Izalco grew to its present height during a 200-year period since it began erupting in 1770 at an elevation of about 1,300 m on the flank of Santa Ana. Intermittent Strombolian eruptions and the effusion of dominantly basaltic-andesite lava flows built up the volcano so that by the year 1866 the summit was at 1,825 m elevation, by 1866 it was at 1,825 m, by 1892 it was at 1,885 m, by 1951 it was at 1,900 m, by 1953 it was at 1,935, and by 1956 it was at 1,965 m.

Photo by Lee Siebert, 2002 (Smithsonian Institution).

This image is made available under the Public Domain Dedication CC0 license, but proper attribution is appreciated.

Keywords: stratovolcano

Izalco