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TAAL VOLCANO BULLETIN, 06 April 2011, 8:00 A.M. PDF Print
Wednesday, 06 April 2011 06:41

Taal Volcano’s (14°00.1’N, 120°59.6’E) seismic network recorded five (5) volcanic earthquakes during the past 24 hours. Field observation and measurements conducted at the eastern sector inside the Main Crater Lake (via Calauit) on 5 April 2011 showed that steaming activity at the thermal area was weak. The water level further receded from 0.36 m to 0.33 m.  Water temperature slightly increased from 30.0°C to 30.5°C and pH value slightly increased to 2.84 as compared to the last reading of 2.82 on 29 March 2011 denoting that the water became slightly less acidic.  Gas measurements conducted at Taal Main Crater Lake last January, February and March 2011 yielded CO2 emission values of 2,250 tonnes per day (t/d), 1,875 tonnes per day (t/d) and 4,670 t/d respectively. The remarkable increase in C02 concentration indicates anomalous gas release from the magma at depth. Result of the ground deformation survey (precise leveling) conducted around the Volcano Island last 02-09 February 2011 showed that volcano edifice is slightly inflated as compared with the 15-23 December 2010 survey.

PHIVOLCS reiterates Alert Level 1 and its recommendation over Taal Volcano.  At present, no imminent eruption is indicated. However, the public is advised to strictly observe some safety precautions. PHIVOLCS reminds the general public that the Main Crater should remain strictly off-limits because sudden hazardous steam-driven explosions may occur and high concentrations of toxic gases may accumulate. Inhaling CO2 gas can cause negative effects such as headache, dizziness, muscular weakness and fainting.  Breathing air with high concentration can be lethal to human, animals and even cause damage to vegetation. The northern portion of the Main Crater rim in the vicinity of Daang Kastila trail, may also be dangerous when increase steam emission is reactivated along existing fissures.   Furthermore, the public is also reminded that entire Volcano Island is a Permanent Danger Zone (PDZ), and permanent settlement in the island is strictly not recommended.  DOST-PHIVOLCS is closely monitoring Taal Volcano’s activity and any new significant development will be immediately relayed to all concerned.