Volcanologists report 'seismic unrest' at Taal Volcano

Just as Mayon Volcano appeared to be calming down, Taal Volcano in Batangas is now undergoing "seismic unrest," state volcanologists said Wednesday. In an advisory dated Sept. 26 but posted only Wednesday, the Philippine Institute of Volcanology and Seismology (Phivolcs) noted an increase in earthquakes at Taal Volcano. "The Taal Main Crater Seismic Station recorded 29 volcanic earthquakes during the past 24-hour period since 6 a.m. (Monday). Five of these quakes that occurred at 2:33, 2:34, 2:42, 2:47 and 2:49 a.m. were felt at Intensities II to III by residents on Volcano Island. These quakes were accompanied by rumbling sounds," it said. Phivolcs said the epicenters were dispersed in the vicinities of Daang Kastila (Northeast), Tibag (North), Tablas (Northeast), Mataas na Gulod (Northeast) and Panikihan (Northwest). This seismic activity, it added, is "notably higher" than the usual levels, which is generally only five or less events detected in 24 hours during quiet periods. On the other hand, Phivolcs said surface thermal observations did not indicate significant change in the thermal and steam emission manifestations of the Main Crater Lake area. "The increase in seismicity at Taal Volcano reflects a low-level episode of unrest. However, there is still no indication of an impending eruption," it said. Possible precursors, such as increased steam emission, increased temperatures of steam vents and other changes on the Main Crater Lake waters and of the ground are continuously being monitored, it said. Phivolcs recommended "appropriate vigilance" by the public when visiting the island. "As a safety measure, Phivolcs reiterates its previous recommendation that the Main Crater area remains off-limits because sudden steam explosions may occur or high concentrations of toxic gases may accumulate," it stated. "There are also several fissures traversing the Daang Kastila Trail which, when reactivated with steam emission, are also potentially hazardous to people," it advised. - GMANews.Tv