Martian gullies in the southern mid-latitudes of Mars: Evidence for climate-controlled formation of young fluvial features based upon local and global topography
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چکیده
A new survey of Mars Orbiter Camera (MOC) narrow-angle images of gullies in the 30◦–45◦ S latitude band includes their distribution, morphology, local topographic setting, orientation, elevation, and slopes. These new data show that gully formation is favored over a specific range of conditions: elevation (−5000 to +3000 m), slope (>10◦), and orientation (83.8% on pole-facing slopes). These data, and the frequent occurrence of gullies on isolated topographic highs, lead us to support the conclusion that climatic-related processes of volatile accumulation and melting driven by orbital variations are the most likely candidate for processes responsible for the geologically recent formation of martian gullies. © 2006 Elsevier Inc. All rights reserved.
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Evidence for recent groundwater seepage and surface runoff on Mars.
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