Eight "very weak" phreatomagmatic bursts have been recorded in Taal Volcano on Saturday, Jan. 29, said the Philippine Institute of Volcanology and Seismology (Phivolcs).
In its advisory late Saturday night, Phivolcs said short phreatomagmatic bursts, which lasted only 10 seconds to two minutes, occurred between 3:50 p.m. and 9:57 p.m.
Phreatomagmatic burst occurs when hot magma comes into contact with groundwater.
Phivolcs said the "very short-lived" bursts "produced only traces in the seismic record but were accompanied by distinct infrasound signals."
However, the events generated steam-rich plumes between 400 meters and 900 meters high as detected by visual and thermal cameras around Taal Lake.
"Sulfur dioxide flux since the beginning of 2022 has averaged 10,668 tons per day, with the highest average emission at 18,705 tons per day on January 27, 2022," Phivolcs said.
Meanwhile, "almost no volcanic earthquake activity has been recorded since Dec. 19," it pointed out, adding that the volcano island has been deflating since October 2021.
Phivolcs said that Taal Volcano remains under alert level 2, which means that the volcano continues to manifest "increased unrest." The volcano has been under alert level 2 since July 23, 2021.
It warned that gas-driven explosions and lethal accumulations or expulsions of volcanic gas can occur and affect areas within and around the Taal Volcano Island.
Phivolcs reiterated that entry into the Taal Volcano Island, which is a permanent danger zone, especially the vicinities of the main crater and the Daang Kastila fissure, is strictly prohibited.
Boating and other activities on Taal Lake are also prohibited, Phivolcs said.
"Local government officials are advised to continuously assess and strengthen the preparedness of previously evacuated barangays around Taal Lake in case of renewed unrest," it added.