The Philippine Institute of Volcanology and Seismology (PHIVOLCS) reported continuing eruptive activity at Taal during 11-18 February. There were 0-12 daily volcanic earthquakes and a few periods of tremor that lasted from one minute to as long as two hours and nine minutes. Three minor phreatic eruptions occurred on 12, 15, and 16 February, each lasting 3-4 minutes. Daily gas-and-steam emissions generally rose 350-900 m above the crater rim and drifted NW, W, and SW, though on 16 February plumes rose as high as 2.1 km. Sulfur dioxide emissions averaged 448, 407, and 1,244 tonnes per day on 12, 15, and 17 February, respectively. The Alert Level remained at 1 (on a scale of 0-5); PHIVOLCS reminded the public that the entire Taal Volcano Island was a Permanent Danger Zone (PDZ) and recommended that the Main Crater and areas along the Daang Kastila fissure should remain prohibited.

Geological Summary. Taal is one of the most active volcanoes in the Philippines and has produced some powerful eruptions. The 15 x 20 km Talisay (Taal) caldera is largely filled by Lake Taal, whose 267 km2 surface lies only 3 m above sea level. The maximum depth of the lake is 160 m, with several submerged eruptive centers. The 5-km-wide Volcano Island in north-central Lake Taal is the location of all observed eruptions. The island is composed of coalescing small stratovolcanoes, tuff rings, and scoria cones. Powerful pyroclastic flows and surges have caused many fatalities.

Source: Philippine Institute of Volcanology and Seismology (PHIVOLCS)