What is the difference between rubble ice and pressure ridges?

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photo of rubble ice
photo of pressure ridge
photo of pressure ridges
Rubble ice
Pressure ridge
Pressure ridges

Pressure ridges are composed of ice fragments that are piled up along a line, with the steep-sloped ridge rising up as much as 5 to 10 feet or more above the adjacent stretches of level ice. 

Rubble ice, by comparison, is a jumble of ice fragments or small pieces of ice (such as pancake ice) that covers a larger expanse of area without any particular order to it. The height of surface features in rubble ice is often lower than in ridges. Rubble ice can cover large expanses, such as in Antarctica where the ocean swells breaks up newly forming ice and herds it together into rubble ice field.

Provided by Dr. Hajo Eicken

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