The Philippine Institute of Volcanology and Seismology (PHIVOLCS) reported eruptive activity at Taal during 23-30 December. The seismic network recorded 0-8 daily volcanic earthquakes along with 4-6 daily periods of volcanic tremor lasting 2-23 minutes during 26-27 December. Daily gas-and-steam emissions generally rose as high as 20 m above the crater rim and drifted SW and NE. One minor phreatomagmatic event occurred at 1636 on 26 December, lasted two minutes, and consisted of four pulses of activity. Short dark jets of material were ejected above the surface of Main Crater Lake and fell back down into the water. Light-gray to whitish plumes rose 600 m above the crater rim and drifted SW. The Alert Level remained at 1 (on a scale of 0-5); PHIVOLCS reminded the public that the entire Taal Volcano Island (TVI) was a Permanent Danger Zone (PDZ) and recommended that the Main Crater and areas along the Daang Kastila fissure should remain prohibited. Pilots were warned to avoid flying over TVI.

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)