ice wedge
Quick Summary
Ice wedges are a prominent type of ground ice found in permafrost, characterized by their wedge-shaped formations that can be vertical or inclined sheets. These ice masses are typically 2.5 cm to 3 meters wide and 0.3 to 9 meters high when viewed in cross-section. They form part of polygonal networks that enclose areas of frozen ground, creating features known as polygonal ground or tundra polygons.12
Ice wedges are classified as active, inactive, or ice-wedge casts. Active ice wedges are currently growing, which requires very cold climates with mean annual air temperatures of -6 to -8 °C (21 to 18 °F) or colder. Inactive ice wedges are no longer growing, and ice-wedge casts are fossilized remnants found in areas that were once permafrost. These polygonal patterns are significant indicators of past or present permafrost conditions.12
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- ice formation
…most conspicuous of these is foliated ice, which frequently develops in thermal contraction cracks in permafrost as wedge-shaped, vertical, or inclined sheets 2.5 cm to 3 m (about 1 inch to 10 feet) wide and 0.3 to 9 m (1 to 30 feet) deep. Another prominent form is pingo ice,…
Read More…most conspicuous of these is foliated ice, which frequently develops in thermal contraction cracks in permafrost as wedge-shaped, vertical, or inclined sheets 2.5 cm to 3 m (about 1 inch to 10 feet) wide and 0.3 to 9 m (1 to 30 feet) deep. Another prominent form is pingo ice,…
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permafrostTypes of ground iceFoliated ground ice, or wedge ice, is the term for large masses of ice growing in thermal contraction cracks in permafrost.
Read MoreFoliated ground ice, or wedge ice, is the term for large masses of ice growing in thermal contraction cracks in permafrost.
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