Report on Kanlaon (Philippines) — 19 January-25 January 2005
Smithsonian / US Geological Survey Weekly Volcanic Activity Report, 19 January-25 January 2005
Managing Editor: Gari Mayberry
Please cite this report as:
Global Volcanism Program, 2005. Report on Kanlaon (Philippines). In: Mayberry, G (ed.), Weekly Volcanic Activity Report, 19 January-25 January 2005. Smithsonian Institution and US Geological Survey.
10.412°N, 123.132°E; summit elev. 2435 m
All times are local (unless otherwise noted)
A brief ash emission began at Canlaon around 0930 on 21 January. The cloud produced from the emission rose to an approximate height of 500 m above the active crater and drifted WNW and SW. No coincident volcanic earthquakes were recorded. There were fine ash deposits in the city of Cabagnaan, ~5.5 km SW of the crater. PHIVOLCS advised the public to avoid entering the 4-km-radius Permanent Danger Zone around the volcano.
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.