Nuées Ardentes of the 1968 Eruption of Mayon Volcano, Philippines

James G. Moore; W.G. Melson

doi:10.1007/bf02596528

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Nuées Ardentes of the 1968 Eruption of Mayon Volcano, Philippines

James G. Moore·W.G. Melson

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Abstract

Mayon Volcano, southeastern Luzon, began a series of explosive eruptions at 0900 April 21, 1968, and by May 15 more than 100 explosions had occurred, at least 6 people had been killed, and roughly 100 square km had been covered by more than 5 cm of airfall ash, blocky ash flows, and a lava flow. All material crupted was porphyritic augite-hypersthene andesite. Explosions from the summit crater (elevation 2460 m) ejected large quantities of ash and incandescent blocks to a height exceeding 600 m and produced ash-laden clouds which rose to heights of 3 to 10 km. Backfall of the coarser material fed nuées ardentes which repeatedly swept down ravines on all sides of the volcanic cone. The velocity of one nuée ardente ranged from 9 to 63 m per sec. The largest nuées descended to the southwest and reached as far as 7 km from the summit. An aa lava flow also descended 3 1/2 km down this flank. The nuées ardentes deposited pyroclastic flows that contained large breadcrust-surfaced blocks averaging about 30 cm across, but occasionally reaching 25 m in greatest dimension. These blocks were still very hot in their interiors several days later. Surrounding the pyroclastic flows is a seared zone as much as 2 km wide, but averaging a few hundred meters, in which vegetation is charred and splintered, but over which only a thin layer of airfall ash was deposited.

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Bulletin Volcanologique Article

Source-reported bounding extent: 11.544616463449655° to 19.20742852680121° latitude; 119.3115234375° to 125.09033203124999° longitude. This indicates report coverage, not an exact sampling location. View area on OpenStreetMap.

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James G. Moore, W.G. Melson. 1969. Nuées Ardentes of the 1968 Eruption of Mayon Volcano, Philippines. https://doi.org/10.1007/bf02596528

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