Periglaciation
![Example of a periglacial landscape with both pingos and polygon wedge ice near Tuktoyaktuk, Northwest Territories](/Images/godic/202502/02/Melting_pingo_wedge_ice2830.jpg")
![A blockfield around 4000m on Mount Kenya](/Images/godic/202502/02/Frost_hexagons2830.jpg")
![A boulder field in Pennsylvania](/Images/godic/202502/02/HickoryRunBoulderField20072830.jpg")
Periglaciation (adjective: "periglacial," also referring to places at the edges of glacial areas) describes geomorphic processes that result from seasonal thawing of snow in areas of permafrost, the runoff from which refreezes in ice wedges and other structures. Tundra is a common ecological community in periglacial areas.