SO2 Emissions picking up
Posted by JAC on 12/16/2009, 6:27 am






http://news.yahoo.com/video/world-15749633/17155674




Mayon Volcano Bulletin 3        
16 December 2009

8:00 AM

For the past 24 hours, Mayon Volcano's (13.2576 N, 123.6856 E) activity was characterized by quiet extrusion of lava and rolling down of incandescent lava fragments along Bonga gully. No explosion occurred. At present, the lava front reached about 700 m - 800 m downslope below the crater.  Lava fragments detaching from the lava pile inside the crater continuously  roll down along Bonga gully  reaching about 3 - 4 km downslope of the crater. Sometime, the detached lava fragments produced a small secondary  pyroclastic surge towards the southwest side of the volcano generating light ashfall in the municipalities of Camalig and Guinobatan. Seismic monitoring revealed the occurrence of seventy-eight (78) volcanic earthquakes and tremors. The volcanic earthquakes represent magma ascent towards the crater of the volcano while the tremors were associated to the detached fragments of lava and rockfalls. Emission of weak to moderate volume of white steam that reached height of 200 m above the summit and drifted towards southwest and west-southwest was observed during clear views of the crater yesterday. Measurement of Sulfur Dioxide (SO2) emission rate using FLYSPEC yesterday yielded a value of 750 tonnes per day (t/d).


The status of Mayon Volcano remains hoisted at Alert Level 3.  If trend is one of increasing unrest, hazardous volcanic eruption is possible within weeks. Thus PHIVOLCS-DOST considered 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 should be free from human activity because of sudden explosions that may generate hazardous volcanic flows. In addition, areas in the southeast that are outside the 7 kilometer danger zone but within 8 kilometers of the crater should be extra alert for increased volcanic activity.  Active river channels and those 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.  PHIVOLCS-DOST is closely monitoring Mayon Volcano's activity and any new significant development will be immediately posted to all concerned.



LEGASPI, Philippines (AFP) - Lava poured down the Philippines' Mayon volcano Wednesday as experts warned it could erupt for months, meaning thousands of villagers will spend Christmas in crowded evacuation centres.

Five small explosions were detected from Mayon on Wednesday morning, the last of which shot ash 500 metres (1,640 feet) into the air, government volcanologist July Sabit told AFP.

"Lava flow and lava fragments rolling down the volcano are continuous," Sabit said.

"It is part of the eruptive activity of the volcano. There is a high probability it will be like this for months."

Sabit cited Mayon's last eruption in 2006, when it emitted ash and oozed lava for two months.

The eruptions of 2006 did not claim any lives, but left huge deposits of volcanic ash on Mayon's slopes.

When Typhoon Durian hit the same area in December 2006, it caused a landslide of volcanic ash that killed more than 1,000 people.

The government has already evacuated about 23,000 people living in farming villages near the foot of Mayon and hopes to evacuate another 20,000 this week.

Most of the evacuation centres are at government schools, where classes have been called off.

Raffy Valenzuela, the civil defence chief for Albay province, where Mayon is located, said the makeshift camps were not yet up to standard.

"Some (schoolhouses) don't have sufficient bathrooms, others have... no running water. We are still fixing these things because this evacuation has been very sudden," he said.

Chief volcanologist Renato Solidum said that in the "worst-case scenario" of a major eruption, the government might have to evacuate another 15,000 families, or roughly 75,000 people.

Military trucks and even heavy trucks intended for construction projects are being used to evacuate the residents, Solidum said.

The government is ready to forcibly evacuate all villagers within the danger zone but there has been no resistance so far, he added.

The Mayon threat has come at a particularly inconvenient time of the year for the evacuees as they, like most of the other 92 million people in the predominantly Christian country, prepare for Christmas celebrations.

Defence Secretary Norberto Gonzales, who is in charge of disaster preparations, conducted an aerial survey of the volcano using a military helicopter on Wednesday.

He promised to distribute thousands of face masks to villagers to protect them from the effects of any volcanic ashfall.

The Philippine Institute of Volcanology and Seismology raised the alert level for Mayon to three on Monday after lava was seen spewing from the crater, and evacuations began immediately.

Level three on the five-point scale means a hazardous eruption is likely in the very near future.

Mayon, which sits above a farming area about 330 kilometres (200 miles) southeast of Manila, has erupted 48 times since records began, claiming thousands of lives.

In 1814, more than 1,200 people were killed as lava buried the town of Cagsawa.

However the 2,460-metre (8,070-feet) volcano remains a popular tourist attraction, and is famous for its perfect cone.

The Philippines is part of the so-called Pacific "Ring of Fire" that is known for its volcanic activity. The Philippine volcanology institute lists 22 active volcanoes in the country.


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Philippines raises volcano alert, orders evacuation - JAC, 12/14/2009, 2:58 pm
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