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Science The controversial sale of 'Big John,' the world's largest Triceratops. Entry into the island as well as high-risk barangays of Agoncillo and Laurel is prohibited. In addition, communities around the Taal Lake shore are advised to take precautionary measures and be vigilant of possible lake water disturbances related to the ongoing unrest.
As of 1 July, residents from barangays inside the seven-kilometre danger zone are being evacuated. Since the phreatomagmatic event earlier this afternoon, four 4 short phreatomagmatic bursts have occurred that lasted not longer than two 2 minutes each and produced short jetted plumes that rose meters above the Main Crater Lake.
The Alert Level 3 status of Taal means that there is ongoing magmatic extrusion at the Main Crater that may further drive succeeding explosions. All activities on Taal Lake should not be allowed at this time. Diffuse steam plumes from fumarolic vents in Main Crater rose only 5 m. Sulfur dioxide emissions were 1, tonnes per day on 10 March, and fluctuated between and tonnes per day through 14 March.
At on 12 March a short-lived 2. Diffuse steam plumes rose 50 m above fumarolic vents on the inner N and E walls during the rest of the day. The number of volcanic earthquakes per day rose to 74 during March and to during March. Episodes of tremor persisted, with periods recorded per day.
Five hybrid events were detected during March. Sulfur dioxide emissions were 1, tonnes per day on 15 March. Steam emissions rose 10 km during March. The seismic network recorded 42 volcanic earthquakes and 34 periods of tremor. During March the seismic network recorded a total of 28 volcanic tremor events, four low-frequency volcanic earthquakes, and one hybrid event at depths of less than 1.
These events added to the totals of volcanic tremor events and low-frequency volcanic earthquakes recorded during 13 February-9 March. Overall, seismicity over the past month indicated increased magmatic and hydrothermal activity at shallow depths beneath Taal Volcano Island TVI. The data also showed slow and steady inflation across the Taal region after the eruption. Microgravity data was consistent with magma migration. A maximum temperature of Tilt data indicated minor deflation around Main Crater, though minor inflation was consistently recorded across the Taal region as indicated by analysis of GPS data, InSAR, and microgravity changes.
A total of 68 relatively weak tremor signals were detected during February; 50 of those were recorded during on 15 February. The events on 15 February ranged in duration from two to five minutes and occurred at depths less than 1 km. The depth and location of the earthquakes suggested increased hydrothermal activity beneath Taal Volcano Island. Increased seismic activity continued through 16 February; from on 15 February to on 16 February there were a total of 98 earthquakes.
According to the Disaster Response Operations Monitoring and Information Center DROMIC there were a total of 4, people in 11 evacuation centers, and an additional 17, displaced people were staying at other locations as of 11 March.
On 14 February PHIVOLCS lowered the Alert Level for Taal to 2 on a scale of noting a decline in the number of volcanic earthquakes, stabilizing ground deformation of the caldera and Volcano Island, and diffuse steam-and-gas emission that continued to rise no higher than m above the main vent during the past three weeks.
Sulfur dioxide emissions ranged from values below detectable limits to a high of tonnes per day on 8 February. Weak steaming plumes m high from ground cracks was visible along the Daang Kastila trail which connects the N part of Volcano Island to the N part of the main crater. Sulfur dioxide emissions ranged from values below detectable limits to a high of tonnes per day on 3 February. Both the number and magnitude of volcanic earthquakes declined; by 21 January hybrid earthquakes had ceased and both the number and magnitude of low-frequency events had diminished.
The rate of the deformation patterns was smaller during January, and generally corroborated by field observations; Taal Lake had receded about 30 cm by 25 January but about 2. Sulfur dioxide emissions were low at tonnes per day on 22 January but averaged around tonnes per day through 26 January; emissions were 87 tonnes per day on 27 January and below detectable limits the next day.
Activity during January was characterized by dark gray, steam-laden plumes that rose as high as 1 km above the vents in Main Crater and drifted S and SW. Satellite images showed that the Main Crater lake was gone, and new craters had formed on the floor and N flank of Volcano Island. Sulfur dioxide emissions were 4, tonnes per day on 15 January. Sulfur dioxide emissions fluctuated and were as high as 4, tonnes per day on 20 January and as low as tonnes per day on 21 January.
From on 12 January to on 21 January the Philippine Seismic Network PSN had recorded a total of volcanic earthquakes; of those had magnitudes ranging from 1. The Alert Level remained at 4 on a scale of A seismic swarm beneath Taal began at on 12 January and a phreatic eruption commenced at The initial eruptive activity was characterized by increased steaming from at least five vents in Main Crater and phreatic explosions that generated m-high plumes.
Activity escalated at ; volcanic tremor and earthquakes felt locally were accompanied by an eruption plume that rose 1 km. Ash fell in the SSW part of Taal. The eruption plume of steam, gas, and tephra significantly intensified and rose km 32,, ft a. Wet ash fell in areas downwind, including as far N as Quezon City 75 km.
About 6, people had been evacuated but the number was expected to rise. The eruption progressed to a magmatic eruption during on 13 January, characterized by weak lava fountaining accompanied by thunder and flashes of lightning. Activity briefly waned then resumed with sporadic weak fountaining and explosions that generated 2-km-high, dark gray, steam-laden plumes.
News articles noted that more than domestic and international flights were cancelled as the Manila Ninoy Aquino International Airport was closed during January; some flights could depart in the early afternoon of 13 January. Authorities continued to evacuate high-risk areas within a km radius of Taal; by 13 January more than 24, people had moved to 75 shelters out of a total number of , people within 14 km.
By lava fountaining generated m-tall, dark gray, steam-laden plumes that drifted SW. Since on 12 January the seismic network had recorded a total of volcanic earthquakes, with of those felt with Intensities of I-V. Satellite images showed that the Main Crater lake was gone and new craters had formed inside Main Crater and on the N flank.
PHIVOLCS reported that during the previous 11 weeks, since the Alert Level for Taal was raised to 2 on a scale of on 9 April, the number of earthquakes recorded daily gradually declined, hydrothermal activity abated, carbon dioxide gas emissions decreased, ground temperature and total magnetic field measurements in the main crater showed no significant changes, and deformation data showed no signs of increasing pressure.
On 5 July the Alert Level was lowered from 2 to 1. During May, between 6 and 10 daily volcanic earthquakes were detected by the seismic network. Some of the earthquakes were felt by nearby residents on the SE part of the island. During May, earthquakes were recorded.
During May there were 31 earthquakes noted. Some of the earthquakes were felt by nearby residents. Results of a ground deformation survey conducted around Volcano Island during April showed that the edifice was slightly inflated compared to a survey from early February. According to news articles, the number of people that had evacuated from around Taal rose to 1, The water level had receded 3 mm and the water temperature slightly increased from 30 to Since the previous measurement on 29 March, the pH value increased indicating that the water had become slightly less acidic.
Gas measurements conducted last January, February, and March yielded carbon dioxide emission values in tonnes per day of 2,, 1,, and 4,, respectively. Steaming at the N and NE sides of the main crater occasionally intensified and was occasionally accompanied by hissing sounds. The Alert Level was raised to 2 on a scale of because of increased seismicity and carbon dioxide emissions.
According to news articles, about families had volunteered to evacuate; about 7, people remained. Field observations during January revealed an increase in the number of steaming vents inside Main Crater and a drop in the lake level. The lake water temperature and pH values were normal. Visual observations on 27 January showed that steaming at a thermal area in the crater was weak.
The Alert Level remained at 1 on a scale of Temperature and acidity of the lake were at normal levels, and the color had not changed. During January, up to seven daily volcanic earthquakes were detected by the seismic network. Field observations on 10 January revealed no significant changes. Weak steaming from a thermal area inside the main crater was noted and the lake temperature and color were normal.
During January 10 volcanic earthquakes were detected; two earthquakes were felt by residents in barangay neighborhood Pira-piraso, on the N side of the island. On 17 January three volcanic earthquakes were detected and on 18 January only one was reported. Temperature measurements of the main crater lake did not increase further since 8 June, remaining between and degrees Celsius.
The number of earthquakes recorded daily gradually declined to background levels beginning the second week of July. Since 26 April the number of earthquakes per day continued to increase, as well as the magnitude. Low-frequency volcanic earthquakes were detected on 2 June, and during the previous day high-frequency earthquakes were noted.
In addition to increased seismicity, the temperature of the Main Crater Lake increased from 32 degrees Celsius on 11 May to 34 degrees Celsius on 24 May. Deformation data had shown slight inflation since ; measurements taken at the SE side of Taal on 7 June showed further inflation by 3 mm. Ten earthquakes occurred; two at Intensity II were felt by residents in the Pira-Piraso village and were accompanied by rumbling sounds.
The earthquakes were located NE of the island near the Daang Kastila area at estimated depths of 0. Surface observations indicated no change in the main crater lake area. The Alert Level remained at 1 scale is , 0 referring to No Alert status.
According to news articles, geysers of muddy water m high occurred in the NNE portion of Taal's main crater during November. Approximately five seismic events in a hour period is typical during quiet periods.
The seismic network at Taal began to record significant volcanic earthquakes on 23 September. In general, through 29 October the number of earthquakes increased, with a maximum of 13 earthquakes recorded on 15 October. No significant changes in thermal and steam emissions were observed.
PHIVOLCS recommended appropriate vigilance by the public when visiting the island and noted that Main Crater was off-limits to visitors because of the potential for sudden steam explosions and high concentrations of noxious gases.
Click on the index link or scroll down to read the reports. Card 09 September Increased steaming from cone area. The following information was reported in the "Daily Mirror" on 31 August Arturo Alcaraz, chief volcanologist, said steaming activity has increased considerably on the base and slopes of the cone formed in the last eruption.
He also said that the steaming is very noticeable today from several areas of the lava flow in Kaygabok. Card 08 October Volcanic earthquakes and intensified surface thermal activity.
The following report was received on 7 October The volcanology commission reported last night that Taal volcano had entered another active period that could culminate in another eruption.
Seven volcanic quakes and tremors were recorded in a hour period. COMVOL observers on Volcano Island also reported that there was intensified surface thermal activity, confirming that the volcano's condition was abnormal. Volcanologist Nazario Vasquez reported that instruments have picked up seven volcanic quakes and tremors from Taal's depths, clearly indicating its restlessness. Vasquez said surface steaming, rise of temperature readings in all ground probe holes, and other intensified activity in the main crater lake may all culminate in another eruption.
Card 09 October Field and instrumental data indicate renewed activity. The following report was received from the American Embassy in Manila on 8 October Signs Taal volcano resurgence plainly inferred by existing field and instrumental data. Surface activity at cone has gained momentum. Despite absence rains for last two or three days which might have brought about condensation steaming and emission sulfuric vapors very strong this morning.
In addition, fresh slide scars attest volcano's restlessness as seismicity of island continued. Three more volcanic quakes picked up commissions seismograph; one on 7 October; another on 7 October, and third at on 8 October.
Card 11 October Increased seismicity; fresh rockslide at eruption cone. The following report was received from the American Embassy in Manila on 11 October Seismic activity again picked up rapidly.
For the hour period beginning on 9 October through on 10 October. Field observations conducted early this morning 10 October at the eruption cone disclosed fresh evidence of rock slide, indicating recent movement within the volcano. Chloride and sulfuric sublimate have spread almost throughout NW outer slope of cone.
Card 11 October High level of seismic activity returns. The following report was received from the Commission on Volcanology on 6 October Taal volcano shook more strongly the past 24 hours. The volcano is back to its high-level seismic activity, convulsing five times through Sunday morning. A quake recorded at on 6 October was big enough to have an amplitude of 17 mm. The usual amplitude of earthquakes at Taal volcano since it became restless again was mm.
Card 14 October Significant volcanic seismicity; steam emission intensifying. The following report was received from the American Embassy in Manila on 14 October As of 13 October the surface activity and seismicity were both weak for the last 48 hours. As of 14 October at the four-day seismic lull was broken by eight volcanic microseisms of appreciable magnitude. Crater lake temperature was decreasing, but steam emission was intensifying, especially at the SW shoreline of the lake.
Card 15 October High seismicity and surface thermal activity. The following report was received from the American Embassy in Manila on 15 October Taal status as of 15 October hours. High level of seismic disturbance. Intensification of surface thermal activity. Card 17 October Crater lake temperature increases 2. The following news report was received on 17 October The next heat reading, according to volcanologists here, exceeds that recorded in the same lake when Taal volcano erupted in This is, however, slightly lower than the heat reading of He said, however, that a bigger blast can be reasonably expected to occur because more volcanic energy will be needed this time to throw out tons of earth and lava blocking the exit.
Almoradie said aside from the heat rise, emission of steam in the southwestern shores of the main crater lake was observed to be intermittent occurring every five to ten minutes. He also said all the steam vents facing Binintian Malaki started emitting more steam and vapor this morning. Strict enforcement of precautionary measures under phase on of Operations Taal is now being observed.
Card 13 December Minor seismicity; eruptive activity anticipated. Anticipated second activity Taal about to commence. Small but continuing local vibrations recorded by Volcano Island seismograph. If persistent could bring expected eruptive activity.
Card 15 December Continuous tremor replaced by spasmodic earthquakes on 15 December. The continuous tremors have been replaced by spasmodic volcanic earthquakes often associated with crustal deformation. These developments suggest that the volcano's pent-up energy is trying to punch through and initiate an eruptive activity. As present indications point to a persistent pressure from below, the condition of Taal remains critical and a surface out-break of this pressure is perhaps just a matter of time.
Card 29 October Eruption of ash and incandescent fragments on 29 October. Taal eruptive activity commenced at on 29 October. Point of activity on upper outer southern slope of cone characterized by weak ejection ash and small fragmental materials at approximately minute intervals. COMVOL visual observation during afternoon showed appreciable increase in amount ash and fragmental red hot volcanic materials and considerable enlargement in diameter of active vent.
Increase in trace amplitude of harmonic tremors and explosion earthquake also noted. Night and early morning observations 30 October showed ejection of ash and fragments to heights of feet at about minute intervals. Continuing recording of harmonic tremors and observable pulsating vent flows seems to indicate vibration of lava to surface.
Eruption is now violent though protracted. The following is from the Commission on Volcanology via Father Hennessey. Taal Volcano erupted at on 29 October. Ashes and fragments were ejected up to feet at minute intervals shooting up from a roaring vent about 5 m in diameter.
During early hours of 30 October observations show sections of ash and incandescent fragments to feet at varying but closer intervals compared to previous observations. Proportion of incandescent material noted increased since yesterday. Continuous recording of harmonic tremors and observable pulsating dense flow seems to indicate that lava vibrating to the surface.
Continued production of lava flows and ejecta; new cone on SE flank. Card 05 November Erupting vent has enlarged; ejecta falling on upper slopes. The bits of molten rock from the surging column of lava are falling on the upper southeastern slope of the cone. Alcaraz, said that the coming eruption of Taal will not be of steam and ash but will be magmatic or cool lava. The volcano's pulsating magma has been surging with mounting intensity and frequency.
The erupting vent has been enlarged and now measures almost m in diameter. Taal's ejecta is being blown upward to a height of 1, feet. The lava column may surface in a few days, overflow, and fill the southeastern base of the cone. A protracted magma eruption might cover the thick lava deposits of the eruption in Kaygabok. Card 10 November New cone rapidly growing on the SE slope of the crater. The conelet is now about feet high. The cone's lava front advanced further into the collapsed lake on the Northeast.
The lava front is more than 1 km long and is moving at the rate of 1 m per minute. The stream may eventually flow into Lake Taal. Volcanologists said that harmonic tremors are getting stronger every day. The chief volcanologist, Mr. Alcaraz, said that this eruption is the second in recorded history where the volcano emitted more lava than ashes. The ejecta reached a height of 1, feet above the crater, which was widened to 20 m in diameter.
Card 19 November Sustained and copius ejection of ash and incandescent fragments; lava flows. The following is from the American Embassy in Manila. Ejecta has been primarily vertical but occasionally radial.
Yesterday's ejections accompanied by large detonation sounds and blue-tinted gas. Subterminal flows at base in terminal cone continue molten rock discharge at intensified rate to adjacent area. Front advanced into lake southwest of island. The following is from J. Evenings activity was more intense than that observed this morning.
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