Timescales of fluvial activity and intermittency in Milna Crater, Mars

Combining the timescales of fluvial activity in the adjacent Paraná Valles with estimates for global Noachian erosion rates, we calculate an intermittency factor for fluvial activity of ∼0.01-0.1% during 105-106 yr near the Noachian-Hesperian boundary in the Paraná Valles region. These values are comparable to arid climates on Earth where the majority of fluvial sedimentary transport takes place during floods with multi-year to decadal recurrence intervals. Our calculations of intermittency help to quantitatively reconcile the divergent estimates of the short and long timescales of fluvial activity on Mars reported in the literature.