The origin of underground ice is discussed, including the burial of glaciers, the creation of ice through cryosuction, ice injection, and through the growth of ice wedges that may lead to the formation of
yedoma, a Russian term for ice complex.
The ice complex or yedoma is loess-like syngenetic frozen soils of the Pleistocene age with high thickness, forming the northern coastal lowlands, the plains of Central Yakutia, and the northeast.
Stephani, "Cryostratigraphy of late Pleistocene syngenetic permafrost (yedoma) in northern Alaska, Itkillik river exposure," Quaternary Research, vol.
"Spatial Analyses of Thermokarst Lakes and Basins in
Yedoma Landscapes of the Lena Delta." The Cryosphere 5 (4): 849-867.
The transformation of illite and chlorite to randomly interstratified illite-smectite and chlorite-smectite respectively in circum-neutral to weakly acidic conditions has been documented for permafrost-affected soils Kriozems (Cryosols) formed in the cold, continental, climate of the Kolyma Lowland, North-East Siberia, as has the extremely weak intensity of chemical weathering of the Yedoma deposits (Alekseev et al., 2003).
Illite normally loses interlayer potassium and converts to a mixed layer dioctahedral illite-vermiculite in the upper acidic horizons of such soils or even to illitesmectite as it was shown for soils of Yedoma deposits (Alekseev et al., 2003) and it seems that this is a likely explanation for the loss of illite in the upper horizons of the Cryosols.