Past History of a Wet Mars Seen at Libya Montes
Scientists report on identification of clays and carbonate that formed on early Mars in a liquid water environment near a large impact basin. Coordinated analyses using multiple datasets were used to characterize the composition and stratigraphy of the region. A paper published online in April 2013 in the Journal of Geophysical Research highlights new mineralogic and geologic observations at a site called Libya Montes just south of the Isidis Basin on Mars. “Liquid water is likely to have been present on the surface or subsurface of this region when the clays and carbonates formed” says Janice Bishop, SETI Institute scientist and lead author on the paper.
This 3D image provides a view ~40 km wide of the mountains and a valley in the Libya Montes region using a composite mosaic of MRO-CTX and MEx-HRSC overlain on a Digital Terrain Model (DTM) from HRSC and vertically enhanced by 2.5X. Co-author Daniela Tirsch of the DLR in Berlin who prepared these maps describes that “the clay units are exposed below the olivine-bearing unit at several sites where the wind abrasion has scoured the surface”. The colored sites are compositional maps from MRO-CRISM where the pyroxene-bearing basalt is mapped in blue, olivine-rich basalt is mapped in green and Fe/Mg-clays are mapped in red.