Report on Taal (Philippines) — 10 November-16 November 2021
Smithsonian / US Geological Survey Weekly Volcanic Activity Report,
10 November-16 November 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, 10 November-16 November 2021. Smithsonian Institution and US Geological Survey.
14.002°N, 120.993°E; summit elev. 311 m
All times are local (unless otherwise noted)
Three short (1-3 minutes) phreatomagmatic bursts at Taal were recorded at 2339 on 15 November, and at both 0146 and 0254 on 17 November. The first generated a plume that rose 2.4 km and drifted SW and the next two events generated plumes that rose 400-500 m based on thermal camera images. PHIVOLCS stated that the events were likely driven by fracturing and gas release from magma beneath the Taal Volcano Island.
Sulfur dioxide emissions averaged 9,448-12,516 tonnes/day during 10-16 November. Upwelling hot volcanic fluids were visible in the crater lake, and daily gas-and-steam plumes rose 0.7-1.5 km above the lake and drifted mainly SW. Low-level background tremor continued to be recorded. During 9-12 November the seismic network recorded 135-223 volcanic earthquakes per day, and as many as 72 low-frequency volcanic earthquakes per day, and 70-180 daily episodes of volcanic tremor, each lasting 1-3 minutes. Three hybrid earthquakes were recorded during 9-10 November. No earthquakes were detected during 12-13 November. Seismicity then increased during 14-16 November with a few periods of tremor (1-3 minutes long), 9-10 daily volcanic earthquakes, and 3-4 daily low-frequency volcanic earthquakes. The Volcano Alert Level remained at a 2 (on a scale of 0-5). PHIVOLCS reminded the public that the entire Taal Volcano Island is a Permanent Danger Zone (PDZ) and that boating on Taal Lake was 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.