Mayon Volcano

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Mayon Volcano
Mayon Volcano as viewed from Lingñon Hill in Daraga, Albay
Elevation	2,463 metres (8,081 ft)
Location	Albay, Philippines
Coordinates	13°15′24″N 123°41′6″E / 13.25667, 123.685Coordinates: 13°15′24″N 123°41′6″E / 13.25667, 123.685
Type	Stratovolcano
Last eruption	2006

The Mayon Volcano is an active stratovolcano in the Philippines on the island of Luzon, in the province of Albay in the Bicol Region. The near perfectly cone shaped volcano is situated 15 kilometres northwest of Legazpi City.

Mayon is classified by volcanologists as a stratovolcano, or composite volcano. Its symmetric cone was formed through alternate pyroclastic and lava flows. Mayon is the most active volcano in the country, having erupted over 47 times in the past 400 years.^{[citation needed]} It is located between the Eurasian and the Philippine Plate, at a convergent plate boundary: where a continental plate meets an oceanic plate, the lighter continental plate overrides the oceanic plate, forcing it down; magma is formed where the rock melts. Like other volcanoes located around the rim of the Pacific Ocean, Mayon is a part of the "Pacific Ring of Fire".

1 Location and formation
2 Recorded eruptions
- 2.1 2006 activity
3 References
4 External links

[edit] Location and formation

Mayon Volcano in Albay showing its distance from the gulf

Mayon Volcano is the main landmark of Albay Province, Philippines. It is ten kilometres (6 mi) from the Gulf of Albay,^[1] in the municipalities of Legazpi City, Daraga, Camilig, Guinobatan, Ligao City, Tabaco City, Malilipot, and Santo Domingo (clockwise from Legazpi). It rises 2462 m (8,077 ft) above the gulf.^[2]

Mayon Volcano is the Philippines' most active volcano and is considered to be the world's most perfectly formed volcano^[1] for its symmetrical cone. It is a basaltic-andesitic volcano.^[2] The upper slopes of the volcano are steep averaging 35-40 degrees and are capped by a small summit crater. Its sides are layers of lava and other volcanic material.

[edit] Recorded eruptions

Mayon has had forty-seven eruptions in recorded history;^{[citation needed]} the first recorded eruption was in 1616, the latest (prior to 2006) being a mild outpouring of lava in June 2001.

The most destructive eruption of Mayon occurred on February 1, 1814. Lava flowed but not as much compared to the 1766 eruption. Instead, the volcano was belching dark ash and eventually bombarding the town with tephra that buried the town of Cagsawa—only the bell tower of the town's church remained above the new surface. Trees were burned; rivers were certainly damaged. Proximate areas were also devastated by the eruption with ash accumulating to 9 m (30 ft) in depth. 2,200 Albay natives perished in what is considered as the most lethal eruption in Mayon's history.^[1]

Mayon Volcano's longest eruption occurred on June 23, 1897 which lasted for seven days of raining fire. Lava once again flowed down to the civilization. Seven miles eastward, the village of Bacacay was buried 15 m (50 ft) beneath the lava. In Libog, 100 people were declared dead—incinerated by steam and falling debris or hot rocks. The other villages like San Roque, Misericordia and Santo Niño became deathtraps. Ash was carried in black clouds as far as 160 km (100 mi) from the catastrophic event. More than 400 persons were killed.^[1] Samuel Kneeland, a professor and a geologist had observed the volcanic activity five months before the eruption. Kneeland was amazed with the beauty of Mayon:

Mayon Volcano on 23 September 1984

“ At night the scene was truly magnificent and unique. At the date of my visit the volcano had poured out...a stream of lava on the Legaspi side from the very summit. The viscid mass bubbled quietly but grandly, and overran the border of the crater, descending several hundred feet in a glowing wave, like red-hot iron. Gradually, fading as the upper surface cooled, it changed to a thousand sparkling rills among the crevices, and, as it passed beyond the line of complete vision behind the woods near the base, the fires twinkled like stars, or the scintillions of a dying conflagration. More than half of the mountain height was thus illuminated. ”

^[1]

No casualties were recorded from the 1984 eruption after more than 73,000 people were evacuated from the danger zones as recommended by scientists of the Philippine Institute of Volcanology and Seismology.^[3] Pyroclastic flows killed 77 people, mainly farmers, in Mayon’s last fatal eruption in 1993.

[edit] 2006 activity

July 18, 2006: The number and size of incandescent rockfalls from the active lava dome, as well as sulfur oxide emissions, increased, according to the Philippine Institute of Volcanology and Seismology, which warned that pyroclastic flows or an explosive eruption could occur any time.
August 7, 2006: The Philippine government ordered the evacuation of about 20,000 people living near the volcano, stating that an eruption was feared soon^[4]. Volcanologists have detected 21 low-frequency volcanic earthquakes since early Sunday morning.^[5]
August 8, 2006: The government expected to move some 34,276 people to 31 state-run shelters and warned that the mountain could explode at any time. ^[6] ^[7]

Mayon Volcano as seen from space.

August 9, 2006: Volcanologists warned that Mount Mayon could explode at any time but that the gravitational pull of a full moon could provide the final push. A full moon coincided with at least three of Mayon’s nearly 50 explosions over the last four centuries, including the two most recent in 2000 and 2001. Nearly 40,000 people have been moved from an 8 km (5 mi) danger zone on the southeast flank of the volcano, which has been quaking and spitting plumes of ash since July.^[8]
August 10, 2006: Scientists in the Philippines renewed warnings of a major explosion at the Mount Mayon volcano, describing a sudden period of quiet as "ominous". A drop in gas emissions and earthquakes sparked fears that the crater had plugged itself, increasing the likelihood of an explosive eruption. ^[9]
August 11, 2006: Scientists said ground surveys showed Mayon was still "swollen" and registered a high number of volcanic earthquakes, emitted large amounts of sulfur dioxide gas and continued to eject lava down its slope nearly four weeks after it came to life in a "quiet" eruption on July 14.^[10]

Philippines Institute of Vulcanology and Seismology (Phivolcs) maintains threat level at Alert Level 4 for the next month due to the continued extrusion of lava, ash explosions, steam and smoke plumes, seismic activity, and threat of further eruption.

September 11, 2006 Philippines Institute of Vulcanology and Seismology (Phivolcs) downgrades threat level to Alert Level 3. "After the ash explosion of 01 September, a general decline in the overall activity of Mayon has been established. The decrease in key parameters such as seismicity, gas (Sulfur Dioxide) emission rates and ground inflation all indicate a waning condition. The slowdown in the eruptive activity is also evident from the decrease in intensity of crater glow and the diminishing volume of lava being extruded from the summit". ^[11]
October 03, 2006 Philippines Institute of Vulcanology and Seismology (Phivolcs) downgrades threat level to Alert Level 2. "All monitored key parameters such as earthquake levels, ground deformation and gas outputs further declined. In addition, lava extrusion apparently ceased on 01 October 2006 as reported by Ligñon Hill Observatory. The above observations indicate the absence of an intruding new mass of magma." ^[12]
October 25, 2006 Philippines Institute of Vulcanology and Seismology (Phivolcs) downgrades threat level to Alert Level 1 (no hazardous eruption imminent). ^[13]
November 30, 2006: Typhoon Durian created mudslides of volcanic ash and boulders off of Mayon Volcano, killing hundreds and covering a large portion of the village of Padang (a barangay of Legazpi City) in mud up to houses' roofs.^[14] ^[15] The number of dead will never be known since many people are buried under the lahar and whole villages have disappeared, but is thought to be about 1000. The Cagsawa area of Daraga was hit hard, the ruins from the eruption of 1814 were covered again. Much of Guinobatan was destroyed, particularly Maipon. Aquinas University in Barangay Rawis of Legazpi City was hit, some students were buried by lahar in their dormitories.