Volcanoes
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Bizarro Earth

Campi Flegrei supervolcano raising anxiety among Italian residents

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A restive supervolcano west of Naples is raising nervousness in the local Italian population. The ground of the Campi Flegrei "burning fields," also known as the Phlegraean Fields, has risen more in recent weeks than it has in a long time. This does not necessary indicate a heightened risk of an eruption, however, said Thomas Wiersberg, a scientific drilling expert for the German Research Centre for Geosciences (GFZ) in Potsdam. The Phlegraean Fields are a large caldera, or volcanic crater, lying mostly underwater off the Italian coast. The caldera is thought to have been formed by a massive eruption some 35,000 to 40,000 years ago. The last major eruption in the fields of boiling mud and sulphurous steam holes, one of a few dozen super volcanoes worldwide, occurred in 1538.

Wiersberg is part of an international research team that began drilling into the ground not far from the caldera last summer to monitor possible early warning signs of an eruption. The team has drilled a pilot hole to a depth of 500 meters but no data has been gathered yet, Wiersberg said in an interview with dpa. Italy's Department of Civil Protection recently raised the alert level for the Phlegraean Fields, where Wiersberg said the ground was rising by about three centimeters a month. There are concerns that a magma chamber under the fields, presumably connected to the one under Mount Vesuvius, east of Naples, is filling up, the rising pressure possibly heightening the danger of an eruption.

Bizarro Earth

Indonesia's Mount Lokon volcano shaken by double eruptions

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Mount Lokon in Tomohon, North Sulawesi, erupted twice throughout Thursday (31/01/2013) afternoon. Head Volcano Observation Post Lokon and Mahawu, Center for Volcanology and Geological Hazard Mitigation (PVMBG) Bandung Geological Agency, Ruskanda Farid Bina, said the first explosion occurred at 6:54 pm and was followed by a second explosion at 10:44 pm, and that was followed by a boom that sounded up to the settlements located around the crater.

"We could not observe the height of the eruption of dust because of the condition of the fog around the crater. At first eruption eruption dust altitude of about eight hundred yards," said Farid. He said the series of eruptions occurred after an increase in seismicity that occurred on Wednesday (30/1) at 22:54 pm. "Until now the status is still at alert level three," he said. - Inilah translated

Bizarro Earth

Russian scientists voice concerns about dangers of a supervolcano erupting in Italy

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It looks like we may be in for an earth-shattering explosion. A dormant super volcano appears to be stirring under the Phlegraen Fields of Naples in Italy. Rising soil temperatures and surface deformation in the area have alarmed seismologists. In the distant past, volcanic super eruptions caused global climate change responsible for mass extinctions of plant and animal species. So far, scientists are unable to model the potential consequences of an awakening supervolcano. Latest studies show that the Phlegraen Fields have actually been swelling above sea level at a rate of 3 cm per month. Micro quakes and large amounts of gases accumulated in soil indicate that the volcano may be preparing to erupt, says Vladimir Kiryanov, Assistant Professor of Geology at the St. Petersburg University.

"The Phlegraen Fields is a supervolcano. Yellowstone in the United States and Toba in Indonesia are also supervolcanoes capable of spewing more than 1,000 cubic km of magma. These are catastrophic eruptions. There was a huge volcanic eruption in the Phlegraen Fields some 30,000-40,000 years ago. Volcanic ash from that eruption is still found in the Mediterranean, Bulgaria, Ukraine, and even in Russia. We are now seeing the expansion of a magma pocket, which means that there might be an eruption at a certain time."

Bizarro Earth

Eruption of Japan's Mt. Fuji volcano could force the evacuation of more than half a million

An eruption of Mount Fuji could force some 567,000 people to evacuate their homes, according to a new estimate. The projection is part of an evacuation plan crafted by the Shizuoka Prefectural Government that also says more than 130,000 people, comprising some 50,000 households, would have to relocate if lava were to reach residential districts in the city of Fuji, which lies just south of the 3,776-meter mountain. Depending on the number and locations of vents, evacuation from wider areas could be needed. The plan is based on a hazard map prepared by the central government based on Fuji's last eruption, in 1707. Under the evacuation plan, 10 zones have been designated at the foot of the mountain based on the expected direction of lava flows. The plan specifies evacuation zones in four grades.
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The Yamanashi Prefectural Government is preparing a similar evacuation plan. Plans will be finalized at a consultation forum involving Shizuoka, Yamanashi and Kanagawa prefectures and the central government. Joint evacuation drills in the three prefectures will also be conducted. - Japan Times

Bizarro Earth

Crater lake on White Island volcano, New Zealand dries up, as activity increases

The hot crater lake on White Island has now completely dried up as explosive rocks, mud and gas continue to be thrown into the air from the active volcano. White Island has been spewing a steady stream of gas since activity heated up in December. It's the most active the volcano has been since 2000. GNS Science vulcanologist Brad Scott said a "small tuff cone" was forming on the bottom of the crater lake, and the active vent was producing "vigorous bursts" of mud, rock, steam and gas up to 100 meters into the air. "GNS Science's past monitoring of the island shows that new eruptive episodes often develop out of this type of activity," Scott said.
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"Small muddy lakes sometimes form in craters. As the unrest develops, geysering and explosions occur through these lakes, becoming more vigorous with time." He said the activity did not necessarily mean an explosion or full-scale eruption would happen, although one could at any time. Even though there was an elevated risk to tourists on the island, conditions weren't so dangerous that people could not travel there. Tourism has, in fact, been booming at White Island as the volcano heats up, with visitors eager to see some explosive action. Frontier Helicopters is one of three helicopter tour operators which fly around the island.

Blue Planet

Tangaroan, new type of volcanic eruption

New type of volcanic eruption
© National Oceanography Center & National Institute of Water and Atmospheric ResearchMacauley volcano
An international team of researchers from the UK and New Zealand has discovered a previously undocumented type of eruption in underwater volcanoes.

Volcanic eruptions are commonly categorized as either explosive or effusive.

Inside volcanoes, gases are dissolved in the molten magma as a function of the very high pressures and chemistry of the magma. In the same way that gases dissolved in carbonated drinks bubble up when you take the lid off, when magma is erupted as lava, the pressure is relieved and the gases exsolve to form small gas bubbles or so-called 'vesicles.'

In explosive eruptions these vesicles expand so quickly they fragment the magma, violently ejecting lava, which cools and degasses to form solidified pumice that can be sufficiently light to float on water.

In air pumice is obviously associated with violent, explosive eruptions. Consequently underwater volcanoes flanked by highly vesicular pumice have, to date, also been interpreted as having erupted explosively.

Bizarro Earth

10 volcanic earthquakes rattle Philippines's Taal Volcano: Activity increases in the last 24 hours

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The Philippine Institute of Volcanology and Seismology said Tuesday the seismic activity of Taal Volcano in Batangas province has increased in the past 24 hours. Phivolcs Director Renato Solidum, Jr. said the agency has recorded 10 volcanic quakes from 7 a.m. Monday to 7 a.m. Tuesday. But Solidum said no steaming has been observed in the past 24 hours and water temperature at the main crater lake decreased from 31.7 to 30.9 degrees Celsius.

The Phivolcs chief noted the volcano's Alert Level 1 will be maintained as "10 volcanic quakes are still appropriate for a volcano that is under abnormal level." He said that a volcano under Alert Level 1 means that abnormal volcanic activities are observed, though a hazardous eruption is not imminent. Since January 18, Solidum said Taal Volcano was relatively calm, with its seismic network recording "zero to eight" volcanic earthquakes in a day. - MST

Bizarro Earth

Eruptive activity on the rise at two sites on Big Island's Kilauea volcano

Eruptive activity at the Big Island's Kilauea volcano is picking up at the Pu u Oo vent and Halemaumau Crater. At the Pu u Oo vent, situated in the volcano's East Rift Zone, lava flows are sporadically spilling onto the east flank of the vent. The volume of lava streaming to ocean entry is increasing slightly, with small entry points now spread along the coastline near Kupapu Point on both sides of Hawaii Volcanoes National Park. The current ocean-entry flow has been under way since mid-November. This month marks the 30th anniversary of Kilauea volcano's ongoing East Rift Zone eruption. During its first three years, spectacular lava fountains spewed from the Pu u Oo vent.
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Since then, nearly continuous flow has built a vast plain of slow-moving pahoe hoe lava stretching from the volcano's rift zone to the Big Island's shoreline. Also, in recent months, at Kilauea volcano's summit caldera, the lava lake swirling in Halemaumau Crater has been rising to record levels. Since March 19, 2008, when an explosive eruption formed the lava lake, its surface level has remained mostly below the inner ledge (about 100 feet below the floor of Halemaumau Crater).

Bizarro Earth

Puyehue-Cordon Caulle volcano erupts in Chile

A new (so far small) eruption began yesterday from Caulle volcano, local sources reported. Ash emissions reaching 11,000 ft (3.4 km) altitude were reported by Buenos Aires VAAC. Local news report ash fall over Puyehué, Entre Lagos and Osorno today. - Volcano Discovery
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Bizarro Earth

Tavurvur volcano erupts in Papua New Guinea, ash cloud diverts flights

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Eruptions of Papua New Guinea's Mt Tavurvur have forced some flights in and out of New Britain to be cancelled. The ash and vapor blowing from the volcano affected flights to Tokua Airport. Air Niugini says the flight suspension came into effect on Monday and will continue for an indefinite period. Newspaper reports say low to loud roaring and rumbling noises were heard on Sunday night when the volcano erupted. Tavurvur is an active volcano that lies near Rabaul in Papua New Guinea. It is a sub-vent of the Rabaul caldera and lies on the eastern rim of the larger feature. The volcano is most well known for its devastating eruptions over Rabaul. Mt Tavurvur is the most well known volcano in Rabaul caldera, and has erupted as recently as January 2009. The last time the volcano erupted was in 2011. - Radio New Zealand Wikipedia