Caldera collapse in 1968 at the basaltic shield volcano, Fernandina, was preceded by lava effusion on the SE flank and a major explosive eruption on 11 June. The ash plume, seen here from Academy Bay on Santa Cruz Island within minutes of the explosion, is backlit by the late afternoon sun and was spreading at an estimated lateral speed of 80 km per hour. At the time of this photograph the ash plume was 175 km across with an altitude of 20-25 km.

Photo by J. Harte, 1968 (published in Simkin and Howard, 1970).

This image is made available under the Creative Commons BY-NC-ND 4.0 license terms.

Galleries: Ash Plumes and Ashfall

Keywords: explosive eruption | Plinian | ash plume | umbrella cloud | ash | eruption

Fernandina