A fascinating phenomenon of mountain permafrost are the so-called “rock glaciers”. These debris bodies with often striking “porridge-like” or “lava stream-like” deformational appearance are formed by viscous creep of ice-rich permafrost.

From core drillings and geophysical soundings, ice contents of such creeping permafrost are known to exceed the contents of rock particles by commonly about a factor of two or so. This “ice supersaturation”, “excess ice” or “ice with rock inclusions” enables unlimited long-term creep deformation. Modern technologies like exposure dating of surface blocks document that still active rock glaciers have been underway for many thousand years since the termination of the last Ice Age.

Global warming causes permafrost temperatures to increase. This makes the creeping rock-ice mixtures “warmer”, more easily deformable. In strongest contrast to glaciers, rock glaciers therefore tended to accelerate their movement and to continue advancing. Information about their distribution and evolution is systematically collected as part of global permafrost and climate monitoring.