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Definition:
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A massive, generally wedge-shaped body with its apex pointing downward, composed of foliated or vertically banded, commonly white Ice. The size of Ice Wedges varies from less than 10 cm to more than 3 m in width at the top, commonly tapering to a feather edge at a depth of 1 to more than 10 m. Ice Wedges are formed in thermal contraction cracks (Figura 33) in which hoar frost forms and into which water from melting Snow penetrates in the spring. Repeated annual contraction cracking of the Ice in the wedge, followed by freezing of water in the crack, gradually increases the width (and possibly the depth) of the wedge and causes vertical banding of the Ice mass. The surface expression of Ice Wedges is generally a network of Polygons. Ice Wedges growing as a result of repeated winter cracking are called Active Ice Wedges. Inactive Ice Wedges can be stable and remain for many centuries without changing. Ice Wedges are more common in arctic environments than mountains due to differences in soil properties, topography and availability of water.
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