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Frost polygons and mudboil-covered area
Location: Kaminak Lake Area, Kivalliq, Nunavut, Canada
Frost polygons and mudboil-covered area

Date taken: summer 1973
Photo ID: 0068
High resolution image available
Useage statement
 

This image, scanned from a rather dirty 35 mm slide, shows contrasting patterned ground features on a low, flat, terrain of poorly-drained, grass-sedge meadow and a relatively well-drained, slightly raised area formed on till and marine silty-clay. The former terrain, though probably underlain by marine silty clay, also, is ornamented by frost polygons because of the shallow (45-75 cm) depth of annual thaw in the peat, which keeps the underlying mineral sediments permanently frozen and rigid. The till/marine sediment terrain is ornamented, as is typical in this region, by mudboils and solifluction stripes (see image 0240 for a more complete explanation). This photo was taken from an altitude of 300-500 m. Frost wedges, such as those illustrated in images 0064, 0067, 0211 and 0212, probably extend downward from the frost cracks.

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Updated 04/25/2007 CAB