Global Volcanism Program | Image GVP-04045
The active crater of Santa Ana volcano lies at the SE end of series of four nested summit craters and contains a small lake not visible in this photo. The northern crater wall in the background exposes a series of lava flows and inter-bedded fragmental deposits. Several faults, such as the one at the upper left, are visible in the crater walls. The eastern side of Santa Ana's crater was breached and then refilled. Later tectonic movements produced a graben in the central part of the crater with displacements of 50-70 m.
Photo by Bill Rose, 1966 (Michigan Technological University).