Multiple new fissures (cracks) were observed around Taal volcano on January 14, 2020, two days after intense unrest began. Fissures, accompanied by intense seismicity activity, are an indication of an imminent explosive eruption, PHIVOLCS warns. The agency strongly reiterated total evacuation of Taal Volcano Island and areas at high risk to pyroclastic density currents and volcanic tsunami within a 14 km (8.6 miles) radius from the volcano. Areas around the volcano are advised to guard against the effects of heavy and prolonged ashfall. New eruption could force more than 200 000 additional people from their homes.
Taal volcano entered a period of intense unrest beginning with phreatic / steam-driven eruption at several points inside the Main Crater at 06:04 UTC on January 12, 2020. The activity progressed into a magmatic eruption from 08:49 to 20:28 UTC, characterized by weak lava fountaining accompanied by thunder and flashes of lightning. According to the Tokyo VAAC, volcanic ash cloud reached an altitude of 16.7 km (55 000 feet) above sea level. Sulfur dioxide (SO2) emission was measured at an average of 5 299 tonnes/day on January 13, 2020.
In 24 hours to 00:00 UTC on January 14, the activity was characterized by the continuous eruption at the Main Crater due to magmatic and hydrovolcanic activity. This ongoing eruption generated 500-meter (1 640 feet) tall lava fountains topped by dark gray steam-laden plumes reaching approximately 2 km (1.2 miles) that dispersed ash to the southwest and west of the Main Crater. Flashes of volcanic lightning were observed at the base of the degassing plumes.
New vents opened up on the northern flank, with 500 m (1 640 feet) tall lava fountains, and within the main crater where steam plumes, have emanated.
Heavy ashfall from the ongoing continuous activity has fallen on the municipalities of Lemery, Talisay, Taal, and Cuenca, Batangas.
By 02:00 UTC on January 14, PHIVOLCS registered a total of 336 volcanic earthquakes, of which 133 were felt -- M1.2 to 4.1.
At 05:00 UTC, lava fountains generated 800 m (2 620 feet) tall dark gray steam-laden plumes that drifted to the general southwest.
New fissures or cracks were observed in Sinisian, Mahabang Dahilig, Dayapan, Palanas, Sangalang, Poblacion, Lemery; Pansipit, Agoncillo; Poblacion 1, Poblacion 2, Poblacion 3, Poblacion 5, Talisay and Poblacion, San Nicolas. A fissure was also documented across the road connecting Agoncillo to Laurel, Batangas.
PHIVOLCS said that fissuring on the caldera region means that the top of the volcano has been depressurized and the high volume of magma continues to rise, indicating an imminent explosive eruption. Another indication of an impending explosive eruption is an intense seismic activity.
The agency added that similar fissures have appeared before the explosive eruption of 1911 (January 27 - February 8; VEI 3).
Nuevas fisuras y grietas descubiertas en áreas alrededor del volcán #Taal son un indicio de una inminente erupción explosiva, dijo el martes por la tarde el Instituto Filipino de Vulcanología y Sismología (@phivolcs_dost). pic.twitter.com/LzaSOw0ktx
— Alejandro S. Méndez (@asalmendez) January 14, 2020
Ashfall from the #Taal eruption. Source: News5 pic.twitter.com/UznMiiOUXb
— René Goad (@RenVolcanoman) January 14, 2020
A total of 40 752 people were affected; of which 38 203 are taking temporary shelter in 198 evacuation centers, NDRRMC reported at 10:00 UTC today.
The eruption grounded 603 flights (362 domestic and 241 international) due to volcanic ash. Of which, 177 have resumed operations by 18:00 LT, January 14.
Power interruptions were experienced in 7 cities/municipalities on January 12. School classes were suspended in 260 cities/municipalities in Regions II, CALABARZON and NCR. As of January 14, classes in 118 cities/municipalities have resumed.
Agricultural damage is estimated at 1.45 million USD in the provinces of Batangas and Cavite.
Alert Level 4 still remains in effect - this means that hazardous explosive eruption is possible within hours to days.
PHIVOLCS strongly reiterates total evacuation of Taal Volcano Island and areas at high risk to pyroclastic density currents and volcanic tsunami within a 14 km (8.6 miles) radius from Taal Main Crater. Areas around Taal Volcano are advised to guard against the effects of heavy and prolonged ashfall.
#Update: Here are some of the mind blowing pictures of the ash spewing volcano on the island of #Taal in the #Philippines. pic.twitter.com/Y39LNc3S3A
— Sotiri Dimpinoudis (@sotiridi) January 12, 2020
#Update: The #Taal volcano has already caused lots of damages on the island and to peoples health, up to 4-5 inches of Volcanic ash is covering the area. #Philippines Phil pic.twitter.com/89qANhiwHE
— Sotiri Dimpinoudis (@sotiridi) January 13, 2020
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 topography of SW Luzon. The 15 x 20 km (9 x 12 feet) Talisay (Taal) caldera is largely filled by Lake Taal, whose 267 km2 (103 mi2) surface lies only 3 m (9.8 feet) above sea level.
The maximum depth of the lake is 160 m (525 feet), and several eruptive centers lie submerged beneath the lake. The 5-km-wide (3.1 miles) 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 the area during historical time. Powerful pyroclastic flows and surges from historical eruptions have caused many fatalities. (GVP)
Featured image credit: Paul Quiambao