As a training for segmenting Martian topography, I have done a little work on Earth.
Using the software LandSerf by Prof. Jo Wood (the website www.landserf.org appears to be down at the moment), I created a number of derived topograhic layers from Shuttle Radar Topography mission data, i.e. slope, aspect, and plan, longitudinal, cross-sectional, profile and mean curvature. I then layerstacked these files (taking the aspect in degrees from north-facing).
Using RSGISlib to segment these (using min 128px sized objects where a pixel is ~ 72m) I get results like this:
The curvature layers seem to enable it to segment along ridge and valley lines and it can sometimes be seen how the topography is orientated spatially.