Report on Taal (Philippines) — 14 July-20 July 2021
Smithsonian Institution / US Geological Survey
Weekly Volcanic Activity Report, 14 July-20 July 2021
Managing Editor: Sally Sennert.
Please cite this report as:
Global Volcanism Program, 2021. Report on Taal (Philippines) (Sennert, S, ed.). Weekly Volcanic Activity Report, 14 July-20 July 2021. Smithsonian Institution and US Geological Survey.
14.0106°N, 120.9975°E; summit elev. 311 m
All times are local (unless otherwise noted)
PHIVOLCS reported that unrest at Taal continued during 13-20 July. Daily plumes of steam and sulfur dioxide gas rose 0.9-2.1 km from the lake and drifted in multiple directions. Sulfur dioxide emissions averaged 1,142-6,574 tonnes/day. Two tremor events, at 1018 and 1038 on 20 July, were felt at Intensity I by residents of Pira-piraso in the NE sector of Volcano Island. The DROMIC report stated that 3,839 people were in evacuation centers or private residences by 20 July. The Alert Level remained at 3 (on a scale of 0-5) and PHIVOLCS reminded the public that the entire Taal Volcano Island is a Permanent Danger Zone (PDZ) and to not enter the high-risk barangays of Agoncillo and Laurel. Activities on Taal Lake were strictly prohibited.
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.