Digital Terrain Models / High resolution 3D Model of Mars NASA/JPL-Caltech/UArizona - High Resolution Imaging Science Experimenthttps://www.uahirise.org/PSP_008391_1790This image shows part of the floor of Orson Welles Crater, an old impact crater now connected with the Shalbatana Valles outflow channel. Part of the floor of the crater is comprised of large hummocks comparable to those found in other “chaotic terrain” on Mars; such areas are often the sources of giant flood channels.Examined closely, the light-toned areas consist of finely-layered materials, partially buried by dark mantling material and sand dunes. Such light-toned rocks are found at a number of sites on Mars and are thought to be sedimentary. Notable color variations occur in the rocks may be a result of different compositions.