The Birds of West-Central Ellesmere Island and Adjacent Areas

Bird-Banding ◽  
1961 ◽  
Vol 32 (2) ◽  
pp. 110
Author(s):  
M. M. Nice ◽  
David F. Parmelee ◽  
S. D. MacDonald
1990 ◽  
Vol 27 (2) ◽  
pp. 255-270 ◽  
Author(s):  
John England

Moraines and meltwater channels mark the limit of the last glaciation that interfingered with the sea around the perimeter of Greely Fiord and its tributaries. The extent of this ice advance was dictated predominantly by its proximity to the sea. Consequently, the large tidewater glaciers at the fiord heads today were so constrained by calving that they advanced only 5–10 km. Similarly, grounding-line deposits from widespread plateau ice caps also terminate just below marine limit. The most extensive outlet glaciers, which advanced 20–35 km beyond present margins, are simply those that had access to the most extensive terrain above marine limit, i.e., the northwest margin of the Agassiz Ice Cap.Forty-one new 14C dates are presented. The onset of the last ice advance must predate marine shells collected from sediments overlying a former grounding line when sea level was 122 m higher than present. At this site, the lowermost shells collected from glaciomarine silts dated 38 070 ± 410 BP, whereas a surface sample 13 m above them dated 22 900 ± 190 BP. Although both dates may be minimum estimates, they are nonetheless associated with an ice margin that retreated only a few kilometres by 7850 BP, suggesting the maintenance of the glacioisostatic loading (and relative sea level) during the interim. Nearby, shells in growth position overlying bedrock confirm that relative sea level was > 83 m asl by 38 010 ± 410 BP (minimum age). These marine deposits lie outside the last ice limit and are not overlain by glacigenic sediments.Distal to the last ice limit, Greely Fiord was occupied by the full glacial sea, whose limit is marked by discontinuous beaches and wave-cut benches. The full glacial sea rises from 116 m north of Greely Fiord to a maximum elevation of 148 m bordering its south shore from which it descends to 112 m asl near the head of Cañon Fiord. Numerous 14C dates on shells collected within 8 m of marine limit show that the full glacial sea remained stable from at least 8400 to 7400 BP. Several other shell samples collected ~20 m below marine limit are much older (> 22 000 BP). The position of relative sea level between ca. 8000 and > 22 000 BP is uncertain; however, stratigraphic evidence for an intervening regression has not been found.The modest extent of the last ice limit encircling Greely Fiord, together with its occupancy by the full glacial sea, is fully compatible with the paleogeography previously reported from northeast Ellesmere Island and northwest Greenland. Furthermore, this data base provides a reinterpretation of a 500 km transect previously reported along west-central Ellesmere Island to the south and affirms that the Innuitian Ice Sheet, defined sensu stricto for the last glaciation, is supplanted by the full glacial Innuitian Sea, which penetrated the Queen Elizabeth Islands, constraining the last ice limit.


1985 ◽  
Vol 22 (3) ◽  
pp. 347-368 ◽  
Author(s):  
D. A. Hodgson

Locally abundant ice-marginal landforms lie in a 500 km long zone with a distal margin 10–60 km west of the margins of modern 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 modern 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 western 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.


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