[1] It is cited as an efficient mode of permafrost growth, compared with heterogenetic permafrost growth, which occurs when freezing temperatures penetrate into previously unfrozen ground of uniform composition.
Lunardini gives the basic formulas for permafrost generation under both modes.
[1] Studies of such formations are partly based on observations in the Cold Regions Research and Engineering Laboratory tunnel into permafrost near Fairbanks, Alaska.
[3] Ice wedges that intrude into cracks in permafrost may be regarded as syngenetic, if they grow upwards.
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