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JET PROPULSION LABORATORY
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PHOTO CAPTION                      Model for Water Flow on Mars
                                   June 22, 2000                         

This is a model to explain a process that might have led to the 
formation of newly discovered features on Mars that suggest there 
may be current sources of liquid water at or near the surface.  
The model shows how it would be possible for water to flow down 
the gullies instead of just boiling off the surface.  When water 
evaporates it cools the ground, which would cause the water 
behind the initial seepage site to freeze. This would result in 
pressure building up behind an 'ice dam'.  Ultimately, the dam 
would break and send a flood down the gully.

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