Features of Ophir Chasma (CTX Frame - Absolute Natural Colors; credits for the additional process. and color.: Dr Paolo C. Fienga/Lunar Explorer Italia/Italian Planetary Foundation)

The really huge Landslides existing along the Walls of Ophir Chasma (which is nothing else but a deep Canyon located in the Coprates Quadrangle of Mars, at about 4° South Latitude and 72,5° West Longitude. It is approx. 317 km long and it was so named after a "Classical Albedo Feature") host a variety of Geologic Surfaces and Mineralogies.
Some of them possess a variety of Hydrated Sulfate Minerals that formed, eons ago, in the presence of Partially Acidic Liquid Water. This NASA - Mars Reconnaissance Orbiter's Contextual (or "CTX", for short) Image, which is representing an ancient (possibly and approximately 3 Billion Years-old) Landslide, shows us the presence, within it, of 2 (two) very distinct Surface Albedoes, which, in fact, mark a Transition Zone from one Sulfate Mineralogy to another (a circumstance that proves beyod doubts the occurrence, in a far and distant past, of some remarkable variations in the evolution of the visible Surface).
The Upper Slopes (such as the ones located towards the North) are light-toned, and this fact is due to the concurrent abundance of Hydrated Sulfate Minerals and Bright Surface Dust. On the other hand, the Surfaces that make up the Southern Portion of the Landslide, are darker in tone, and this is due to the greater abundance of Dark Sediment that, in time, formed "Strings of Sand Drifts". In addition to the above, the underlying Units of Bedrock consist of Darker Minerals that received a lesser hydration then the Northern ones, and this further circumstance implies the occurrence of a strong (and, perhaps, sudden) change in the Ancient Aqueous Environments that formed them.

Mars Local Time: 14:52 (Early Afternoon)
Coord. (centered): 4,328° South Lat. and 288,657° East Long.
Spacecraft altitude: 271,0 Km (such as about 168,291 miles)
Original image scale range: 27,1 cm/pixel (with 1 x 1 binning) so objects ~ 81 cm across are resolved
Map projected scale: 25 cm/pixel
Map projection: EQUIRECTANGULAR
Emission Angle: 6,3°
Phase Angle: 52,7°
Solar Incidence Angle: 47° (meaning that the Sun was about 43° above the Local Horizon at the time the picture was taken)
Solar Longitude: 27,0° (Northern Spring - Southern Fall)
Credits: NASA/JPL/University of Arizona
Additional process. and coloring: Lunar Explorer Italia

This picture (which is a NASA - Original Mars Reconnaissance Orbiter b/w and NON-Map Projected frame identified by the serial n. PSP_007535_1755) has been additionally processed, magnified, contrast enhanced, 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 Reconnaissance 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.