Krugger M.I., Stern H.P. (Eds.) New Permafrost and Glacier Research

New York: Nova Science Publishers, Inc., 2009. — 326 p. — ISBN: 1606926160.In geology, permafrost or permafrost soil is soil at or below the freezing point of water (0 °C or 32 °F) for two or more years. Ice is not always present, as may be in the case of nonporous bedrock, but it frequently occurs and it may be in amounts exceeding the potential hydraulic saturation of the ground material.