A closer look at water-related geologic activity on Mars.
نویسندگان
چکیده
Water has supposedly marked the surface of Mars and produced characteristic landforms. To understand the history of water on Mars, we take a close look at key locations with the High-Resolution Imaging Science Experiment on board the Mars Reconnaissance Orbiter, reaching fine spatial scales of 25 to 32 centimeters per pixel. Boulders ranging up to approximately 2 meters in diameter are ubiquitous in the middle to high latitudes, which include deposits previously interpreted as finegrained ocean sediments or dusty snow. Bright gully deposits identify six locations with very recent activity, but these lie on steep (20 degrees to 35 degrees) slopes where dry mass wasting could occur. Thus, we cannot confirm the reality of ancient oceans or water in active gullies but do see evidence of fluvial modification of geologically recent mid-latitude gullies and equatorial impact craters.
منابع مشابه
The formation and evolution of youthful gullies on Mars: Gullies as the late-stage phase of Mars’ most recent ice age
0019-1035/$ see front matter Published by Elsevier doi:10.1016/j.icarus.2009.06.018 * Corresponding author. E-mail address: [email protected] (J.L. Dickson) Gullies are extremely young erosional/depositional systems on Mars that have been carved by an agent that was likely to have been comprised in part by liquid water [Malin, M.C., Edgett, K.S., 2000. Evidence for recent groundwater seepage a...
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عنوان ژورنال:
- Science
دوره 317 5845 شماره
صفحات -
تاریخ انتشار 2007