel Heiberg Island (82° N), record the deposition of sediments under perennial sea ice. Five sedimentary fades are recognized: (A) soft pebbly-sandy-mud with dropstone structures; (B) bioturbated silty muds; (C) wispy-laminated silty clay/clay; (D) laminated sands/silts and mud; (E) firm pebbly-sandy-mud with chaotic pebble fabrics. Other sediments include terrestrial bedrock of Paleogene Eureka Sound Group, and a younger Tertiary deposit, possibly the Beaufort Formation. Ages range from 1530 ± 60 BP (Fades A) to 9950 ± 80 BP (Fades D). Sedimentation rates vary as follows: - 0.8 cm ka-1, Fades B; 4 cm ka"\ Fades A; 90 cm ka-1, Fades C; 134 cm ka~', Fades D. The sedimentation history, as interpreted from the sedimentology, palynology and foraminiferal results, suggests intervals of more continuous ice cover, with a reduced influx of coarse ice-rafted detritus, alternating with more open water conditions, and high sediment input from meltwater and/or floating icebergs. Only marine sediments overlie Neogene bedrock in the cores. The absence of diamictons at the core sites suggests that grounded ice perhaps never occupied this part of the Axel Heiberg Island shelf. The interpreted history of sedimentation generally corresponds to the land-based record from Ellesmere Island, but differs significantly from marine-based studies in more southern latitudes.

This article focuses on biliteracy among bi/multilingual students in a Quebec context, particularly those from minority or minoritized language groups. We emphasize the importance of taking into account the biliteracy abilities of allophone students in the teaching practice, especially regarding their effects on the teaching-learning of the language. The interest is to shed light on the understanding that education stakeholders may have biliteracy, particularly those working in a bi/multilingual environment, and to bring out new lines of questioning. First is the question of literacy, a complex and variable concept that is currently undergoing a major conceptual expansion, reflecting a diversity of positions among researchers. We then look at biliteracy, which we consider from the angle of a non-dichotomous concept regarding abilities in bi/pluraliteracy. This very complex concept seems very little mobilized in Quebec. However, it raises important didactical issues, in particular the transfer of knowledge and literacy skills from one language to another, as well as the place occupied by the linguistic and cultural resources of bi/multilingual students in the classroom. In perspective, we briefly explore an operational framework for studying biliteracy in schools.

ABSTRACTCordilleran Ice Sheet glaciations show characteristic patterns of advance and retreat, consisting of (1) advance out outwash, (2) glacial scouring, (3) deposition of till, (4) deposition of recessional outwash south of Seattle in the southern Puget Lowland, glaciomarine drift in the northern lowland, and eskers, kames, and small moraines on the Columbia Plateau. Radiocarbon dates show that the Puget and Juan de Fuca lobes advanced and retreated synchronously. The Puget lobe backwasted to Seattle by 13.4-14 ka yrs BP, where the thinning ice floated in seawater northward to Canada by 13 ka yrs BP depositing glaciomarine drift contemporaneously over 18,000 km2. Compelling evidence against the backwasting, calving, terminus model for the origin of the glaciomarine drift includes: 1) abundant 14C dates demonstrate simultaneous deposition of glaciomarine drift over the entire area; 2) stagnant-ice deposits closely related to glaciomarine drift are not consistent with an actively-calving, backwasting terminus; 3) irrefutable evidence for the nonmarine origin of Deming sand shows that Cordilleran ice was absent immediately prior to deposition of the overlying glaciomarine drift. The pattern of events in the northern Puget Lowland includes: 1) glacial loading under 1800 m of ice during the Vashon maximum; 2) rapid glacial thinning and floating of the ice deposited Kulshan glaciomarine drift 12-13 ka yrs BP; 3) emergence and deposition of fluvial Deming sand 11.5 ka yrs BP; 4) resubmer-gence and deposition of Bellingham glaciomarine drift up to -200 m, well beyond global eustatic sea level rise; 5) emergence 10.5-11.5 ka yrs BP and deposition of Sumas outwash on Bellingham glaciomarine drift; 6) Holocene eustatic sea level rise kept pace with isostatic rebound, thus, post-Sumas marine terraces are absent.

Pollen analysis of the sediments of three lakes located southeast of the Laurentides provincial Park served to reconstruct different stages in the post-Wisconsinan vegetational history. Those stages proved to be widespread within the studied area. The first stage (subzone 1a) corresponds to a very open landscape, but the scarce vegetation cover already consisted in many herb and shrub taxa. After a transitional stage (subzone 1b), a very rich tundra-like vegetation occurred (subzone 1c), followed by a shrub-dominated vegetation in which Betula glandulosa played an important role (subzone 1d). Populus cf. tremuloïdes initiated the afforestation stage (subzone 2a), followed by Picea mariana. The afforestation was completed by the immigration of many tree species (Betula papyrifera, Pinus cf. divaricata, Abies balsamea, Picea glauca and Larix laricina) during the next stage (subzone 2b). The pollen of Alnus cf. crispa shows maximum abundance within subzone 2b. The dating of these stages is hampered by thp lack of chronological control of the largely inorganic sediments to which they belong. However, at least one thousand years passed between ice retreat and the immigration of Populus cf. tremuloïdes. The forest vegetation history (zone 3) that followed afforestation has been quite monotonous. Only minor changes of the abundance of species like Pinus strobus, Picea mariana and Pinus cf. divaricata are revealed by the pollen diagrams. Most of the tree species were present very early in the Holocene.

ABSTRACTEnhanced meltwater discharge from proglacial lakes Agassiz and Barlow-Ojibway at about 9.6 to 8.3 ka BP. created cold localized climates over downstream water bodies, specifically Lake Minong and Mattawa phase lakes in the Great Lakes and Goldthwait Sea in the Gulf of St. Lawrence. The cooling effect of the meltwater drainage suppressed summer warming of the surface lake waters, reduced the growing season and thus altered the vegetation composition in the surrounding land areas. The vegetation responded in different ways as evidenced by five variants from the normal pollen succession.The pollen anomalies are most pronounced where the effect of increased meltwater discharge had a strong influence, such as within or along the margins of Lake Agassiz, Mattawa phase lakes, and the Goldthwait Sea, or in their lee areas, especially where these water bodies intersected ecotonal boundaries. Climatic effects were minimal or non-existent where the water surface areas were restricted such as the channelized drainage routes of the Ottawa and St. Lawrence rivers. Diversion of Lakes Agassiz and Barlow-Ojibway drainage to Hudson Bay after about 8.4 ka BP reinstated summer warming of the surface water in the Great Lakes-St. Lawrence system bringing the 9.6-8.3 ka cool period to a close.

ABSTRACTThe regional distribution of Holocene sediments of eastern Hudson Bay off the Grande Rivière de la Baleine mouth was mapped using a grid of reflection seismic lines (approximately 300 km long and covering an area of approximately 800 km2) and data from 7 piston cores. Based on the seismic records and piston cores, 4 stratigraphic units overlying the Proterozoic bedrock (unit 1) were defined and interpreted: (unit 2) glacial till deposited by a westward flowing ice sheet, (unit 3) rhythmically bedded clays and silts presumably deposited in glacial Lake Ojibway, (unit 4) postglacial marine muds deposited in the Tyrrell Sea overlain by undifferentiated modern marine muds, and (unit 5) distal fluviodeltaic sediments from Grande Rivière de la Baleine. Similar stratigraphie units have been described onshore. Textural and geochemical analyses suggest that unit 3 rhythmites are true varves; dark "summer" laminae were deposited mainly by underflows during the open water season, and light "winter" laminae were deposited by overflows-interflows along thermal stratifications under a seasonal ice cover. Unit 5 covers approximately 400 km2 and occurs as a deltaic constructional wedge protruding as far as 11 km offshore of the Grande Rivière de la Baleine entrance with thicknesses reaching 30 m along the coast. It was deposited between 3500 BP and the present from remobilization of glacial sediments farther upstream due to river downcutting during emergence.

ABSTRACTThe Petite Rivière Pikauba valley was flooded following the failure of the Beloeil Dam, and its geomorphological description reveals a number of major modifications. The fluvial corridor, initially covered with thick till, now exhibits various erosion and disposition landforms which are surprisingly similar to those found in the fluvioglacial topographies of glacier ourbursts or catastrophic fluvioglacial surges resulting from the sudden, drainage of glacial lakes. The most obvious identification features associated with fluvioglacial glacier outburst topographies are dry glacioiacustrine basins, grooved morainic dams outburst deposits, deep grooves and terraces cut in till, fine sedimentation bars and islets, and bedrock erosion. Glacier outbursts are an extremely powerful phenomenon, likely to produce extensive geomorphological transformations. Consequently, they deserve serious consideration in the reconstruction of proglacial environments. The identifier elements were applied to a number of sites in Québec, revealing fluvioglacial glacier outburst topographies that had not been identified as such initially.

ABSTRACTCluster analysis of foraminifera from a ~12,000-9000 radiocarbon year old piston core from Goose Island Trough, Queen Charlotte Sound, indicates that a cold interval correlative with the Younger Dryas stadial occurred during a shallow water phase. The reduction in depth was caused by the passage across the area, between 11,500 and 10,000 years BP, of a glacial forebulge associated with the retreat of the Late Wisconsinian ice sheets. Published sedimentological evidence indicate that water depths decreased to ~75-90 m, placing the site above the permanent North Pacific pycnocline (100 m). Low salinity-near glacial conditions, at these depths, between -11,100 and 10,000 years BP were recognized by abundant populations of Cassidulina reniforme and lslandiella helenae. This cold interval has also been recognized in cores from elsewhere in Queen Charlotte Sound. The depressed salinity and temperature may have resulted from a modification of regional weather patterns. Decreased mean continental summer temperatures could have reduced the seasonal influence of the North Pacific High and lengthened that of the Aleutian Low. This would have resulted in a near continuous onshore surface Ekman transport and enhanced coastal runoff, effectively blocking the movement onto the shelf of deep, saline, warm water of the California Undercurrent. The resultant isolated inshore basin comprised of present-day Hecate Strait and Queen Charlotte Sound is tentatively named the "Hecate Sea". By ~10,000 years BP, weather and ocean circulation had returned to near modern patterns as indicated by the disappearance of lslandiella helenae and by the development of an Epistominella vitrea - dominated biofacies.

ABSTRACTThe manuscript documents voluminous new and published stratigraphie and paléontologie data from a region unique in North America, and possibly the world, in that it has abundant natural exposures recording a long and consistent succession of Quaternary tills and fossiliferous intertill sediments. Two major non-glacial intervals have been recognized under tills. Various non-glacial sediments have been correlated using their stratigraphie position, pollen analysis, and beetle assemblages, and are found to be equivalent to the Missinaibi Formation in Ontario. Non-finite high pressure radiocarbon dates, and aspartic acid ratios on wood suggest that the uppermost and most prevalent interval is of Sangamonian age. The Sangamonian record begins and ends with cool intervals, separated by a warmer period when climates were similar to or slightly warmer than present, and when the northern treeline was near its present position. The interval began with a high glacioisostatic sea, which regressed to levels below present Hudson Bay datum. The Sundance paleosol and silt beds below the Amery till relate to an earlier interglaciation characterized by cool tundra conditions. As an analogue for predicting future global change, the record preserved in the Hudson Bay Lowlands is second to none: additional intensive research is strongly recommended.