Mounds of heaving


MOUNDS OF HEAVING (EN: frost mount hillbock, swelling hummock; DE: Aufblahungswellen, Quellenbeulen; FR: buttes de gonflement; ES: montones de hinchamiento; RU: бугры пучения) are the cryogenic (frosty) formations of the relief with the rounded shape, with the height from 20-40 centimetres to 30-40 metres, and with the diameter at the base from the few metres to 100-200 metres. These mounds form themselves during the freezing of the intensively watered or water-bearing dispersed rocks, as the result of the increasing of their volume. They distinguish the annual and perennial mounds of heaving. The first of these mounds emerge during the freezing of the seasonally-thawed and seasonally-frozen layers, and are destructed during their thawing; the second of these mounds develop themselves during the process of the multi-year deep freezing of the rocks. During the deep freezing of the clayish soils under the conditions with the unobstructed migration of moisture (the open water system), and with the accumulation of the lenses with segregated ice within the cores of the mounds, there form themselves the so-named migrational mounds of heaving. They are usually situated near the southern boundary of distribution of the permafrost rocks, and are associated with the places of the new formation of the frozen strata, and with the places of freezing.