Geoscience Reference
In-Depth Information
Fig. 4.6
Examples of non-sorted patterned ground: ice-wedge polygon in the Canadian Arctic
(
upper left
; photo by Agriculture and Agric-Food Canada; a frost boil in the Alaskan Arctic
Foothills; photo by J. Bockheim); earth or turf hummocks in Greenland (
lower left
; photo by
Philipp Gaugler;
http://www.tuhlig.de
); strangmoor in the Alaskan Arctic Foothills (
lower cen-
ter
; photo by D.A. Walker); and a palsa near Tromso, Norway (
lower right
; photo by scien-
cenordic.com)
Fig. 4.7
Formation of ice-wedge polygons (Pidwirny
2006
)
4.3.1.3
Earth Hummocks
Earth hummocks were studied in detail by Tarnocai and Zoltai (
1978
) in the
Canadian arctic and subarctic. The hummocks have an average diameter of
80-160 cm and an average height of 40-60 cm. They develop on mineral materials
and have abundant ice. The development of earth hummocks is controlled by soil
