Lava and ash spew from Mt Etna flights redirected

 

Lava and ash spewing out of a crater of the giant Etna volcano in southern Italy forced the closure of nearby Catania airport, ANSA news agency said late Sunday. With a high risk of volcanic ash being blown onto the runways, the airport was closed for safety reasons and flights redirected to nearby Palermo. It is the volcano’s 17th eruptive activity since the start of the year.

http://hisz.rsoe.hu/alertmap/site/?pageid=event_desc&edis_id=VE-20111024-32802-ITA

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Turkey earthquake: Desperate search for survivors

Rescue teams are desperately
searching for people trapped under rubble after a strong earthquake hit Turkey’s
eastern Van region on Sunday.

More than 200 people died and 1,000 were injured in the 7.2 magnitude quake,
many of them in the town of Ercis, where dozens of buildings fell.

Tens of thousands have been sleeping outside in freezing conditions.

The death toll is expected to rise in the coming hours. PM Recep Tayyip
Erdogan has been visiting the area.

Turkey is particularly vulnerable to earthquakes because it sits on major
geological fault lines.

Two earthquakes in 1999 with a magnitude of more than 7 killed almost 20,000
people in densely populated parts of the north-west of the country.

The earthquake struck at 13:41 (10:41 GMT) at a depth of 20km (12.4 miles),
with its epicentre 16km north-east of Van in eastern Turkey, the US Geological Survey said.

It was followed by a series of powerful aftershocks, also centred north of
Van, including two of magnitude 5.6 soon after the quake and one of 6.0 late on
Sunday.

‘Screams for help’

Mr Erdogan has been visiting the affected area by
helicopter.

He said that villages close to Van were the worst affected as most buildings
there were made of clay bricks.

The prime minister thanked other countries for their offers of help but said
Turkey could cope with the disaster on its own.

Up to 80 buildings, including a dormitory, collapsed in the town of Ercis,
about 60km north of Van, while 10 fell in Van itself.

Town mayor Zulfikar Arapoglu appealed for help. “We need urgent aid, we need
medics,” he said.

Ambulances, soldiers and rescue teams rushed to the town, a Reuters
photographer reported from Ercis.

Survivors complained of a lack of heavy machinery to remove chunks of cement
floors that had pancaked on to each other, the Associated Press reports.

Serious damage and casualties were also reported in the district of
Celebibag, near Ercis.

“There are many people under the rubble,” said the local mayor, Veysel
Keser.

“People are in agony, we can hear their screams for help. We need urgent
help.”

The head of Turkey’s seismology institute said hundreds of people could have
been killed.

“We estimate around 1,000 buildings are damaged and our estimate is for
hundreds of lives lost – it could be 500 or 1,000,” said Mustafa Erdik of the
Kandilli Observatory.

Read More: http://www.bbc.co.uk/news/world-europe-15425268

Characteristics and possible evolution of the eruption in El Hierro

On this island, a volcanic eruption occurs fissure and surtseyana type. The volcanic materials could be found taquilitas.

Underwater volcanic eruption continues off the coast of South El Hierro. Eruptive focus closer to the surface of the sea it was located about 150 meters deep. The result of the shallowness on Saturday October 15 began to see the first magmatic material at the sea surface, but stopped a few days after coming to the surface, presumably because the eruptive mouth closed.

The eruption of El Hierro launched at sea pyroclastic

These pyroclastic materials collected by the ships that have come to the point eruption and even coastal areas south of the island rocks are composed of two distinct visually.

Characteristics of the materials recovered from the eruption magmatic

These pyroclasts were formed out of lava 150 meters deep and 2.4 kilometers from the coast El Hierro. On the outside are black and round or oval shaped, but inside is a white, porous material, full of gas bubbles formed by the magma dragged from deeper zones.
The dark material is, according to a preliminary study of non-tip, a taquilita. This type of rock is a volcanic glass formed after rapid cooling of basaltic magma. As for the white material needed more comprehensive analysis.

What kind of volcanic eruption is El Hierro

In addition, the volcanic eruption of El Hierro is fissural type, which means that the lava does go outside along a fracture that can break the surface along a fissure or opening several more or less aligned mouths .

And that is the underwater eruption that takes place on the island of El Hierro appears to have several sources. According to official information would be at least three places that have gone lava and gases.

The lava eruptions of this type of flow with relative ease, ie that are not highly viscous lavas and are not in their composition a high percentage of silica. Basic lavas would.

Surtseyana eruption in El Hierro, the four phases

Also described the surtseyana like rash, by the eruption of Surtsey Island in Iceland. However, in this case the name refers to a volcanic eruption under water near the sea surface and this name affect the eruptive mouths found in shallower waters. The deeper pockets of the underwater eruption does not fall under this denomination.

These eruptions are characterized by four distinct phases. In the first volcanic materials are sea surface as bubbles of lava. Then appear a white column of steam to be followed by explosions caused by the underwater volcano and acquire darker shades. In the fourth stage would form a small island where there would be a fountain of lava that would expand until it ceased to exit.

In the current situation shallower focus of eruptive fissure eruption of El Hierro , which was located about 150 meters deep according to the information given by the PEVOLCA, seems to have closed, although the eruption may continue in deeper areas Building island of El Hierro. However, the volcanic tremor continued on CHIE seismic station that could precisely target the lava is coming out somewhere.

Possible evolution of the volcanic eruption in El Hierro

Thus, the published data on this volcanic phenomenon, although difficult to predict the possible evolution glimpse. The volcanic eruption of El Hierro could be stopped at any time, although in view of the deformation on the island is not expected to be the case in the short term.

It could also continue the rash known foci and in the case of the shallowest, and after passing through the phases of the eruption surtseyana, become an island, but for this last step came to an end would require a large input of magma from below.

If the contribution of magma is higher than the amount of lava that comes out of the different foci or if one of these will be closed for any reason, then it can happen that will open new eruptive mouths, either at sea or on land. If this happened in the sea in shallow areas may be mentioned earlier phases of the eruption surtseyana .

How could last eruption of El Hierro

In any case, the data of deformation and earthquakes in El Hierro which records the IGN, they have not stopped, at least reflect the geological process continues its course, and even may point to the arrival of more magma beneath the island. As for the duration of the volcanic phenomenon , David Calvo, non-tip, aimed at RTVE that could be extended in time but the important thing is the observation and monitoring of underwater eruption near the island to be opened from other sources if any.

Translated by Google. Written by Daniel Martin

http://www.suite101.net/news/caracteristicas-y-posible-evolucion-de-la-erupcion-en-el-hierro-a69990

Deepest and most explosive underwater eruption ever seen happening near Samoa hotspot

Posted on October 20, 2011 by The Extinction Protocol

SAMOA – An underwater volcano bursting with glowing lava bubbles — the deepest active submarine eruption seen to date — is shedding light on how volcanism can impact deep-sea life and reshape the face of the planet. Submarine eruptions account for about three-quarters of all of Earth’s volcanism, but the overlying ocean and the sheer vastness of the seafloor makes detecting and observing them difficult. The only active submarine eruptions that scientists had seen and analyzed until now were at the volcano NW Rota-1, near the island of Guam in the western Pacific. Now researchers have witnessed the deepest active submarine eruption yet. The volcano in question, West Mata, lies near the islands of Fiji in the southwestern Pacific in the Lau Basin. Here, the rate of subduction — the process in which one massive tectonic plate dives under another, typically forming chains of volcanoes — is the highest on Earth, and the region hosts ample signs of recent submarine volcanism. “It was absolutely stunning and exciting, something we’d never seen on the seafloor before,” researcher Joseph Resing, an oceanographer at the University of Washington in Seattle, told OurAmazingPlanet. This submarine eruption is the deepest seen yet, about 2,200 feet (700 m) deeper than NW Rota-1. This was deeper than scientists had expected to see explosive eruptions. Water pressure goes up the further down you go, “so as pressure goes up, the ability of gas as it comes out of magma to cause explosions is diminished, and the thought was that you wouldn’t get explosive eruptions below about 1,000 meters (3,300 feet),” Resing said. Eruptions at centers of ocean floor spreading — where the majority of eruptions on Earth happen — generally seem to occur in relatively short episodes lasting hours to months, but West Mata appears to have erupted near continuously since it was first observed in 2008. This might be because magma is focused there, instead of being spread across many volcanoes at once. “However, this is a question that we don’t currently know the answer to,” Resing said. –OAP

Read more: http://theextinctionprotocol.wordpress.com/2011/10/20/deepest-and-most-explosive-underwater-eruption-ever-seen-happening-near-samoa-hotspot/

Magnitude-7.6 earthquake strikes far off Tonga in South Pacific

NUKU’ALOFA, Tonga — A strong earthquake struck far off the South Pacific island nation of Tonga on Saturday, but there were no immediate reports of damage or injuries.

The U.S. Geological Survey said the magnitude-7.6 quake struck at 5:57 a.m. (1757 GMT Friday), about 541 miles (870 kilometers) south of Nuku’Alofa on Tonga. The quake struck at a depth of 24 miles (39 kilometers).

The Pacific Tsunami Warning Center did not issue a tsunami alert, but its report on the quake said sea level readings indicated that a tsunami was generated.

The quake hit 112 miles (180 kilometers) from New Zealand’s remote, volcanic Kermadec Islands. The remote outpost is generally uninhabited aside from a weather station and a hostel for visiting New Zealand scientists and staff.

New Zealand Civil Defense officials issued but then quickly canceled a tsunami warning.

Another magnitude-7.6 earthquake struck the region in July, but the eight New Zealand staffers at the Raoul Island outpost at the northern end of the Kermadecs were unharmed.

The region lies on the “Ring of Fire” — an arc of earthquake and volcanic zones that stretches around the Pacific Rim. About 90 percent of the world’s quakes occur in the region.

By Associated Press, Saturday, October 22, 2:27 AM

Shiveluch in violent eruption

Shiveluch volcano. © Photo: ru.wikipedia.org/NASA/JSC

Reports speak of a violent volcanic eruption of Mount Shiveluch on Russia’s Far Eastern Kamchatka Peninsula.

Smoke and ash from the volcano have climbed to 10 kilometres, sparking no-fly warnings for the surrounding area. Snow around the crater is rapidly melting, creating mudslides.

Shiveluch supports a caldera of 1.5 kilometres in diameter. Its current activity period started in 1980.

http://english.ruvr.ru/2011/10/16/58828158.html

Red Alert Issued In El Hierro Town As Underwater Volcano Erupts

El Hierro. Google Maps

Spain’s Instituto Geográfico Nacional (IGN) confirmed on Tuesday that an underwater eruption has occurred five kilomtres off the southern coastline of El Hierro, the smallest of the Canary Island. The eruption is Spain’s first since the eruption in 1971 of the Teneguía volcano on the island of La Palma (Canary Islands).

The IGN says all three of its seismic stations on El Hierro in the Canary Islands have registered a volcanic tremor of low frequency in the south of the island at La Restinga, the southern-most village in the Canaries.  The estimated 537 residents of the town were summonsed to a local football field on Tuesday afternoon to be briefed on evacuation procedures.

A Red Alert has since been issued by local authorities for the town. A notice posted on the Emergencia El Hierro website on Tuesday evening stated: “Phase pre-eruptive. It involves the initiation of a preventive evacuation. Make yourself available to the authorities.”

Scientists from IGN and CSIC (Consejo Superior de Investigaciones Científicas), meanwhile, have conducted a reconnaissance flight over the sea to the area south of the island, where they have located dead fish floating on the surface five kilometres from the coast. The dead fish were identified in an area where lower seismic magnitude occurred on October 9, at a depth of approximately 2 km.

The present volcanic activity is understood to be occurring at a depth of 600 metres (just under one kilometre) below sea level, in the Las Calmas sea.

Scientists from IGN, CSIC and the University of Cadiz have established their monitoring base at La Restinga. Efforts are underway to determine if the subsea volcanic vent is widening and if so, in which direction (away or toward El Hierro).

Initial reports of the eruption were received from crews on board four separate ships. Local media agency Canarias7 reported on Monday that Government authorities have suspended ferry activities to and from the 285 square-kilometre island.

English language newspaper  islandconnections.eu reported: “The martime chief for the province of Santa Cruz de Tenerife Antonio Padrón has issued a recomendation that boats should not sail closer than four miles off El Hierro. Divers have also been told to suspend all activities.”

The eruption takes place amidst an unprecedented earthquake swarm in El Hierro. The number of earthquakes recorded since July 17, 2011 on El Hierro has now exceeded 10,000.

Hierro, a shield volcano, has had a single historic eruption from the Volcan de Lomo Negro vent in 1793. The eruption lasted approximately one month and produced lava flows.

The recent surge in the number and intensity of earthquakes prompted officials from the IGN and The Canary Islands Government to raise the alert level for the Hierro volcano to ‘Yellow’ late last month. The alert remained in place on Monday, but the estimated 11,000 residents of El Hierro were being reassured not to be alarmed.

The majority of the earthquake activity shifted from El Golfo in the island’s northwest to beneath the Las Calmas Sea in the south earlier this month. Surface deformations exceeding 35mm have also been recorded on the island in recent weeks.

Evacuations

A dramatic rise in recorded earthquakes on El Hierro prompted officials to evacuate some local residents, shut El Hierro’s main tunnel, and close local schools on 27 September.

The Spanish Civil Guard (Guardia Civil) advised almost 50 residents of the municipality of La Frontera to leave their homes because of landslide fears. Two units of the Spanish military’s emergency intervention unit (EMU) were also placed on standby to depart the nearby island of Tenerife to assist in the possible evacuation of hundreds of other El Hierro residents.

Meanwhile, the island’s main tunnel (Tunel del Golfo), which links Frontera to Valverde, was shut forcing motorists to travel across the 280-sq-km island via a mountain road. The Cabildo de El Hierro also ordered the closure of schools.

Read more: http://www.irishweatheronline.com/news/earth-science/geology/red-alert-issued-in-el-hierro-town-as-underwater-volcano-erupts/41346.html

 

 

Hurricane Jova gathers strength as it moves toward western Mexico

Hurricane Jova was about 260 miles southwest of Manzanillo, Mexico, early Monday, moving at about 8 mph an hour.

Hurricane Jova was about 260 miles southwest of Manzanillo, Mexico, early
Monday, moving at about 8 mph an hour.

Hurricane Jova gathered strength early Monday as it churned
toward western Mexico, sending emergency officials scrambling to open shelter
and coordinate with local governments.

The storm grew to a Category 2 late Sunday, carrying maximum sustained winds
of 100 mph, according to the National Hurricane Center in Miami. It was about
260 miles southwest of the tourist haven on Manzanillo, moving at about 8 mph an
hour, the center said.

Forecasters warned the hurricane would continue to gain strength over the
next two days, making an anticipated landfall by Tuesday evening.

A hurricane watch is in effect from Punta San Telmo north to Cabo Corrientes,
Mexico.

“Our main concern is the welfare of the population,” Trinidad Lopez, civil
protection director in the state of Jalisco, said. “We’re doing everything in
our power to protect people.”

At least 100 shelters were open Sunday for people who could be affected by
the storm, Lopez said. Food, cots and blankets have been distributed, he
said.

Heavy machinery has also been pre-positioned in strategic locations
throughout the state, Lopez said.

Mexico is providing federal assistance, as well. More than 300 soldiers have
been deployed and the Marines in Puerto Vallarta are on alert, Lopez said.

A tropical storm watch also is in effect in an area near Punta San Elmo,
stretching south toward Lazaro Carenas.

Mexico’s National Meteorological Service warned boaters off the country’s
Pacific coast to prepare for increasing rains, waves and winds.

High surf warnings are also in effect, with forecasters warning swells will
strike Mexico’s southwest coast later in the day Monday.

“These swells are likely to cause life-threatening surf and rip current
conditions,” the hurricane center said.

The states of Michoacan, Colima, Jalisco and Nayarit will likely see
significant rainfall, the meteorological service said.

From Rafael Romo, Senior Latin American
Affairs Editor
October 10, 2011 — Updated 0625 GMT (1425 HKT)

Sixteenth paroxysmal eruptive episode from Etna’s New Southeast Crater

20111008_028_730

Ash and steam plume emitted during the paroxysmal phase of the eruptive episode of 8 October 2011 at the New Southeast Crater, seen from Trecastagni (about 15 km southeast of the summit of Etna), at 14:50 GMT (= local time -2). Photo taken by Boris Behncke, INGV-Osservatorio Etneo (Catania)

After little less than 10 days of relative calm, the 16th paroxysmal eruptive episode of this year at the New Southeast Crater (New SEC) of Etna has taken place on the afternoon of 8 October 2011. The culmination of this event, whose observation was very difficult due to bad weather, was rather brief but violently explosive, generating an ash cloud that was blown east-northeast by the wind. Once more, eruptive vents opened both on the southeastern and northern flanks of the New SEC cone.

20111008_Ferrera_400Strombolian activity and emission of lava flows from the eruptive fissure on the southeastern flank of the New Southeast Crater cone, seen from Belvedere, about 900 m southeast of the crater, at 14:14 GMT. Photo taken by Elisabetta Ferrera, University of Catania

20111008_Andronico01_400

The New Southeast Crater after the end of the 8 October 2011 paroxysm, seen from the western rim of the Valle del Bove about 2 km to the south, at 15:35 GMT. Lava is continuing to issue from the fissure on the southeast flank of the cone (at right), whereas a dilute ash plume is being emitted from the crater itself. Photo taken by Daniele Andronico, INGV-Osservatorio Etneo (Catania)

The first clear signs of a reactivation of the New SEC were recorded by the instrumental monitoring network of the INGV-Osservatorio Etneo (Catania) on the morning of 8 October, when there was a rapid augmentation in the volcanic tremor amplitude. This was accompanied by a shift of the tremor source toward the surface, and from its “normal” location beneath the Northeast Crater toward the New SEC. At about 11:00 GMT (= local time -2) the start of eruptive activity was distinctly evident in images recorded by the surveillance cameras as weak and discontinuous Strombolian explosions. Two hours later (13:30 GMT), lava started to overflow from the crater, as usual through the deep notch in its southeastern rim.

At around 13:45 GMT, vigorous Strombolian activity was observed from numerous vents along a short eruptive fissure on the southeast flank of the cone, which had first been active during the  29 August  paroxysm. After 14:15 GMT, weather conditions deteriorated, and the passage from Strombolian activity to sustained lava fountaining and ash emission was not directly observed. However, this passage, around 14:30 GMT, was well audible, and a dense ash and vapor plume rapidly rose above the weather clouds, and then drifted east. At the same time, a lava flow descended the western slope of the Valle del Bove, following the same path as the previous lava flows.

It was probably during this phase that eruptive vents opened on the northeastern flank of the cone, approximately along the fracture that had first opened during the 8 September paroxysm, and two small lava flows were emitted. The more voluminous of these, which issued from the lower end of the fracture, extended downslope for a few hundred meters to invade the central portion of the May 2008 eruptive fissure.

20111008_Zimbone_730

A panoramic view of the Valle del Bove and the New Southeast Crater during the 8 October 2011 paroxysm, seen from the Schiena dell’Asino on the southeast flank of Etna. Photo taken by Antonio Zimbone and published with kind permission of the author

The paroxysmal phase lasted little longer than 20 minutes and ended around 14:50 GMT; ash emission continued until about 17:45, when the volcanic tremor amplitude returned to levels similar to those preceding the paroxysmal episode, and the lava flow fronts appeared to stagnate. The ash cloud was blown east-northeastward by the wind, leading to ash and lapilli falls in a narrow sector that passed from the Ripe della Naca area and the village of Puntalazzo to the town of Mascali.

This paroxysm came little less than 10 days after the previous episode, and it was of shorter duration than any of its predecessors in the series initiated in January 2011 – the culminating phase of sustained lava fountaining and ash emission lasted only about 20 minutes. Another notable feature of this event is the minor eruptive activity on the northeastern flank of the New SEC cone, which occurred along the fracture of 8 September, oriented SSW-NNE in its upslope portion and bending SW-NE in its lower portion. In contrast, the fracture that opened in this area during the 28 September paroxysm lies further to the west, cutting the flank of the “Levantino”, a secondary cone formed in 2000-2001 on the north flank of the old SEC cone. The morphology of the New SEC did not undergo significant changes during this latest paroxysm, though it is likely that the accumulation of new pyroclastic material has led to some further growth in height of the cone.

http://www.ct.ingv.it/index.php?option=com_content&view=article&id=462