BackgroundThe San Sebastián volcanic field, near the old silver-mining town of San Sebastián, is the northernmost of a belt of potassic volcanic fields located west of the main volcanic chain of western México. These geochemically unusual volcanoes owe their existence to their location at the conjunction of tectonic regimes involving the rifting of the Jalisco tectonic block and the subduction of the Rivera plate. The San Sebastián volcanic field consists of a group of scattered lamprophyric cinder cones erupted predominately through silicic ash-flow tuffs of the southern Sierra Madre Occidental province. The cinder cones and related lava flows, which erupted in a rugged and sparsely populated mountainous area that makes access difficult, range in age from 0.48 to 0.26 million years.
Source: Smithsonian / GVP volcano information
See also: Sentinel hub | Landsat 8 | NASA FIRMS