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Arches National Park Geology Tour provides an extensive, visually rich description of the geology of Arches, by Deborah Ragland, Ph.D. See our DVD collection.
This is a diagram of the nine different kinds of ice.
Click on image for full size
Image from: Bridgeman, [1937]

There are Nine Different Kinds of Ice

The phase of ice means the form of ice which takes shape. There are nine different kinds of shapes the ice crystal can assume. It all depends upon what temperature the ice feels, and what pressure the ice is under. The diagram tells under what environment to expect to find these different kinds of ice.

A basic ice cube from your refrigerator is known as Ice I, which is the form of ice which exists at the temperatures and pressures in the bottom left corner of this diagram. If the temperature get high enough, that form of ice melts, just as an ice cube would on your kitchen table, and forms water.

As a moon evolves, it may cool down from a period of being warm. The question is whether it is presently warm enough inside a moon for ice to be in motion, to form layers of water, or for evidence of interior activity to be produced visibly on the surface.

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Windows to the Universe, a project of the National Earth Science Teachers Association, is sponsored in part by the National Science Foundation and NASA, our Founding Partners (the American Geophysical Union and American Geosciences Institute) as well as through Institutional, Contributing, and Affiliate Partners, individual memberships and generous donors. Thank you for your support! NASA AGU AGI NSF