Report on Kanlaon (Philippines) — 23 December-29 December 2015
Smithsonian / US Geological Survey Weekly Volcanic Activity Report,
23 December-29 December 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, 23 December-29 December 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 at 1457 on 23 December the seismic network at Kanlaon detected an explosion. The event was not visually observed due to dense weather clouds around the summit area but rumbling was heard in nearby barangays including Cabagnaan, La Castellana (16 km SW), and Ara-al and Yubo, La Carlota City (14 km W). Minor amounts of ash fell in Ara-al, Haguimit, and La Granja, La Carlota City, and a sulfur odor was noted in barangay Tres Elis, La Castellana. An explosive event detected by the seismic network at 2109 on 24 December was again not visually observed. Trace amounts of ash fell in Ara-al, Haguimit, and La Granja, and a sulfur odor was reported in Tres Elis. White steam plumes rose 100 m above the crater and drifted SW on 26 December. A five-minute long ash event that began at 1329 on 27 December was accompanied by rumbling heard in a few local barangays. An eruption plume, viewed from the SE flank, rose 1 km above the crater, and may have risen as high as 4.5 km based on pilot observations. Minor ashfall was noted in Ara-al, Yubo, and La Granja, Cabagnaan, Sag-ang (La Castellana), barangay Miranda, Hinigaran (Negros Occidental), Municipality of Pontevedra (Negros Occidental), and reached as far as Nueva Valencia, Guimaras (58 km WNW). The Alert Level remained at 1 (on a scale of 0-5).
Geological Summary. 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.