Flow rates and duration within Kasei Valles, Mars: Implications for the formation of a martian ocean

Calculated maximum discharges for the largest outflow channel system on Mar s, Kasei Valles, based on elevation data fi om the Mars Orbiter Laser Altim eter (MOLA), 2 to 4 orders of magnitude lower (8 x 10(4) - 2 x 10(7) m(3) s (-1)) are than estimated previously. Mars Orbiter Camera (MOC) images show morphological evidence consistent with these relatively modest flow rates. Topographic profiles of the outflow channels reveal previously unrecognized narrow, inner channels. Development of a sapping channel network between f low events suggests the system was active over a significant period of time and likely involved several separate flood events. The longer formation hi story and lower discharge rates may require a long fill time (>25 years) an d a warmer climate to form a martian ocean.