Finely-Layered Rocks in Ius Chasma (extra-detail mgnf - MULTISPECTRUM; credits: Lunexit)

Much of this Region has been covered by dust and sand, which appears brownish-red. This material is eroded by wind over time and allows us to see the light-toned rock underneath the surface.
There are also dunes that obscure portions of the outcrop.

Many outcrops within Ius Chasma and elsewhere on Mars are covered by such dunes and dust, but the high spatial resolution of instruments such as HiRISE and CRISM allow us to see the Geology and Mineralogy of regions between these dunes to help unravel the Geologic History of Mars.