The Philippine Institute of Volcanology and Seismology (PHIVOLCS) reported continuing eruptive activity at Kanlaon during 4-11 March. The seismic network recorded 3-19 daily volcanic earthquakes, including 1-2 periods of volcanic tremor lasting from five minutes to three hours and two minutes during 6-7 and 9 March. Average daily sulfur dioxide emissions ranged from 1,712 to 3,144 tonnes per day. Gas-and-steam emissions that were often continuous and occasionally contained ash rose as high as 300 m above the summit and drifted NW, W, and SW. There were 1-2 periods of ash emissions lasting 1-15 minutes during 4-5, 7, and 9 March, and seven periods of ash emissions on 6 March lasting eight minutes to nearly three hours. 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)