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Locally abundant ice-marginal landforms lie in a 500 km long zone with a distal margin 10-60 km west of the margins of modem ice caps on central Ellesmere Island. Much of this drift belt, at the heads of the fiords, was deposited by the oscillating margin of a coalesced predecessor of the modem ice caps between 9000 and 7000 BP. The ice continued to retreat east of the present margin, and readvanced to its modern limit in a middle and late Holocene cooler climate. Unweathered but undated till and striations at the base of the drift suggest that the belt does not mark the western limit of central Ellesmere Island ice in the last glaciation. The limit lies an unknown distance downfiord; glaciers in the fiords may have floated. No reliable evidence was found for a complete ice cover of westem Ellesmere Island and Eureka Sound in the last glaciation; nevertheless much of central and southern Ellesmere Island and Devon Island may have been glaciated by a regime that left few erosional or depositional landforms. Alternatively, emergence of an unglaciated Eureka Sound, underway by 9000 BP, may have followed combined peripheral glacioisostatic depression by encircling ice caps, whereas at the drift belt emergence was less and later, controlled only by central Ellesmere Island ice.Des formes de terrain localement abondantes en bordure de glaciers apparaissent dans un zone longue de 500 km avec une marge CloignCe de 10-60 km i I'ouest des marges des calottes glaciaires au centre de I'ile Ellesmere. Une part importante des apports glaciaires de cette zone, i la tCte des fjords, a td dkpode par la marge oscillante d'un prkdkcesseur composite des calottes glaciaires actuelles, il y a entre 9000 et 7000 annCes avant le prksent. Le glacier continuait B reculer ?i I'est de la marge actuelle, et reavan~ait jusqu'i la limite contemporaine sous le climat plus froid de 1'Holockne moyen et sup6rieur. Un till nonalted mais d'age indetermink et des striations ti la base du drift rkvklent que la zone n'etait pas la limite occidentale de la calotte de glace du centre de I'ile Ellesmere durant la dernikre englaciation. La limite se situe ?i une distance inconnue en aval des fjords; les glaciers dans les fjords ont pu flotter. Aucun indice fiable ne tkmoigne de la presence d'une couverture compkte de glace sur I'ile Ellesmere et le dCtroit Eureka durant la demikre englaciation, nkanmoins une partie importante du centre et du sud de I'ile Ellesmere et de I'ile Devon a pu Ctre envahie par les glaciers dotes d'un regime produisant peu de formes de dBp6ts ou de terrains sculptes par 1'Brosion. Alternativement, 1'Cmergence d'un detroit Eurkka exempt d'englaciation, il y a 9000 amkes avant le present, est possiblement survenue aprks la formation de la depression glacioisostatique p6riphkrique combink par I'encerclement des calottes glaciaires, tandis que dans la zone de drift 1'Cmergence etait moins et plus tardivement, contr6lCe par la glace du centre de I'ile Ellesmere.

Moderately to completely weathered Devonian clastic rocks caver much of central Melville Island, including Dundas Peninsula. The principal Quaternary deposits are till and ice contact gravels, which occur in central and southeastern Dundas Peninsula. Deltaic and marine nearshore and beach sediments are scattered along lowland coasts. Continental ice sheets, dispersing from the south, reached their maximum limits on central Melville Island during at least three episodes; only the age of the last advance has been determined. The oldest and most extensive glaciation recognized covered at least southern Dundas Peninsula up to 300 m a.s.l. and deposited Dundas Till plus a major belt of ice contact deposits. During a subsequent glaciation, ice from Parry Channel overlapped the south-central coast of Dundas Peninsula up to 100 m a.s.l. and deposited Bolduc Till. This deposition may have occurred at the same time that ice entered Liddon Gulf from the south, depositing Liddon Till to 100 m a.s.l. on the outer gulf coast. At 11 700 ± 100 BP, all coasts were rising after crustal depression by ice assumed to have occupied Parry Channel and possibly covered the central Queen Elizabeth Islands. Maximum emergence on the south coast is at least 90 m; on all coasts farther north a prominent (and highest) water plane is recorded at about 55 m a.s.l. Subsequent to this initial emergence, ice from Parry Channel readvanced over, and retreated from, the south coast of Dundas Peninsula probably between 10 340 ± 150 and 9670 ± 150 BP, depositing Winter Harbour Till up to 120 m a.s.l. Because shoreline emergence was not significantly interrupted by this readvance, it is concluded that off shore this ice sheet was probably floating. Local ice caps existed at undetermined times on the uplands of Melville Island, north of Dundas Peninsula.