Global Volcanism Program | Image GVP-00971
A powerful eruption of Pinatubo volcano that began at 0555 on 15 June 1991 viewed from Clark Air Base ENE of the volcano. The broad ash column, which appears to be as wide as the volcano, is a result of pyroclastic surges that are sweeping radially down the volcano's flanks. Surge-producing eruptions began the afternoon of 14 June and continued intermittently until the climactic eruption about 24 hours later. It began at 1342 on the 15th and resulted in caldera collapse during sustained eruptions that lasted more than 6 hours.
Photo by Robert LaPointe, 1991 (U.S. Air Force).