Volcanic quakes to persist due to Taal Volcano unrest, Phivolcs says

enablePagination: false
maxItemsPerPage: 10
maxPaginationLinks: 10

Metro Manila (CNN Philippines, January 13) — Earthquakes triggered by the ongoing steam-driven eruption of Taal Volcano will continue, state seismologists said on Monday.

Philippine Institute of Volcanology and Seismology (PHIVOLCS) Director Undersecretary Renato Solidum warned that earthquakes of less than Magnitude 4 and strong shaking will persist in areas near the Taal Volcano in Batangas.

"It means there is continued movement of significant volume of magma. That can still persist as long as magma is still moving up the volcano," he told CNN Philippines.

A resident of Taal, Batangas said residents in the area were panicking and crying on Sunday night following the numerous tremors.

A total of 75 volcanic earthquakes have been recorded in the Taal region as of early Monday morning. 32 of these were felt with up to Intensity 5 or strong shaking.

Solidum warned that constant volcanic quakes can also loosen the wall of the Taal crater.

"One concern with the continuous stronger shaking, slopes might be loosened along the crater wall of the bigger caldera. So people have to be cautious if their houses are in the steep slopes," the official said.

Volcanic tsunami possible

PHIVOLCS said a volcanic tsunami is possible when Taal Volcano enters the fifth and highest threat level. Solidum said volcanic tsunamis are triggered by falling debris after a volcanic eruption. The debris can push the water and generate waves towards the shoreline.

"These kinds of hazards have happened during major eruption events, such as in the 60s and 1911 eruptions. It's not that high compared to typical earthquake tsunami in open seas but this can damage and impact people if they are on the shore," he said.

Solidum reminded residents near and around the active volcano to follow the evacuation order for those within the 14-kilometer radius of the volcano’s crater.

No hazardous movement yet

Alert Level 4 over Taal Volcano on Sunday afternoon, warning it have a “hazardous explosive eruption" within hours or days. 

Early Monday morning, the Taal crater spewed a lava fountain, which is the expected activity of the volcano, Solidum said. He said this does not mean there is an increased activity that should cause panic. He said this only means that lava has reached the surface of the volcano.

"We haven't seen yet the hazards of the 1965, 1911, and 1754 eruption manifested in Taal Volcano. [If it is a hazardous eruption], we will see flows of ashes, rocks, gas at speeds of more than 60 kph horizontally and that can move across the lake," he said.

Phivolcs said the steam-driven eruption progressed into a magmatic eruption at 02:49 AM to 04:28 AM on Monday. This is characterized by the "weak" lava fountaining. 

Taal showed a marked increase in volcanic activity on Sunday with an ash plume at around 2pm. PHIVOLCS raised alert levels two, three and four in a period of a few hours. The seismological agency, however, has been monitoring the volcano since March 2019.

Taal is one of the shortest volcanoes in the world and is the second-most active volcano in the Philippines. Its last eruption was in 1977.