Report on Kanlaon (Philippines) — 18 November-24 November 2015
Smithsonian / US Geological Survey Weekly Volcanic Activity Report, 18 November-24 November 2015
Managing Editor: Sally Kuhn Sennert
Please cite this report as:
Global Volcanism Program, 2015. Report on Kanlaon (Philippines). In: Sennert, S K (ed.), Weekly Volcanic Activity Report, 18 November-24 November 2015. 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 the seismic network for Kanlaon detected an explosion-type signal beginning at 0930 on 23 November, culminating with an 8-minute-long steam explosion. Observers reported that a white plume rose 1-1.5 km above the crater and drifted SW, and rumbling was heard in local areas. Only four volcanic earthquakes had been recorded during the previous week, but after the explosion, the network detected volcanic tremor that lasted for five hours. The Alert Level was raised to 1 (on a scale of 0-5). Continuous steam emissions with minor ash content were observed the next morning.
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.