Report on Kanlaon (Philippines) — 30 March-5 April 2016
Smithsonian / US Geological Survey Weekly Volcanic Activity Report, 30 March-5 April 2016
Managing Editor: Sally Kuhn Sennert
Please cite this report as:
Global Volcanism Program, 2016. Report on Kanlaon (Philippines). In: Sennert, S K (ed.), Weekly Volcanic Activity Report, 30 March-5 April 2016. Smithsonian Institution and US Geological Survey.
10.412°N, 123.132°E; summit elev. 2435 m
All times are local (unless otherwise noted)
PHIVOLCS reported that long-duration tremor began at Kanlaon at 0130 on 30 March. The tremor was accompanied by gas-and-steam plumes that rose 600-700 m and drifted SW and SSW during 30 March-1 April. On 31 March minor ashfall was reported in areas downwind including in parts of La Carlota City (14 km W), La Castellana, and Bago City in Negros Occidental. The tremor continued during 2-4 April, though the energy decreased, and steam plumes rose 400-500 m. On 5 April steam plumes rose 800 m and drifted SW. The Alert Level remained at 1 (on a scale of 0-5).
Geologic Background. Kanlaon volcano (also spelled Canlaon), the most active of the central Philippines, forms the highest point on the island of Negros. The massive andesitic stratovolcano is dotted with fissure-controlled pyroclastic cones and craters, many of which are filled by lakes. The largest debris avalanche known in the Philippines traveled 33 km SW from Kanlaon. The summit contains a 2-km-wide, elongated northern caldera with a crater lake and a smaller, but higher, historically active vent, Lugud crater, to the south. Historical eruptions, recorded since 1866, have typically consisted of phreatic explosions of small-to-moderate size that produce minor ashfalls near the volcano.