ABSTRACT
Permafrost, or perennially frozen ground, influences virtually all aspects of man's activities in the regions which it underlies. In North America, the importance of permafrost was realised only recently, when attention focused on Alaska and other northern regions during and immediately after the Second World War. The Soviet Union, by virtue of its longer history of settlement in permafrost regions, was aware of these problems earlier than other countries and by the late 1920s had established a Permafrost Institute of the Siberian Academy of Sciences at Yakutsk in Eastern Siberia. Ground ice is a major component of permafrost, particularly in unconsolidated sediments. From the geotechnical and engineering viewpoint, the presence of ground ice is the problem most unique to permafrost regions and central to both thermokarst and frost-heave processes. The total amount of ground ice present varies from locality to locality.
