Earth News This Week

Thursday, February 21, 2008

Deltas on Mars

Martian water flow

The Nature paper from Utrecht University is a fascinating mix of observationsand modelling!

Erin R. Kraal, Maurits van Dijk, George Postma & Maarten G. Kleinhans

Nature 451, 973-976(21 February 2008)




The colour-coded digital terrain model (a; colour bar shows mm below measuring surface) and fan profile (b) clearly show the transition from the crater floor (CF) into an alluvial fan (AF) with a prominent delta lobe (DL) transitioning to the feeding stream canyon (SC). High infiltration rates caused a slow rise in water level followed by an abrupt increase following local saturation (c). Initially, sediment was transported in concentrated flows (d) then, as stream power decreased, the fan transitioned to sheet flow deposition (e).