Nivation

Nivation is a collective name for the different processes that occur under a snow patch. The primary processes are mass wasting and the freeze and thaw cycle,^[1] in which fallen snow gets compacted into firn or névé. The term glacier is applied only when ice has accumulated enough for the mass to achieve motion.^[2]

Nivation has come to include various subprocesses related to snow patches which may be immobile or semi-permanent. These sub-processes include erosion (if any) or initiation of erosion, weathering, and meltwater flow from beneath the snow patch.^[2]

Weathered particles are moved downslope by creep, solifluction and rill wash.^[1] Over time, this leads to the formation of nivation hollows which, when enlarged, can be the beginnings of a cirque.^[1]

References

1. ^ ^{a b c} Easterbrook, Don J. (1999). Surface Processes and Landforms (2nd ed.). New Jersey: Prentice Hall. p. 334. ISBN 0-13-860958-6. 
2. ^ ^{a b} Potter, Franklin C. (September, 1949), "Nivation", Crater Lake Nature Notes XV (1), http://www.nps.gov/archive/crla/notes/vol15b.htm#3