The ash column from the Mt Bulusan phreatic eruption on October 23, 2016 is 2.5 kilometers high.
© Ronald Ballon The ash column from the Mt Bulusan phreatic eruption on October 23, 2016 is 2.5 kilometers high.
Phivolcs records a phreatic eruption at 3:31 pm on Sunday, October 23, as the volcano in Sorsogon remains under Alert Level 1

Mt Bulusan, a restive volcano in Sorsogon province, again spewed ash on Sunday, October 23.

In a bulletin issued 5 pm on Sunday, the Philippine Institute of Volcanology and Seismology (Phivolcs) said a phreatic eruption occurred 3:31 pm, producing an ash column 2.5 kilometers high.

"The event was recorded as an explosion-type earthquake and lasted for approximately 15 minutes based on the seismic record," said Phivolcs.

"The eruption originated from the summit crater, while a smaller eruption also transpired at the southeast vent."

Phivolcs also said it recorded a total of 24 volcanic earthquakes since 5 am on Sunday.

A Mt Bulusan phreatic eruption is recorded on October 23, 2016.
© Phivolcs A Mt Bulusan phreatic eruption is recorded on October 23, 2016.
"This morning, prior to the eruption, a noticeable increase in sulfur dioxide emission to 578 tons/day was measured," it added. "Inflation was also recorded by continuous GPS measurements as of 30 September 2016, indicating pressurization beneath the volcano edifice."

Alert Level 1 remains in effect for Mt Bulusan, meaning there could still be more phreatic or steam-driven eruptions.

Phivolcs warned that entering the 4-kilometer Permanent Danger Zone (PDZ) around the volcano continues to be strictly prohibited.

Pilots are also advised not to fly close to Mt Bulusan's summit "as ash from any sudden phreatic eruption can be hazardous to aircraft."

The volcano's last magmatic eruption took place more than 40 years ago.