A small explosion February 8, 1999 at Colima volcano produced a plume of gas and minor ash that is seen here from the SE about 5 seconds after the explosion began. Rapid lava effusion beginning November 20, 1998 produced a lava dome in the 1994 crater that soon spilled over the crater rim, producing lava flows that descended the SW flank in several lobes. Block-and-ash flows from collapse of the flow fronts traveled down SW flank drainages. Periodic larger explosions occurred later during this eruption. Photo by Jim Luhr, 1997 (Smithsonian Institution).

Pico de Orizaba, North America's highest volcano, towers above limestone ridges on its ENE flank. The volcano is named for the city of Orizaba below its SE flank, but is also known by the Aztec name of Citlaltépetl (Star Mountain). The volcano has a rich cultural history. Its lower slopes host Aztec villages, pyramids, and temples. Its image adorns Aztec hieroglyphics and colonial and modern paintings, woodcuts, and lithographs. Photo by Lee Siebert, 1998 (Smithsonian Institution).

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At the end of the 9-year-long eruption of Parícutin, the new cinder cone rose 424 m above the surface of the original cornfield. The 900-m-wide oval-shaped cone is elongated in a NW-SE direction and is truncated by a circular, 280-m-wide crater. The western peak (right) is the highest point on the crater rim. The NE-flank peak of Nuevo Juatita in the foreground, its top covered by white fumarolic sublimate minerals, was the main source of lava flows during the last five years of the eruption. Photo by Jim Luhr, 1997 (Smithsonian Institution).

The snow-capped peak of México's Popocatépetl stratovolcano rises above Tlamacas to its north. Faint steam ascends from a deep elliptical summit crater, whose NE rim is 170 m below the summit. The sharp peak below the horizon at the right is Ventorrillo, the summit of the eroded Nexpayantla volcano, a predecessor to Popocatépetl. Its steep cliffs expose the stratified, layered interior of a stratovolcano. Photo by William Melson, 1968 (Smithsonian Institution).