Global Volcanism Program | Image GVP-07992
The three coalescing Cerro San Pedro lava domes (center), seen here from the NE, were constructed within the 7 x 10 km wide San Pedro caldera. The ridge at the left is the eastern rim of the caldera, which cuts andesitic-to-dacitic lava domes of early Pleistocene age. The dacitic San Pedro lava domes were dated at 0.75-0.80 million years and were constructed along a WNW-trending line. Two of the domes have partially collapsed, forming large debris-avalanche deposits that reach up to 10 km from the source.
Photo by Jim Luhr, 1978 (Smithsonian Institution).
This image is made available under the Public Domain Dedication CC0 license, but proper attribution is appreciated.