Pediment Surface on Mars?
Layers at the base of Mount Sharp (photo taken by Curiosity Rover); http://www.nasa.gov/mission_pages/msl/multimedia/pia16105.html
And now for some armchair speculation of Martian geomorphology based on two minutes of looking at a photo. Why not, right? The photo above was taken by the Curiosity rover and nicely shows the stratigraphy at the base of Mount Sharp. Very nice.
Upon closer examination it appears some layers are truncated by an erosional surface that parallels the sloping mountain front. The photos below are zoomed in and cropped to highlight one such area. The lower photo includes some simple annotation showing that truncation relationship (yellow line).
I didn’t have time to find a good Earth analog, but I’ve definitely seen erosional features like this, termed pediments, out in the deserts of Utah. Perhaps this is old news for those who study Mars, I don’t know. I just thought it was interesting. Besides, Mars!!
Those who know much more about Mars and/or desert landforms, please feel free to add info in the comments below.
Clastic Detritus 
Hi Brian – I don’t have anything intelligent to add, but funny you should post this, since I had exactly the same reaction: a first look at this extraordinary image and then “Wow – that’s an erosional surface up there, some kind of unconformity above all those truncated beds….” As you say, why not?
Shame our friend Curiosity won’t be able to just clamber up for a quick look!
“… armchair speculation of Martian geomorphology based on two minutes of looking at a photo …”. Well, at least you have actual credentials that qualify you to hold an opinion, unlike some folks commenting on “analysis” of Mars photos.
Pretty cool post, thanks.