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Banks Island is a polar desert where continental ice sheets, spreading from a dispersal centre to the southeast, reached their maximum extent on at least three occasions. The oldest Banks Glaciation affected all but the northwest. The Pre-Banks Sea preceded glacierization while the Post-Banks Sea formed during déglaciation. Following Morgan Bluffs Interglaciation, characterized by a climate similar to that of today, the south, the east, and the Thomsen River basin were covered during Thomsen Glaciation. The Pre-Thomsen Sea preceded the glacierization, while the Big Sea inundated much of the Island during déglaciation. Following the last or Cape Collinson Interglaciation, characterized by a climate warmer than that of the hypsithermal, Laurentide glacial lobes impinged on the coastal areas, during the M'Clure Stade of Amundsen Glaciation. Prince of Wales and Thesiger lobes, emanating from Amundsen Gulf, respectively advanced in Prince of Wales Strait and Thesiger Bay impinging on the east and southwest coasts. At the same time, Prince Alfred Lobe, originating in Viscount Melville Sound, advanced in M'Clure Strait and impinged on the north coast. The Pre-Amundsen Sea preceded the glacierization of the south coast, while the East Coast Sea submerged the east coast up to 120 m, the Meek Point Sea the west up to 20 m and the Investigator Sea the north up to 30 m, during déglaciation. The late Sand Hills Readvance of Thesiger Lobe built a morainic system on the southwest coast. Later, the northeast was covered, during the Russell Stade of Amundsen Glaciation, by Viscount Melville Lobe, emanating from Viscount Melville Sound, and the east coast was drowned up to 25 m by the Schuyter Point Sea. Limits of extent of Laurentide ice in the southwestern Archipelago are proposed for the two stades of the last or Wisconsinan Glaciation.

On présente une nouvelle interprétation de révolution des phases lacustres des lacs glaciaires Barlow et Ojibway, à partir d’une synthèse des données recueillies sur le versant québécois des bassins de l’Outaouais supérieur et de la baie de James. Ces nappes d’eau (11 500 et 7900 ans BP) ont été les dernières d’une série continue de lacs qui suivirent la marge glaciaire laurentidienne depuis le début de la dernière déglaciation. Les lignes de rivage associées à ces phases lacustres montrent que l’altitude maximale des plans d’eau se relève vers le nord-nord-est et que le relèvement différentiel varie entre 0,5 et 1,2 m/km. Le niveau des eaux était contrôlé par des séries d’exutoires localisés aux ruptures de pente le long de l’axe fluvial constitué par les vallées de l’Outaouais, de la rivière des Quinze et du Kinojévis. Le tracé des plans de déformation des niveaux lacustres comparé au profil longitudinal actuel de ces vallées montre qu’au moment de la déglaciation, la ligne de partage des eaux a été déplacée loin vers le sud. Ce gauchissement temporaire de la surface a permis la rétention des eaux du lac Barlow. La coupure entre les lacs Barlow et Ojibway représente la rupture de pente la plus importante de tout l’axe fluvial. Son emersion a confiné les eaux du lac Barlow au bassin du Témiscamingue et a donné naissance à un autre lac indépendant, le lac Ojibway, qui s’est agrandi vers le nord et le nord-est sur le territoire nouvellement déglacié.A new interpretation of the lacustrine phases of these glacial lakes is presented, based on a synthesis of the data collected from the upper Ottawa River and James Bay drainage basins in Québec. These water bodies (11,500 and 7,900 BP) were the penultimate lake phases in a series of proglacial lakes that followed the retreating Laurentide ice margin from its late Wisconsinan maximum stand. Shorelines associated with these lacustrine phases show that the maximum elevation of the water planes are tilted up towards the north-northeast and that differential uplift varies from 0.5 to 1.2 m/km. Lake levels were controlled by series of outlets situated at slope inflections along the Ottawa, Des Quinze, and Kinojevis river system. The plot of the water-level planes on the long profile of the present river valleys indicates that at the time of déglaciation, the drainage divide was displaced far to the south by isostatic delevelling. It was this temporary deformation of the earth's surface that retained Lake Barlow waters. The separation of lakes Barlow and Ojibway represents the most important inflection of slope in the whole fluvial system. The emergence of this sill confined Lake Barlow waters to the Témiscaming basin and created Lake Ojibway, a completely independent lake that extended towards the north and northeast on the recently deglaciated terrain