groundwater circulation

This had a pronounced effect on the development of deep groundwater circulation and of Krubera Cave in particular.

This suggests the existence of a deep karst system and vigorous karst groundwater circulation at depth.

The water may come from precipitation, groundwater circulation (often hydrothermal fluids in the case of volcanic craters) or melted ice.

It has been proposed that the aquifers could be recharged on geological time scales by a sequence of sublimation of the frozen seeps, atmospheric circulation of the vapor to the southern polar ice cap, redeposition of this onto the cap, basal melting under the ice mass, and groundwater circulation on a global scale.