|TAAL VOLCANO BULLETIN 23 September 2011 8:00 A.M.|
|Friday, 23 September 2011 00:42|
Taal Volcano’s (14.0000°N, 120.9833°E) seismic network detected seven (7) volcanic earthquakes during the past 24 hours. Two of these events which occurred at 6:34 P.M. and 7:30 P.M. last night were felt at Intensity II by residents at Barangay Calauit in the southeastern part of the Volcano Island. Field measurements on 20 September 2011 at the eastern sector of the Main Crater Lake yielded slightly increased water temperature of 33.6°C from 33.5°C, water level at a steady 1.74 meters and more acidic pH of 2.72 from 2.79 as compared to previous readings. Ground deformation survey (precise leveling) on the Volcano Island last 21 - 28 July 2011 indicated that the volcano edifice is slightly deflated compared with 01 - 10 June 2011, but is nonetheless still inflated compared with baseline data. Baselines calculated from continuous GPS (Global Positioning System) data for the period February to August 2011 also recorded a very slight but steady inflation of the northeast flank of the Volcano Island. Carbon dioxide (CO2) emission recorded on 27 June 2011 at the Main Crater Lake was 1,821 tonnes per day, which is above background levels.
Alert Level 1 remains in effect over Taal Volcano. This means that hazardous eruption is not imminent. The public, however, is reminded that the Main Crater should be strictly off-limits because sudden steam explosions may occur and high concentrations of toxic gases may accumulate. The northern portion of the Main Crater rim, in the vicinity of Daang Kastila Trail, may also become hazardous when steam emission along existing fissures suddenly increases. Furthermore, the public is also reminded that the entire Volcano Island is a Permanent Danger Zone (PDZ), and permanent settlement in the island is strongly not recommended.