Fractured Lavas Suggest Floods on Mars
This image shows an exposure of layered rock that exhibits a type of fracturing -- called columnar jointing -- that results when cooling lava contracts. Image credit: NASA/JPL-Caltech/University of Arizona
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February 25, 2009
Images from NASA's Mars Reconnaissance Orbiter show a type of rock fracturing that here on Earth is caused by rapid cooling of lava.
For the full story, go to the release from the U.S. Geological Survey at http://www.usgs.gov/newsroom/article.asp?ID=2146 .