The Philippine Institute of Volcanology and Seismology (PHIVOLCS) reported continuing eruptive activity at Kanlaon during 22-28 January. The seismic network recorded 8-35 daily volcanic earthquakes. Volcanic tremor was recorded during 25-27 January with 3-11 periods lasting 4-38 minutes at a time. Average daily sulfur dioxide emissions ranged from 1,691 to 4,222 tonnes per day. Continuous moderate to voluminous gas-and-steam emissions with occasional ash content rose 100-900 m above the summit and drifted SW and W. During 23-27 January there were 1-14 periods of ash emission lasting 2-65 minutes. The Alert Level remained at 3 (on a scale of 0-5); the public was warned to stay 6 km away from the summit and pilots were warned not to fly close to the volcano.

Geological Summary. Kanlaon volcano (also spelled Canlaon) forms the highest point on the Philippine island of Negros. The massive andesitic stratovolcano is covered 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 active vent, Lugud crater, to the south. Eruptions recorded since 1866 have typically consisted of phreatic explosions of small-to-moderate size that produce minor local ashfall.

Source: Philippine Institute of Volcanology and Seismology (PHIVOLCS)