Re: M1901170
MOLA topography of the dune field in Russel crater is sparse but some profiles are available here:
http://marsoweb.nas.nasa.gov/MOLA/regions/15_39/
The main dune is about 500 metres above the crater floor, and lesser ones ramp down in waves from it, to the west.
The flow features in M1901170 originate on the crest of the main dune.
(Oh and BTW, their Java and the one for this posting page REALLY don't like each other!)