Report on Taal (Philippines) — 24 March-30 March 2021
Smithsonian / US Geological Survey Weekly Volcanic Activity Report,
24 March-30 March 2021
Managing Editor: Sally Kuhn Sennert
Please cite this report as:
Global Volcanism Program, 2021. Report on Taal (Philippines). In: Sennert, S K (ed.), Weekly Volcanic Activity Report, 24 March-30 March 2021. Smithsonian Institution and US Geological Survey.
14.002°N, 120.993°E; summit elev. 311 m
All times are local (unless otherwise noted)
PHIVOLCS reported that seismicity increased at Taal during 24-27 March. There were around 19-302 volcanic earthquakes recorded daily, except on 28 March, and about 4-243 periods of volcanic tremor with variable durations (1-24 minutes). Four hybrid earthquakes were recorded on 24 March. Low-frequency earthquakes were detected 25, 77, 118, 7, and 16 times on 25, 26, 27, 28, and 30 March, respectively. Diffuse steam plumes from fumarolic vents in the Main Crater rose as high as 40 m. Daily measurements of sulfur dioxide emissions were 837-1,109 tonnes/day. The Alert Level for Taal remained at 2 (on a scale of 0-5). PHIVOLCS strongly recommended no entry onto the island, and access to the Main Crater and Daang Kastila fissure (along the walking trail) was strictly prohibited.
Geological Summary. Taal is one of the most active volcanoes in the Philippines and has produced some of its most powerful historical eruptions. Though not topographically prominent, its prehistorical eruptions have greatly changed the landscape of SW Luzon. 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, and several eruptive centers lie submerged beneath the lake. The 5-km-wide Volcano Island in north-central Lake Taal is the location of all historical eruptions. The island is composed of coalescing small stratovolcanoes, tuff rings, and scoria cones that have grown about 25% in area during historical time. Powerful pyroclastic flows and surges from historical eruptions have caused many fatalities.