Geomorphology of Ius Chasma, Valles Marineris, Mars

Cartographic products of the Martian trough system, Valles Marineris, are useful to identify the diversity and complexity of geological activity that has occurred there. A huge fraction of the processes that have shaped the surface of Mars are also concentrated there. A geomorphological map of Ius Chasma in western Valles Marineris is presented. The map is published in three sheets at 1:260,000. It was drawn on the basis of 100 Mars Reconnaissance Orbiter’s Context Camera images of 12 m/pixel resolution, mosaiced using the USGS ISIS Planetary Image Processing Software, and subsequently mapped and interpreted for geomorphology in ArcGIS. The map displays 52 main geomorphological units of which some are further subdivided. They include both well-established features (e.g. spur-and-gully morphology on trough walls, landslide scars, and deposits), and newly reported landforms (e.g. alluvial fans with dendritic channels, moraines in western Ius Chasma). The proposed classifications of landslide deposits, glacial landforms, and floor areas are more detailed than on any previous map of Valles Marineris. The Ius Chasma map is the first cartographic product presenting a full inventory of dune fields, impact craters, light-toned outcrops, and mass-wasting features.