PHIVOLCS reported that two volcanic earthquakes at Kanlaon were accompanied by a one-minute, low-energy, gray ash emission at 0513 on 11 December. Observers noted ash emissions at 0951, 1008, 1140, and 0101 on 13 December which rose 200-300 m and drifted SW. The emissions were not detected by the seismic network, indicating a shallow source. Trace amounts of ashfall were reported in Sitio Bais, Brgy Yubo, and La Carlota City on the W flank and Brgy Sag-ang and La Castellana on the SW flank. The Alert Level remained at 1 (on a scale of 0-5).

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)