Kanlaon Volcano shows increased activity  

MANILA, Philippines — Residents and local government units (LGUs) on Negros Island have been advised to closely monitor Kanlaon Volcano as it has been showing increased seismic activity.

State seismologists said yesterday that they have recorded 41 volcanic earthquakes around the volcano’s summit since June 30.

The Kanlaon Volcano Network said the quakes included seven “very shallow tornillo signals” or earthquakes with low frequency, which could be associated with volcanic gas movements along the fractures on the upper slope.

The Philippine Institute of Volcanology and Seismology (Phivolcs) said that ground deformation data from continuous GPS measurements indicated a short-term slight inflation at the lower and middle slopes since January.

The inflation was consistent with the continuous electronic tilt recording along the southeastern flanks since the middle of March, Phivolcs said.

“The increased seismic activity and short-term ground deformation are likely caused by shallow hydrothermal processes that are happening beneath the edifice and could generate phreatic or steam-driven eruptions from the summit crater,” Phivolcs said in an advisory.

It reminded the public that Kanlaon is under Alert Level 1 or at low-level unrest.

“Entry into the four-kilometer-radius permanent danger zone is prohibited due to possibilities of sudden and hazardous steam-driven or phreatic eruptions,” Phivolcs said.