62: Tofua volcano erupts, sending ash cloud 3,000 feet above Tonga Islands

 

by The Extinction Protocol

August 14, 2012 – TONGA - A “new” volcano just entered the watch list: Out in the Pacific, a pilot observed an ash cloud rising from Tofua volcano to 3,000 ft (ca. 1 km) in the Tonga Islands at 04:42 GMT, VAAC Wellington reports. The volcano last erupted in 2009. –Volcano Discovery.  Historical background: Tofua Caldera, in Tonga, is the summit caldera of a steep-sided composite cone that forms Tofua Island. Tofua Island is in Tonga's Ha'apai island group. Pre-caldera activity is recorded by a sequence of pyroclastic deposits and lavas constituting the older cone, followed on the northern part of the island by froth lavas or welded and unwelded ignimbrite. Following caldera collapse, lavas were erupted from the northern part of the island and the caldera-rim fissure zone, scoria and lavas from the caldera-wall fissure zones, pyroclastics and lavas from intracaldera cones, and recent pyroclastic fall deposits on the outer cone. Eruptive products are mainly basaltic andesites and andesites, plus occasional dacite flows within the older cone. A post-caldera cone with fumarolic activity (Lofia) is situated in the northern part of the caldera; a crater lake with 500 m (1,600 ft) depth occupies most of the remainder. Most historical eruptions have been small explosions from Lofia cone along the northern caldera rim. The eruptions of 1958-59 caused most of the islanders to evacuate for a year or more. –Wikipedia