How wet are gullies on Mars? Insights from high resolution topography
نویسنده
چکیده
We have found that debris flows are the main process in forming two gullied crater slopes on Mars. We used 1 m/pix elevation models to derive three topographic indices: slope-area, CAD and DI-25. These indices allow the active slope processes to be identified by comparison to data from Earth analogues. We present data from Meteor Crater together with analogues previsouly presented by Conway et al. [1]. We also compare the signals from the martian gullied slopes with a non-gullied martian example: Zumba crater. Figure 1: Zones studied (in pink): A, Meteor Crater, image supplied by USGS. B, Zumba crater HiRISE image PSP_002118_1510. C, unnamed crater at 39°S, 160°E, HiRISE image PSP_006261_1410. D, unnamed crater at 38°S, 193°E, HiRISE image PSP_003939_1420.
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