igikeltsa alal mineraalpinnases leiduva vee külmumisest ja pinnase kerkimisest tingitud ajutine positiivne jääst tuumaga pinnavorm, periglacial temporary positive landform. Hummock with ice dome on the land surface that occurs due to buried ice lenses upwards growth in mineral soil of permafrost areas. Can reach up to 70 metres in height and up to 600 m in diameter being larger than similar landforms in peat deposit called palsas.