Pingos

Pingos are very large domes made of earth and soil, while their core is made of solid, clear ice. As water seeps into spaces in the ground it freezes and creates "lenses" of ice which gradually grow in size as more and more water seeps in. As they grow larger and gain mass, the ground above them is pushed upwards into huge domes. Pingos can be 50-metres high and 900-metres wide. In some, the ice lens has melted and the dome has collapsed into a volcano-shaped hill.

What is the structure of a pingo?

 

 

 

 
Location of pingos in the Canadian Arctic.