Geology Reference
In-Depth Information
Barn
Mountains
Beaufort
Plain
Continental
Glaciation
ICE
400 kms
Late Pleistocene
Unglaciated in Late Pleistocene
Middle Pleistocene
Unglaciated in Middle Pleistocene
Early Pleistocene/Late Pliocene
Never-glaciated
Figure 2.2. Maximum Limits of Quaternary glaciation in the western Canadian Arctic (after
Vincent, 1982, 1989; Duk-Rodkin et al., 2004). Also indicated are the main paleo - drainage systems
and locations of Beaufort Plain and Barn Mountains. See Figure 11.4 for approximate ages and
correlations between Cordilleran and Continental glaciations.
from the fl anks of the moraine, probably associated with melt-out of buried glacier-ice
bodies. At some point, the northward drainage of the Beaufort Plain became impounded
against the McClure Strait ice lobe and formed a series of proglacial water bodies that
subsequently overfl owed westward. A shallow, box-shaped, and progressively widening
spillway channel was eroded. This is also visible on Figure 2.3. Clearly, the extreme north-
western part of Banks Island experienced a classic Lozinski-type, ice-marginal location
during the Late Pleistocene.
Third, although climatic data are unavailable for this remote and uninhabited area, one
can assume that conditions are similar to those at Sachs Harbour (Ikaahuk) (72° N) and
Resolute Bay (74° N) (Table 2.1A). The climate is cold, with mean annual air temperatures
approximately
50 °C. The region has
less than 200 mm of rain or snowfall-equivalent a year. The frost-free period is limited to
between 10 and 30 days per year. Permafrost typically exceeds 250 m in thickness and the
maximum active-layer thickness probably never exceeds 60-75 cm (French, 1970).
12 to
15 °C. Winter extremes may be as low as
 
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