PHIVOLCS reported continuing low-level unrest at Taal during 6-13 June characterized by elevated seismicity, upwelling in the lake, and sulfur dioxide gas emissions. Volcanic tremor located at shallow depths along the Daang Kastila fissure was continuous with almost 166 hours recorded during 2-9 June; periods of volcanic tremor also took place 4-7 times each day during 9-12 June, each lasting 2-97 minutes. There were 1-11 volcanic earthquakes recorded on most days. Upwelling gasses and hot fluids in the lake continued to be visible almost daily, and voluminous white steam-and-gas plumes that rose as high as 3 km above the lake drifted NW, E, and SSE. Daily sulfur dioxide emissions averaged 2,941-6,884 tonnes per day. The steam-and-gas plumes produced voggy conditions in the caldera during 6-9 June, prompting an advisory to the public to be issued on 7 June. 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)