Global Volcanism Program | Image GVP-09974
The escarpment cutting diagonally downward across the middle of the photo, its face highlighted by vertical rows of trees in coffee plantations, is the NW wall of a large caldera formed by edifice collapse of Santa Ana volcano during the late Pleistocene. About 5 km of the avalanche caldera rim is exposed; the remainder is buried beneath ejecta and lava flows from modern Santa Ana volcano. Conical Cerro los Naranjos volcano rises beyond the scarp, and other peaks of the Apaneca range form the horizon on either side.
Photo by Lee Siebert, 2002 (Smithsonian Institution).