A destructive and deadly eruption could still be in the works even though Taal Volcano appeared calm on Wednesday, the Philippine Institute of Volcanology and Seismology said.
“The explosive eruption scenario and this is the scenario we have been preparing for together with the Batangas Provincial Risk Reduction and Management Office, is still possible simply because… we still have a lot of earthquakes and ground deformation within the area,” PHIVOLCS director Renato Solidum said in an interview on ANC Headstart.
The agency also said the volcano’s continued activity has drained its main crater lake of water, as seen in new satellite images and drone video footage.p
Mariton Bornas, chief of PHIVOLCS’ Monitoring and Eruption Prediction Division, said the dried lake was related to the movement of magma up the volcano but said it was not a sign for an explosive volcanic eruption.
The lake’s waters had receded and dried up portions of Pagsipit River, the lake’s only drainage outlet, owing to the continuous volcanic earthquakes, Bornas said at a press briefing on Wednesday. This indicated a rise or “uplifting” of the Taal region.
“It’s possible that the cracks seen in Lemery [in Batangas province] go straight to Talisay [the town near the lake]. There could be underwater fissures on the floor of the lake and water has seeped into them,” she added.
In general, this is all related to the ground deformation caused by magma pushing up the volcano, Bornas said.
Meanwhile, the local governments of Lemery, Agoncillo, and Laurel in Batangas province shut off their towns on Wednesday amid continued ashfall from Taal’s Sunday eruption.
Agoncillo Mayor Daniel Reyes told ABS-CBN he ordered a lockdown at 1 p.m., while Laurel Mayor Joan Amo closed the area at 5 p.m.
Lemery Mayor Eulalio Alilio said the town was placed under lockdown at 6 p.m. except Barangays Gulod, Arumahan, Talaga, Payapa Ilaya, Mayasang, Niugan, and some portions of Brgy. Payapa Ibaba.
Paolo Reniva, PHIVOLCS resident volcanologist and Taal Observatory officer in charge, also warned of threats of pyroclastic density currents that could kill people and destroy property along shoreline communities near the volcano island.
In an interview over GMA-7’s Unang Balita, Reniva also told residents of Laurel and Agoncillo municipalities that a volcanic tsunami could ensue.
“A strong eruption could cause some parts of the volcano to collapse and displace the water in it, then the water would plunge into the shorelines,” he said.
Just like the 1965 Taal Volcano eruption, a base surge and volcanic tsunami would affect Laurel and Agoncillo, he added.
PHIVOLCS said a hazardous volcanic eruption is when Taal Volcano would exhibit horizontally moving clouds over 60 kilometers per hour.
According to Solidum, the occurrence of volcanic earthquakes is the primary parameter in raising the alert level for active volcanoes, such as Taal.
A high level of sulfur dioxide cannot be a good gauge if an explosive eruption could happen soon, he added.
The quakes and ground fissures in several barangays in Batangas indicated the continuous magmatic intrusion beneath the volcano, he said,
While Taal volcano is having a “generally weaker eruption” at the main crater, the cracks within its areas would only mean the volcano is very much active underneath with magma rising, he said.
In its 8 a.m. bulletin, PHIVOLCS said there were 466 volcanic earthquakes recorded since Jan. 12.
New ground fissures or cracks were observed in Lemery’s barangays Sinisian, Mahabang Dahilig, Dayapan, Palanas, Sangalang, Poblacion and Mataas na Bayan; Agoncillo’s barangays Pansipit and Bilibinwang; Talisay’s barangays Poblacion 1, Poblacion 2, Poblacion 3 and Poblacion 5, and San Nicolas’ Barangay Poblacion.
Meanwhile, more military personnel were sent to various areas in Batangas and Cavite provinces to hasten the movement of thousands of displaced residents and support their daily routine following Sunday’s eruption of Taal Volcano.
The additional military forces were deployed to provide humanitarian assistance to thousands of residents who had to be moved to a safer place.
Even Army reservists from the 401st and 402nd Ready Reserve Infantry Battalions of the 4th Regional Community Defense Group of the Army Reserve Command have also been mobilized to assist in crowd control in evacuation centers and help local government units and agencies to distribute relief goods.
“Even before the eruption of Taal Volcano on Sunday afternoon, we already have reservists on the ground monitoring the situation. So, as soon the evacuation efforts started, our reservists were able to immediately provide their assistance,” said Lt. Col. Ruperto B. Chua (Res), Commander of 401st Ready Reserve Infantry Battalion.
Communication equipment were also installed in strategic areas in volcano-affected municipalities to boost the ongoing military humanitarian assistance.
The Philippine Air Force has also sent two Huey Helicopters in Batangas and conducted aerial surveys and inspection to determine the extent of damage brought by the eruption. With Francisco Tuyay