TAAL VOLCANO ADVISORY

26 September 2006

11:00 A.M.

This is to notify the public and concerned authorities on the ongoing seismic unrest at Taal Volcano.

The Taal Main Crater Seismic Station recorded twenty nine (29) volcanic earthquakes during the past 24-hour period since 6: A.M. yesterday. Five (5) 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.  Initial earthquake locations showed epicenters generally dispersed in the vicinity of Daang Kastila (Northeast), Tibag (North), Tablas (Northeast), Mataas na Gulod (Northeast) and Panikihan (Northwest). This seismic activity is notably higher than the usual levels, which is generally only 5 or less events detected in 24 hours during quiet periods.

Surface thermal observations, however, 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.  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. The ongoing seismic unrest could intensify in the coming days or weeks so that PHIVOLCS recommends 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. There are also several fissures traversing the Daang Kastila Trail which, when reactivated with steam emission, are also potentially hazardous to people. PHIVOLCS will provide information on the status of Taal Volcano as necessary.