New research by a team from Brown University has developed strong evidence regarding subsurface water flow on Mars in the past. They studied thousands of ridges found in crater-rich regions and came to the conclusion that the ridges were the result of mineral deposits from flowing water. These deposits worked their way into the surrounding rock and were harder thereby causing the ridges to form.
Mineral deposits mark subsurface water flowA photo taken by the Mars Reconnaissance Orbiter shows ridges formed by fossilized subsurface water flow. Orientation of the ridges, mapped by researchers, is consistent with fractures formed by impact events. Credit: NASA and Mustard Lab/Brown University
Read More ABout It: http://news.brown.edu/pressreleases/2013/01/marswater
Sky Guy in VA