North–south topographic slope asymmetry on Mars: Evidence for insolation-related erosion at high obliquity
نویسندگان
چکیده
[1] A map of north–south subkilometer-scale slope asymmetry on Mars obtained from statistical analysis of along-track MOLA topographic profiles reveals welldefined zonal belts of north–south slope asymmetry at 40–50 latitude in both hemispheres. In these narrow anomalous belts the pole-facing slopes are systematically gentler than equator-facing slopes. This asymmetry is especially pronounced for the steepest (>20 ) slopes, in which pole-facing slopes are three times less frequent than >20 slopes facing the equator. We interpret these belts to be related to insolation asymmetry. Specifically, we suggest that summertime melting of ground ice on pole-facing slopes occurred during periods of very high obliquity ( 45 ) in the past and favored downslope movement of material and reduction of steep pole-facing slopes.
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