Kanlaon gas emission increases


The Philippine Institute of Volcanology and Seismology station in La Carlota City, Negros Occidental observed an increasing gas emission from the crater of Mt. Kanlaon between Feb. 11 and Feb. 13.

Engr. Andylene Quintia of Phivolcs, however, said there is nothing to worry since the parameters for the activity of the volcano remains to be in Alert Level 1.

Mt. Kanlaon remains in Alert Level 1 despite an increasing gas emission observed on Feb. 11 and Feb. 13. | NAB Photo

The increase in gas emission might have been triggered by the level of rain water at the crater brought about by the northeast monsoon. 

Since last year, the agency noted a slight inflation of the lower and middle slopes of the volcano, which may indicate hydrothermal or magmatic processes occurring deep beneath the edifice.

Quintia said that last Saturday, Phivolcs recorded 11 volcanic quakes and eight more on Sunday.

Phivolcs advised local government units with barangays at the foot of the volcano to strictly prohibit entry of individuals in the four-kilometer radius permanent danger zone since the recent activity based on the previous records might trigger phreatic eruption.

Since June last year, the volcano was placed under alert level one and has been off limits to trekkers.

The Kanlaon Green Brigade and the Department of Environment and Natural Resources Park Superintendent Office had been advised of the recent activity, Quintia said.

In an advisory issued Saturday night, Phivolcs said 28 volcanic earthquakes ranging from magnitudes 0.7 to 2.2 were recorded between Feb. 11 and Feb. 13. These occurred at a shallow depth of 10 kilometers.

Volcanic earthquakes are caused by movements or eruptions of magma from the volcano.

Sulfur dioxide gas emission from the summit crater on Saturday reached an average of 1,130 tonnes/day, the highest recorded this year, following a trend since June 2020 of emissions higher than background levels of 300 tonnes/day, the advisory added.

“(Mt. Kanlaon) is at alert level 1 (abnormal), but because of the increased volcanic earthquake activity in the past three days, increased gas emission Saturday, and continued slight inflation of the volcano slopes, we issued an advisory as it is more restive now than in past week,” Phivolcs director Renato Solidum Jr. said in a news report.

He added that this indicates increased possibility of phreatic eruptions (steam-driven explosion).

“Because of this, the public was reminded to be vigilant,” Solidum said. – MML