Report on Kanlaon (Philippines) — 19 July-25 July 2006
Smithsonian / US Geological Survey Weekly Volcanic Activity Report, 19 July-25 July 2006
Managing Editor: Sally Kuhn Sennert
Please cite this report as:
Global Volcanism Program, 2006. Report on Kanlaon (Philippines). In: Sennert, S K (ed.), Weekly Volcanic Activity Report, 19 July-25 July 2006. Smithsonian Institution and US Geological Survey.
10.412°N, 123.132°E; summit elev. 2435 m
All times are local (unless otherwise noted)
Based on interpretations of seismic data, an explosion at Canlaon that lasted more than 10 minutes occurred on 23 July. An ash column was not observed due to cloud cover. Trace deposits of ash fell up to 9 km ENE of the crater in the neighborhoods of Pula, Malaiba, and Lumapao. On 24 July, PHIVOLCS reported a total of 16 volcanic earthquakes, 3 short-duration tremors, and 2 earthquakes indicating small explosions. Ash was not observed.
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 2435-m-high 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 to the SW from Kanlaon. The summit of Kanlaon 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 from Kanlaon, recorded since 1866, have typically consisted of phreatic explosions of small-to-moderate size that produce minor ashfalls near the volcano.