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Mayon Volcano, also known as Mount Mayon, is an active stratovolcano in the province of Albaymarker, in the Bicol Regionmarker, on the island of Luzonmarker, in the Philippinesmarker.

Renowned as the "Perfect Cone" because of its almost perfectly conical shape, Mayon is situated 15 kilometres northwest of Legazpi Citymarker.

A level 2 alert is in force for Mayon because of increased activity in June-July 2009.

On 13 October,2008 it was included in New7Wonders of Nature Top 10 list. However, it didn't make the cut to the Top 25 finalists, giving way to Puerto Princesa Subterranean River, another site in the Philippinesmarker.

Geomorphology

Mayon Volcano is an active stratovolcano. The current cone was formed through pyroclastic and lava flows from past eruptions. Mayon is the most active of the active volcanos in the Philippines, having erupted over 49 times in the past 400 years.

It is located on the eastern side of Luzonmarker, beside the Philippine Trench which is the convergent boundary where the Philippine Sea Platemarker is driven under the Philippine Mobile Belt. Where a continental plate or belt of continental fragments meets an oceanic plate, the lighter continental material overrides the oceanic plate, forcing it down into the earth's mantle. Magma, formed where the rock melts, may be forced through weaknesses in the continental crust caused by the collision of the tectonic plates. One such exit point is Mayon.

Like other volcanoes located around the rim of the Pacific Ocean, Mayon is part of the Pacific Ring of Fire.

Location and formation



Mayon Volcano is the main landmark of Albay Provincemarker, Philippines. It is ten kilometres (6 mi) from the Gulf of Albay,in the municipalities of Legazpi Citymarker, Daraga, Camaligmarker, Guinobatanmarker, Ligao Citymarker, Tabaco Citymarker, Malilipotmarker, and Santo Domingomarker (clockwise from Legazpi). It rises 2462 m (8,077 ft) above the gulf.

Mayon Volcano is the Philippines' most active volcano and is considered to be the world's most perfectly formed volcano for its symmetrical cone. It is a basaltic-andesitic volcano. 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.

Recorded eruptions

Mayon Volcano in the hemp-producing district of Luzon as depicted in history and conquest of the Philippines and our other island possessions; embracing our war with the Filipinos by Alden March, published in 1899.
Caption (cropped out) read: "This is said to be the most beautiful volcano in the world.
It is 8,223 feet high, its shape is a perfect cone and its crest is always fiery.
It has indulged in several destructive eruptions.
In 1814 many houses were destroyed and 2500 people were killed and wounded.
At its base are famous springs of great medicinal value".


Mayon has had forty-nine eruptions in recorded history. The first recorded eruption was in 1616, the last major eruption ceased on 1 October 2006, although a devastating lahar followed on 30 November 2006. A further summit eruption occurred on 10 August 2008.

Mayon Volcano on September 23, 1984


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 Cagsawamarker—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 in depth. 2,200 Albay locals perished in what is considered to be the most lethal eruption in Mayon's history.

Mayon Volcano's longest uninterrupted eruption occurred on June 23, 1897 which lasted for seven days of raining fire. Lava once again flowed down to civilization. Seven miles eastward, the village of Bacacay was buried beneath the lava. In Libog, 100 people were declared dead—incinerated by steam and falling debris or hot rocks. 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 people were killed.

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 overlooks a peaceful pastoral scene approximately five months before the volcano's violent eruption in September 1984.


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.

Pyroclastic flows killed 77 people, mainly farmers, in Mayon’s fatal eruption of 1993.

2006 activity

Mayon erupted again from July to October 2006, with no apparent loss of life during the actual eruption period.

On 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 Philippines Institute of Volcanology and Seismology (Phivolcs), which warned that pyroclastic flows or an explosive eruption could occur any time.

On 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. Volcanologists have detected 21 low-frequency volcanic earthquake since early Sunday morning.

On 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.

Mayon Volcano as seen from space.


On 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.

On 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.

On 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.Phivolcs maintained 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.

On September 11, 2006 Phivolcs downgraded 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".

On October 3, 2006 Phivolcs downgraded 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."

On October 25, 2006 Phivolcs downgraded threat level to Alert Level 1 (no hazardous eruption imminent).

Phivolcs did not issue any further alerts or updates for Mayon in November or December 2006.

Devastating aftermath

On November 30, 2006, Typhoon Durian caused mudslides of volcanic ash and boulders from the slopes of Mayon Volcano, killing an estimated 1,000 and covering a large portion of the village of Padang (an outer suburb of Legazpi Citymarker) in mud up to the houses' roofs.

The number of dead was estimated at around 1000, about half the death toll of the 1814 eruption. The precise figure may never be known since many people were buried under the lahars, and entire villages disappeared.

Parts of Daraga were also devastated, including the Cagsawa area, where the ruins from the eruption of 1814 were partially buried once again. Large areas of Guinobatanmarker were destroyed, particularly Maipon.

Students from Aquinas University in Barangay Rawis of Legazpi City were among those killed as mudslides engulfed their dormitory. Central Legazpi escaped the mudslide but suffered from severe flooding and power cuts.

2008 Eruption

On 10 August 2008, a summit explosion ejected ash 200 metres above the summit, with the ash drifting ENE. In the weeks prior to the eruption, there was a visible glow within the crater, and increased seismicity.

2009 activity

On 10 July 2009, PHIVOLCS issued the following bulletin:

This is a notice for the raising of Mayon Volcano’s status from Alert Level 1 (low level unrest) to Alert Level 2 (moderate unrest).

Beginning June 2009 monitored parameters indicated an increase in the current activity of Mayon Volcano. The number of recorded low frequency volcanic earthquakes rose to a higher level signifying possible movement of magma beneath the volcano edifice at shallow depth. The present seismic count is at the same level when a phreatic explosion occurred last August 2008. Ground uplift of about one centimeter was measured by Precise Leveling Survey conducted last June 15-22, 2009 and the uplift was sustained during a re-survey yesterday, July 9, 2009. Glow at the summit crater has intensified and could now be observed at Lignon Hill Observatory without the aid of telescopes. Steam emission was at moderate level.

Aerial survey conducted last July 08, 2009, showed a cone-shaped pile of hot, steaming old rocks, possibly remnants from previous eruptions which could be the source of the glow at the crater. The low frequency volcanic earthquakes and ground uplift could indicate that fresh volcanic materials are moving upward at depth, causing the formation of the cone-shaped pile of materials at the crater.

Because of the above observations, PHIVOLCS is now raising the Alert status of Mayon Volcano from Alert Level 1 to Alert Level 2. This alert condition signifies, a state of unrest which could lead to ash explosions or eventually to hazardous magmatic eruption. Thus, at Alert Level 2, PHIVOLCS strongly recommends that the 6-km radius Permanent Danger Zone (PDZ) around the volcano and the 7-km Extended Danger Zone (EDZ) on the southeast flank of the volcano are off-limits due to the threat from sudden explosions and rockfalls from the upper slopes. Active river channels and those areas perennially identified as lahar prone in the southeast sector should also be avoided especially during bad weather conditions or when there is heavy and prolonged rainfall.

On 20 July 2009 National Disaster Coordinating Council (NDCC) executive officer Glenn Rabonza issued a memorandum ordering regional and provincial disaster management agencies to closely monitor Mayon and Taal volcanoes.

"You are hereby directed to undertake monitoring and precautionary measures in your areas of responsibility. The public and the Disaster Coordinating Council concerned are advised to take appropriate actions and to be on alert for any development," the memorandum said.

Based on the Philippine Institute of Volcanology and Seismology (Phivolcs) alert levels chart for Mayon, Alert Level 1 is hoisted when there is a slight increase in seismicity and sulfur dioxide (SO2) gas output above the background level and when a very faint glow of the crater may occur but no conclusive evidence of magma ascent. At this stage, there is no danger of imminent eruption, but people are not allowed to enter the 6-km radius permanent danger zone (PDZ).

At 5:32 am Wednesday 28 October 2009, a minor ash explosion occurred in the summit crater lasting for about one minute. A brown ash column rose about 600 meters above the crater and drifted toward the northeast. In the prior 24-hours 13 volcanic earthquakes were recorded. Steam emission was at moderate level, creeping downslope toward the southwest. Phivolcs maintained the Alert Status at Level 2, but later warned that with the approach of tropical cyclone international codename Mirinae the danger of lahars and possible crater wall collapse will greatly increase and all specified precautions should be taken.

At 1:58 am Wednesday 11 November 2009, a minor ash explosion occurred at the summit crater lasting for about 3 minutes. This was recorded by the seismic network as explosion type earthquake with rumbling sounds. Incandescent rock fragments at the upper slope were observed in nearby barangays. Ash column was not observed due to cloud cover. After dawn field investigation showed ashfall had drifted southwest of the volcano. In the 24 hour period the seismic network recorded 20 volcanic earthquakes. Alert Status was kept at Level 2 indicating the current state of unrest could lead to more ash explosion or eventually to hazardous magmatic eruption.

Gallery

Image:Mayon 1926.jpg|Mount Mayon (1926)Image:Mayon Legaspi 1928.jpg|Mount Mayon on June 27, 1928, looming above LegaspiImage:Mayon 1928 1.jpg|Mount Mayon in eruption on July 21, 1928.Image:Mayon Volcano 1.jpg|Mount Mayon 2004Image:MayonVolcano.jpg|Mount Mayon. Uploaded 9/2006.Image:Airport Parking Area.jpg|Mount Mayon from Legaspi airport. Uploaded 10/2006.

References

External links




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