An oblique, color image of central Valles Marineris, Mars showing relief of Ophir and Candor Chasmata; view toward north. The photograph is a composite of Viking high-resolution images in black and white and low-resolution images in color. Ophir Chasma on the north is approximately 300 km across and as deep as 10 km. The connected chasma or valleys of Valles Marineris may have formed from a combination of erosional collapse and structural activity. Tongues of interior layered deposits on the floor of the chasmata can be observed as well as young landslide material along the base of Ophir Chasma's north wall.