In this VIS image, taken by the NASA - Mars Odyssey Orbiter on September, 22nd, 2004, and during its 12.307th orbit around the Red Planet, we can see a really small part of the extremely ancient Martian Region known as Arabia Terra. The (relatively) dark gray tone in this Absolute Natural Color image (see the lower portion of the frame) is often associated, as you should already know, with the presence, on the Surface, of large amounts of Basaltic (such as Volcanic, in origin) Sand.
Latitude (centered): 3,44332° North
Longitude (centered): 5,97644° East
This image (which is an Original Mars Odyssey Orbiter falsely colored and Map Projected frame published on the NASA - Planetary Photojournal with the ID n. PIA 19794) has been additionally processed, magnified to aid the visibility of the details, extra-contrast enhanced and sharpened, Gamma corrected and then re-colorized in Absolute Natural Colors (such as the colors that a normal 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.