Global Volcanism Program | Image GVP-07614
The lava flows with levees in the center of the photo were extruded from a vent on the NE flank of Izalco beginning in 1955. This lava extrusion took place during an almost continuous period of Strombolian activity from November 1948 until the end of 1957. Periods of lava effusion took place July 1950, September-November 1952, October 1954, intermittently in 1955, November 1956, and January 1957. The eruption tapered off in late 1957 and was over by the end of the year.
Photo by Lee Siebert, 1999 (Smithsonian Institution).