Taal spews ‘black jetted plume’ but major eruption still unlikely
LUCENA CITY—Communities in Batangas surrounding Taal Volcano continue to keep a close watch over the restive volcano after it had another minor phreatomagmatic eruption that produced a “black jetted plume” at noon on Saturday.
The Philippine Institute of Volcanology and Seismology (Phivolcs) said the phreatomagmatic eruption, which happens when water comes into contact with magma, at the volcano’s main crater occurred at 11:32 a.m. and lasted for four minutes.
“The event produced a short black jetted plume followed by a steam-rich plume that rose 2,000 meters above the main crater before drifting southwest,” the report said.
The volcano also had a phreatomagmatic eruption on Oct. 2 that lasted 11 minutes.
Phivolcs explained the phreatomagmatic event was “likely driven by sudden contact of water with a small branch of shallow magma that has been in place beneath the Taal Main Crater and that has been degassing sustained levels of SO2 (sulfur dioxide) for the past three years.”
Local government units close to the volcano were advised to continuously monitor and assess preparedness of their communities and undertake appropriate response measures to mitigate hazards that could be posed by long-term degassing and related phreatic activity.
Health risks
According to Phivolcs, the SO2 emissions logged in Taal Volcano since January this year remained high at an average of 6,673 tons a day.
“Degassing of high concentrations of volcanic SO2 continues to pose the threat of potential long-term health impacts to communities around Taal caldera that are frequently exposed to volcanic gas,” the agency warned.
Saturday’s phreatomagmatic event was preceded by at least five steam-driven eruptions, according to Phivolcs.
On Saturday, local authorities noted that traces of ashfall have been reported in parts of Agoncillo town, one of the localities that surround Taal Lake, along with the towns of Talisay, Laurel, Agoncillo, Sta. Teresita, San Nicolas, Alitagtag, Cuenca, Balete and Mataasnakahoy, and the cities of Tanauan and Lipa, all in Batangas province.
Officials in these towns and cities have previously asked residents to protect themselves from ashfall and sulfuric fumes by wearing face masks. In past instances of heavy ash falls, classes at all levels and work in government and private offices had been suspended in Taal’s lakeshore localities.
Agoncillo Mayor Cindy Valenton Reyes, on her Facebook page, on Saturday reminded the public “to remain calm but alert.”
On Thursday, President Marcos also assured the public that the government is ready to respond to any possible hazards of the eruption of Taal Volcano.
Taal has recorded 30 “minor eruptive events” since Sept. 22, the Phivolcs said.
On Friday, four phreatic or steam-driven eruptions were also detected that lasted from one to six minutes, the Phivolcs said.
The Phivolcs also detected two volcanic earthquakes accompanied by one volcanic tremor that lasted seven minutes during the past 24 hours until Saturday morning.
Alert levels
However, Phivolcs assured that the unrest now occurring in Taal was “unlikely to progress into a major magmatic eruption at this time.”
The volcano’s last big phreatomagmatic eruption happened on Jan. 12, 2020, which sent ashfall across many areas outside of Batangas.
On Saturday, volcanologists noted the continued “upwelling of hot volcanic fluids” along the main crater lake of the Taal Volcano Island, which is locally known as “Pulo,” which sits in the middle of Taal Lake.
“Should [the] phreatomagmatic activity at Taal persist or intensify, then the alert level may be raised to alert level 2,” said Phivolcs.
Alert Level 2 means “probable intrusion of magma at depth, which can lead to magmatic eruption.”
According to Phivolcs, entry to Taal’s permanent danger zone remained prohibited and that other areas within 5 kilometers of the active vent could be included in the danger zone.
As of Saturday, alert level 1 still prevailed over Taal Volcano (abnormal condition), which means that “sudden steam-driven or phreatic explosions, volcanic earthquakes, minor ashfall and lethal accumulations or expulsions of volcanic gas can occur and threaten areas within the Taal Volcano Island.” INQ
