The Philippine Institute of Volcanology and Seismology (PHIVOLCS) reported that phreatic eruptive events at Taal periodically continued during 16-22 October. There were 1-2 phreatic events recorded almost daily during the week, with most lasting 2-14 minutes. Hot fluids upwelling in the lake were persistently observed, and daily steam-and-gas emissions that were sometimes voluminous rose as high as 1.8 km above the crater rim. Sulfur dioxide emissions averaged 1,577 tonnes per day (t/d) on 16 October and 1,256 t/d on 19 October. The Alert Level remained at 1 (on a scale of 0-5), and 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 and Taal Lake 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)