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Taal Volcano in Philippines Has Phreatic Eruption

Source info:

Author: Matt
Date: 2020-01-12 11:10:00
Blog: Volcano Science And News Blog
URL: http://feedproxy.google.com/~r/VolcanoScienceAndNewsBlog/~3/SlwcpJGoleI/taal-volcano-in-philippines-has.html

Summary:

TAAL VOLCANO in the Philippines has had a phreatic eruption, with plumes reaching approximately 1 km high. The eruption was preceded by volcanic tremor, which suggests that magma intrusion has interacted with the water table. The Philippines GMA News Online reports that the eruption occurred at about 11am local time.Three hours later, a stronger explosion occurred.The last major eruption of Taal occured in 1965, which sent pyroclastic flows and tsunami style waves through the lake which surrounds its currently active center. This was one of the Philippines most deadly eruptions.The current statement from PHIVOLCS is below: Several social media posts have shown first hand footage and imagery: The last historical eruption of Taal was in 1977 with a VEI of 2. The largest historical eruption occurred in 1965 with a VEI of 4, killing many.The new activity suggests there has been new magma injected into the system. This does not necessarily mean that a larger eruption is imminent, but it does typically mean that enough magma that has a heat flashpoint with water got close enough to flash water into steam, creating the latest explosion.Phreatic eruptions are the result of a minor (or major) volume of water coming into close contact with molten rock. The rock could be older 'crystal mush', or cooler magma which did not have enough gas content to erupt until it came into contact with a water source, or in rare cases fresh magma from the injection source.Taal volcano has been inflating, and the lake temperatures in the middle vents fluctuating, for years so this eruption is not entirely surprising. PHIVOLCS is monitoring the situation closely, and will be providing updates as soon as they can.In the last several minutes, it appears an even larger eruption is now underway. *****UPDATE 1/12/2020*****Lava fountaining is now observed in the main crater of Taal: Everyone on the central island has been evacuated. There is not currently an evacuation mandate for the residents around the larger lake (the central crater lake is now completely obliterated).The latest (Translated to English) update from PHIVOLCS:"DOST-PHIVOLCS indicates an increase in Alert Level 4 (hazardous eruption imminent) from Alert Level 3 (magmatic unrest) to the current status of the Long Range. Starting at 5:30 pm (PST), volcanic activity is intensified which includes continuous eruption of steam-laden tephra columns with a height of 10 to 15 kilometers with occasional lightning and rainfall. ash extends north of the volcano to Quezon City. Volcanic tremor was also recorded starting at 11:00 am, with two earthquakes of magnitude 2.5 (6:15 pm) and 3.9 (6:22 pm) in Tagaytay City and Alitagtag, Batangas in force Intensity III.In the event, DOST-PHIVOLCS raises Alert Level 4 to the state of the High Volcano where dangerous eruption is possible within hours to days. DOST-PHIVOLCS strongly recommends total evacuation from Taal Volcano Island and further evasion of hazardous or high-risk areas within a 14-kilometer radius from Taal Main Crater due to possible threat of having a pyroclastic density current (fast waves of very hot smoke and ash) and volcanic tsunami. Areas north of the Taal Volcano are advised to guard and beware of the effects of continuous and long-term rainfall. Civil aviation authorities should advise aircraft to avoid flying around the volcano because of the danger of ash and ballistic fragments from the eruption column. DOST-PHIVOLCS will continue to monitor the Taal Volcano's activity and release an update to the public."Next update:"Taal Volcano entered a period of intense unrest beginning with phreatic or steam-driven activity in several points inside the Main Crater at 1:00 PM of 12 January 2020 that progressed into magmatic eruption at 02:49 AM to 04:28 AM of 13 January 2020. This magmatic eruption is characterized by weak lava fountaining accompanied by thunder and flashes of lightning. At 2:00 PM yesterday, booming sounds were heard at Talisay, Batangas.The Philippine Seismic Network has recorded a total of seventy-five (75) volcanic earthquakes in Taal region as of 5:00 AM, January 13, 2020. Thirty-two (32) of these earthquakes were felt with intensities ranging from Intensity II – V in Tagaytay City, Cabuyao, Laguna, Talisay, Alitagtag, Lemery and Bauan, Batangas. Such intense seismic activity probably signifies continuous magmatic intrusion beneath the Taal edifice, which may lead to further eruptive activity. Alert Level 4 still remains in effect over Taal Volcano. This means that hazardous explosive eruption is possible within hours to days.DOST-PHIVOLCS strongly reiterates total evacuation of Taal Volcano Island and areas at high risk to pyroclastic density currents and volcanic tsunami within a 14-kilometer radius from Taal Main Crater. Areas in the general north of Taal Volcano are advised to guard against the effects of heavy and prolonged ashfall. Civil aviation authorities must advise aircraft to avoid the airspace around Taal Volcano as airborne ash and ballistic fragments from the eruption column pose hazards to aircraft. DOST-PHIVOLCS is continually monitoring the eruption and will update all stakeholders of further developments."

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