occurring at low temperatures, where liquid
erupts through an overlying crust of ice.
Cryovolcanism can be thought of as a similar process to normal volcanism: the difference being that the magma in cryovolcanism is a watery-liquid. This liquid is circulated and erupted by the internal heat of the planetary body (usually a moon).
The liquid probably consists of brine containing magnesium and sodium sulphates; at extremely low temperatures ammonia may also be present.
Cryovolcanism is known to be active on Enceladus, Europa, and Ganymede.