The Philippine Institute of Volcanology and Seismology (PHIVOLCS) reported daily emissions and phreatic eruptions at Taal’s Main Crater during 31 July-6 August. There were five phreatic eruptions recorded, each lasting between 1 and 5 minutes. On 31 July diffuse emissions rose 500 m above the crater rim and drifted NE. During 1-6 August moderately dense to dense emissions rose as high as 2.4 km above the crater rim and drifted in several directions. The SO2 concentration was measured at 3,309 tonnes per day (t/d) on 2 August and 4,666 t/d on 5 August. 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 to take extra precaution around Main Crater and along the Daang Kastila fissure.

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)