In this VIS image, taken by the NASA - Mars Odyssey Orbiter on February, 26th, 2014, and during its 54.132nd orbit around the Red Planet, we can see a few (almost) triangularly-shaped Deposits located at the Edges of the Cliff (look at the very bottom of the frame) and technically known as Alluvial Fans.
The Alluvial Fans typically form in Arid (---> extremely Dry) Regions were the Water Flow was (almost always) extremely limited; in such a situation the Deposits of (various kinds of Rocky and Dusty) Materials were never washed away (since Floods never occurred in those areas). For instance, the formation of Alluvial Fans in the Martian Outflow Channel known as Kasei Vallis, most likely happened after any - even minimal - flow of fluid in the Valles System was definitively terminated.
Latitude (centered): 23,0851° North
Longitude (centered): 291,5250° East
This image (which is an Original Mars Odyssey Orbiter b/w and Map-Projected frame published on the NASA - Planetary Photojournal with the ID n. PIA 18223) has been additionally processed, magnified to aid the visibility of the details, contrast enhanced and sharpened, Gamma corrected and then colorized in Absolute Natural Colors (such as the colors that a human eye would actually perceive if someone were onboard the NASA - Mars Odyssey Orbiter and then looked down, towards the Surface of Mars), by using an original technique created - and, in time, dramatically improved - by the Lunar Explorer Italia Team.