An increase in Strombolian eruptions at Arenal had begun in March 1990. An ash plume rises above the summit on 4 April 1990, seen here from the volcano observatory 2.5 km S. This was part of a long-lived eruption that began in 1968. Explosions produced ash plumes to heights of 1 km above the summit and were accompanied by a lava flow that descended the Río Tabacón on the NW flank down to 700 m altitude. Small pyroclastic flows were also produced.

Photo by William Melson, 1990 (Smithsonian Institution)

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

Keywords: eruption | ash | ash plume | explosive eruption

Arenal