PHIVOLCS reported that sulfur dioxide emissions at Taal averaged 3,802-6,844 tonnes per day during 9-10 and 12-15 August; a high of 13,572 tonnes per day was recorded on 11 August causing significant vog around the caldera and a sulfur odor reported by residents of Banyaga, (Agoncillo), Poblacion 5, Boso-boso, and Gulod (Laurel), and Poblacion (Talisay). Upwelling volcanic gasses and fluids in the lake were visible, along with voluminous steam-rich plumes that rose as high as 3 km above the lake and drifted mainly NE, SE, and SW. 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).

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)