In this nice VIS image, taken by the NASA - Mars Odyssey Orbiter on February, 16th, 2015 and during its 58.444th orbit around the Red Planet, numerous (extremely well defined - and therefore relatively "fresh") Gullies are visible on the Cliff-Face of a Surface Depression located within the Floor of the large Lyell Crater.
Lyell Crater is an Impact Crater found in the Mare Australe Quadrangle of Mars, and centered at 70,1°South Latitude and 15,6° West Longitude. It is approx. 131 Km (such as about 81,351 miles) in diameter, and it was so named after Charles Lyell (who was born on November, 14, 1797 in Kinnordy, Angus - Scotland - and died on February, 22, 1875, in London - England).
Just out of curiosity, the name of this Crater was approved in the AD 1973 by the International Astronomical Union (or "IAU", for short) Working Group for Planetary System Nomenclature.
Latitude (centered): 69,3387° South
Longitude (centered): 346,0150° East
This frame (which is an Original Mars Odyssey Orbiter b/w and Map-Projected frame published on the NASA - Planetary Photojournal with the ID n. PIA 19280) has been additionally processed, magnified, contrast enhanced 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.