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EMERGENT
ARCTIC COASTAL LANDSCAPE AND SEDIMENTS OF NORTHWESTERN FOXE
BASIN, CANADA
I.P.
MARTINI and S. SADURA
Department
of Land Resource Science, University of Guelph, Guelph, Ontario, Canada
Foxe Basin is a downfaulted arctic basin floored by
Paleozoic carbonates and surrounded by crystalline Precambrian terrains. Its
exposed Quaternary deposits consist of a thin veneer of glacial drift and frost
shattered bedrock, locally reworked during isostatic emergence (approximately 75
cm/century for the last 4000 years). Three major types of coasts develop: (1)
jagged, steep rocky coasts with pebbly pocket beaches and some bouldery ice push
ridges in coves, (2) coasts with well developed beach ridges, (3) very low
energy muddy coasts in a few large embayments. Development of narrow Puccinelia
phryganodes salt marsh is limited to muddy and few local sandy shores.
Although strong storm waves are generated during the ice free times, the long 10
months per year persistence of the ice cover on the shallow, mesotidal sea
ensures that the overall energy of these coasts is low, and little reworking of
the sediments occurs. As the land emerges, several characteristic permafrost
features develop. These include frost heaving of bedrock blocks, frost boils in
flatter areas and solifluction lobes in steeper slopes, frost shattering and
solution of surficial carbonate pebbles, and formation of shallow soils which
reach a maximum depth of 1 m in sandy areas, down to the permafrost table. |
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