As of the 17th of February, the Philippine Institute of Volcanology and Seismology (PHIVOLCS) has reported that Mayon volcano's seismic monitoring network detected two (2) volcanic earthquakes and eleven (11) rockfall events were detected by the seismic network. The seismic network recorded a total of twenty-six (267) volcanic earthquakes and fifty-seven (57) rockfall events (01 - 07 February 2010). With respect to Ground Deformation deflation. No change relative to 08-10 Nov. 2009 survey. Overall, the volcano remained inflated by five (5.0) mm. cumulative to February 2008 baseline data SO 2 Flux Reading: 1667 tonnes/day (12 Feb.) but otherwise at: 719 tonnes/day (11 Feb.), 425 tonnes/day (10 Feb. ), 447 tonnes/day (9 Feb.), 430 tonnes/day (8 Feb.). Steaming activity was obscured and crater glow was at Intensity II
As of the 6th of February, PHIVOLCS reported that Mayon volcano's seismic monitoring network detected five (5) volcanic earthquakes and twelve (12) rockfall events were detected by the seismic network. The seismic network recorded a total of seventeen (17) volcanic earthquakes and sixty-nine (69) rockfall events (18 - 24 January 2010). With respect to Ground Deformation deflation. No change relative to 08-10 Nov. 2009 survey. Overall, the volcano remained inflated by five (5.0) mm. cumulative to February 2008 baseline data SO 2 Flux Reading: 1687 tonnes/day (28 Jan.) but otherwise at: 868 tonnes/day (26 Jan.), 288 tonnes/day (25 Jan. ), 1076 tonnes/day (24 Jan.), 1001 tonnes/day (23 Jan.). Steaming activity was moderate and crater glow was at Intensity I
As of the 29th of January, the Philippine Institute of Volcanology and Seismology (PHIVOLCS) has reported that Mayon Volcano's seismic monitoring network detected one (1) volcanic earthquakes and six (6) rockfall events were detected by the seismic network. The seismic network recorded a total of seventeen (17) volcanic earthquakes and sixty-nine (69) rockfall events (18 - 24 January 2010). With respect to Ground Deformation deflation. No change relative to 08-10 Nov. 2009 survey.
Overall, the volcano remained inflated by five (5.0) mm. cumulative to February 2008 baseline data SO 2 Flux Reading: 1213 tonnes/day (27 Jan.) but otherwise at: 868 tonnes/day (26 Jan.), 288 tonnes/day (25 Jan. ), 1076 tonnes/day (24 Jan.), 1001 tonnes/day (23 Jan.). Steaming activity was moderate and crater glow was at Intensity II. As of the 19th of january PHIVOLCS reported that the seismic network recorded a total of thirty (30) volcanic earthquakes and eighty-five (85) rock fall events. (11 - 17 January 2010).This day, Four (4) volcanic earthquakes and eight (8) rockfall events were detected by the seismic network.
As of the 15th of January, the Philippine Institute of Volcanology and Seismology (PHIVOLCS) has reported that Mayon Volcano's seismic network recorded 3 volcanic earthquakes and 13 rockfall events related to the detachment of lava fragments at the volcano's upper slopes during the past 24 hours. Steaming activity and crater glow were not observed due to thick clouds that covered the summit crater. Sulfur Dioxide (SO 2 ) emission rate was measured yesterday at an average of 635 tonnes/day.
As of the 12th of January, PHIVOLCS reported that six (6) volcanic earthquakes and seventeen (17) rockfall events related to the detachment of lava fragments at the volcano's upper slopes were detected by seismic monitoring network during the past 24 hours. Weak to moderate emission of white steam at the summit crater was seen during cloud breaks yesterday and early this morning. Pale crater glow was still observed last night. Yesterday's measurement of Sulfur Dioxide (SO2) emission rate yielded an average of 820 tons/day. Results of ground deformation measurements at Buang and Lidong precise leveling lines showed deflationary trend compared to 02 December 2009 survey. Alert Level 3 is still in effect over Mayon Volcano.
As of the 9th of January, the seismic monitoring network around Mayon Volcano detected five (5) volcanic earthquakes and twenty (20) rock fall events related to the detachment of lava fragments at the volcano's upper slopes during the past 24-hour observation period. Thick clouds covering the summit hampered visual observation during the day. However, an Intensity II crater glow was observed at nighttime during cloud breaks. Sulfur Dioxide (SO 2 ) emission rate was measured yesterday at an average of 1,345 tonnes/day.
As of the 8th of January, PHIVOLCS reported that Mayon Volcano's seismic monitoring network recorded five (5) volcanic earthquakes and twenty nine (29) rock fall events related to the detachment of lava fragments at the volcano's upper slopes during the past 24-hour observation period. Steaming activity and crater glow were not observed due to thick clouds that covered the summit crater. Sulfur Dioxide (SO 2 ) emission rate was measured yesterday at an average of 1,077 tonnes/day. As of the 5th of January, PHIVOLCS reported that three (3) volcanic earthquakes and twenty one (21) rockfall events related to the detachment of lava fragments at the volcano's upper slopes were detected by seismic monitoring network during the past 24 hours. Steaming activity and crater glow were not observed due to thick clouds that covered the summit crater. Sulfur Dioxide (SO 2 ) measurement was not conducted yesterday due to rain that occurred over the volcano area.
As of the 4th of January, PHIVOLCS reported that seismic monitoring network detected 7 volcanic earthquakes and 33 rockfall events related to the detachment of lava fragments at the volcano's upper slopes. Steaming activity was not observed due to thick clouds that covered the summit crater. Pale crater glow was observed last night. Sulfur Dioxide (SO 2 ) measurement was not conducted yesterday due to rain that occurred over the volcano area.
As of the 2nd of January 2010, PHIVOLCS reported that the seismic monitoring network around the volcano detected 13 volcanic earthquakes and 68 rockfall events related to the detachment of lava fragments at the volcano's upper slopes during the past observation period. Emission of weak volume of white steam at the summit crater was observed during cloud breaks yesterday. Sulfur Dioxide (SO 2 ) emission rate was measured yesterday morning at an average value of 2,621 tonnes/day. The latest activity of Mayon still indicates that its overall state of unrest remains relatively high. However, this phase of unrest, characterized by moderate seismicity, high volcanic gas outputs and continuing glow of the summit are processes normally associated with very gradual return to the repose period. The volcanic system is expected to continue producing earthquakes and to vent a large amount of gases because fresh magma still resides along the whole length of the volcanic pipe and near the summit. From 28 December to present, a declining trend in Mayon volcano's activity was noted as reflected by the following observations: 1. No ash ejections were observed since 29 December. Steam emission was most of the time weak and white in color indicating considerable decrease in energy and absence of ash. 2. Majority of the type of earthquakes that were recorded during the past days were associated with rockfalls and rolling down of fragments from the lava deposits along Bonga gully and the advancing lava front. 3. Measured SO 2 levels have also showed a decreasing trend from a maximum of 8,993 tons per day to 2,621 tons per day. The still high concentration of SO 2 gas emission suggests that there is residual magma degassing at shallow depth. In view of the above observations, PHIVOLCS-DOST is lowering the alert status of Mayon from Alert Level 4 to Alert Level 3 to reflect the overall gradual decrease of activity.
Previously, As of the 30th of December, PHIVOLCS reported that for the past 24 hours, one ash explosion occurred at Mayon Volcano (13.2576 N, 123.6856 E). The explosion produced a dirty white ash column that rose to about 100 meters above the summit and drifted to the northwest. Lava continued to flow down along the Bonga-Buyuan, Miisi and Lidong gullies. The lava front has now reached about 5.9 kilometers from the summit along the Bonga-Buyuan gully. Mayon Volcano's seismic network recorded 16 volcanic earthquakes. A total of 150 rock fall events related to the detachment of lava fragments at the volcano's upper slopes was also detected by the seismic network. Yesterday's measurement of Sulfur Dioxide (SO 2 ) emission rate yielded an average value of 4,397 tonnes per day (t/d). The volcano edifice remains inflated as indicated by the electronic tilt meter installed at the northeast sector of the volcano.
As of the 25th of December,PHIVOLCS reported that Mayon Volcano continued to show an intense level of activity during the previous 24-hour observation period. Ninety-six (96) ash explosions were observed during times of good visibility. These explosions produced light brown to grayish ash columns that reached heights of up to 2 km. One hundred twenty five (125) rumbling and booming sounds from the volcano were heard at the Lignon Hill Observatory in Legaspi City . Seismic activity remained elevated as the seismic network recorded a total of eight hundred seventy one (871) volcanic earthquakes. Ninety eight (98) rock fall events, related to detachment of lava fragments at the volcano's upper slopes, were also detected. Three of these events were observed to have generated pyroclastic flows that moved down within 2 km from the crater. Sulfur Dioxide (SO2) emission rate was high and was measured at an average of 2,738 tonnes/day yesterday.
As of the 23rd of December, bulletin of PHIVOLCS reported that Mayon Volcano continued to show an intense level of activity during the past 24-hour observation period. Seismic activity remained elevated in number and size as the seismic network detected 1,051 volcanic earthquakes and continuously recorded harmonic tremors. Many of these volcanic earthquakes were recorded at maximum deflection. Sixty six (66) ash explosions were observed during times of good visibility. These explosions produced grayish to light brown ash columns that reached height from 100 to 1000 meters above the summit before drifting towards southwest. Sulfur Dioxide (SO2) emission rate remained very high and was measured at an average of 6,737 tons per day (t/d) yesterday. Two hundred eighty (280) audible booming and rumbling sounds were intermittently heard for the past 24 hours. Red hot lava also continuously flowed down along the Bonga-Buyuan, Miisi and Lidong gullies.
As of the 21st of December, PHIVOLCS reports that activity escalated during the past 24-hour observation period. Seismic activity dramatically increased in number and size. A total of 1,942 volcanic earthquakes was detected by the seismic network. Many of these volcanic earthquakes were recorded at maximum deflection and continually occurred beginning at 12.21 yesterday. Harmonic tremors were also continuously recorded. Sulfur Dioxide (SO2) emission rate remained very high at 6,089 tonnes per day (t/d). Audible booming and rumbling sounds were first reported in the eastern flank of the volcano at about 1455H then occasionally occurred beginning 2200H last night. Intensified crater glow and rolling down of incandescent lava fragments from the crater was also persistent. Red hot lava also continuously flowed down along the Bonga-Buyuan, Miisi and Lidong gullies. Lava fountains rising approximately 200 meters above the crater were observed at 2007H, 2008H and 2018H. The lava front has now reached about 5 kilometers downslope from the summit along the Bonga-Buyuan gullies. Alert level is 4.
As of the 19th of December, PHIVOLCS reported that the volcano continued to exhibit intensified activity for the past observation period. A total of one hundred ninety seven (197) volcanic quakes and tremors were recorded by the seismic network. Eighteen (18) of these events were explosion type, however, only fifteen (15) were observed during times of good visibility. These explosions produced dirty white to grayish ash columns that reached height from 100 to 2000m above the summit before drifting towards southwest. Harmonic tremors were continuously recorded by the seismic instruments. During cloud break this morning, steaming activity ranged from dirty white to light brown in color. Night observation showed an intensified crater glow and continuous rolling down of incandescent materials from the crater. The advancing lava flow has now reached approximately 4 kilometers downslope from the crater along Bonga Gully. Sulfur Dioxide (SO2) emission increased from 1,065 to 2,034 tonnes per day (t/d).
As of the 17th of December, PHIVOLCS reports that two lava domes have formed at the crater of the volcano, raising concerns among government volcanologists over the possible extensive damage should these collapse and a major eruption occur. Renato Solidum, director of Phivolcs, said the domes were growing and that an aerial survey must be conducted to determine the hazards these would pose to residents living within the danger zone.
As of the 16th of December, PHIVOLCS reported that the volcano has continued to erupt lava and ash as thousands of people are evacuated from surrounding towns and villages. Phivolcs also reported glowing lava fragments continually being ejected onto the upper and middle slopes of the volcano. The head of disaster relief for eastern Bicol region has reported that ash explosions have reached heights of 1000 metres. Mandatory evacuations of around 10,000 families from within Mayon's 6-8 km danger zone have begun, with more than 20,000 people moved out so far. Ultimately around 50,000 people may need to be evacuated.
As of the 15th of December, PHIVOLCS reported that after lava began flowing from the crater earlier today, evacuations are under way around the Mayon volcano. A number of small ash explosions took place during the day, and the lava flows were reported from around 18:00 local time. At 20:00 local time the Phivolcs raised the alert level from 2 to 3. Mandatory evacuations of communities within the 6-8 km danger zone around Mayon will begin on Tuesday morning. Parts of the cities of Legazpi, Tabaco and Ligao, and the towns of Daraga, Camalig, Guinobatan, Santo Domingo, Bacacay, and Malilipot, fall within the danger zone: many thousands of people will be affected by the evacuations. Albay provincial authorities say that at least 9,000 families will be evacuated.
As of the 12th of December,PHIVOLCS reported that a small ash eruption occured on the evening of Friday 11 December 2009. The eruption occured at around 19:59 local time, and was preceded by rumbling sounds and about 50 earthquakes, felt by people living in nearby villages. Ash was ejected to an altitude of 0.5 km above the crater. As of the 3rd of December, PHIVOLCS repored that the volcano was calm for a week, but on Thursday shook and spat out sulfur dioxide. Instruments detected 18 volcanic quakes, of which eight were low and five were high- frequency earthquakes, indicating that magma was climbing up the volcano's vent. The volcano discharged 858 tons of sulfur dioxide in the past 24 hours, or above the normal 500 tons ejected by a restive volcano. Alert level 2 remains Mayon, a 2463-metre stratovolcano, is famous for the near-perfect symmetry of its cone, as well as its ability to unleash destructive eruptions, with hazards including pyroclastic flows, lahars and heavy ashfall. Particularly violent eruptions causing many deaths occurred in 1814 and 1897; more recently an eruption in September 1984 caused no fatalities after warnings from Philvolcs brought about the evacuation of more than 70,000 people from at-risk areas near the volcano.
Information : PHIVOLCS - Latest satelllite image of the Mayon (every 30 mn)
For more info and updates on the latest activity of Mayon Volcano, you may also visit National Disaster Coordinating Council and Philippine Institute of Volcanology and Seismology (PHILVOCS) .
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