Some 35% of Earth's land area undergoes regular freezing and thawing. Ice heaving and ice wedging are two of the mechanisms by which water in soil lifts, penetrates, and sorts soils and rocks when repeatedly melted and frozen. Ice heaving is the lifting of soil by horizontal ice layers; ice wedging is the top-down growth into soil of vertical wedges of ice.

Ice heaving is driven by complex molecular interactions between water and soil. The simple result of these complex interactions is that ice forming in soil sucks water to itself by capillary action. The suction exerted by ice upon water in soil is termed cryosuction. Since freezing normally proceeds from the surface down, ice heaving begins with the formation of a layer of ice near the surface. As it grows, this layer draws water to itself from below by cryosuction. This water...