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

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

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

The Extinction Protocol

October 8, 2011 ALASKALava has reached the edge of a crater in a volcano in Alaska’s remote Aleutian Islands, indicating the mountain could explode and send up an ash cloud that could threaten aircraft. The Alaska Volcano Observatory says satellite images show lava at the edge of the crater rim of 5,675-foot Cleveland Mountain on uninhabited on Chuginadak Island, about 940 miles southwest of Anchorage. Volcano monitors say if the dome continues to grow, it could overflow the rim and increase the possibility of an explosion. The observatory says an eruption could send up an ash cloud 20,000 feet or more. The nearest village, Nikolski, is on another island about 50 miles east and has 18 permanent residents. The village was not considered in harm’s way in previous eruptions of the volcano. –ABC News

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Earthquakes at El Hierro almost at 10,000 and Magma moving upwards

Friday, 07 October, 2011 at 17:12 UTC

The number of earthquakes recorded since July 17 , 2011 on El Hierro, the smallest of The Canary Islands, has almost reached 10,000, the Instituto Geografico Nacional (IGN) reported on Friday. The IGN also confirmed surface deformations exceeding 35mm on the 280-sqkm island, where residents have been put on alert for a possible volcanic eruption. The agency confirmed on Friday that 858 earthquakes, most of them located in the sea to the SW of the island, have been recorded in the 7 days since 30 September, 2011. During this period, 60 earthquakes were felt by the island’s estimated 10,000 residents. The strongest of the tremors measured 3.8 magnitude on the Richter Scale. Since 17 July, 9639 earthquakes with epicentres both North and South of the NW Ridge and depths between 10 and 15 km have been recorded. 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 Friday. Seismologists say the majority of the earthquake activity has shifted from El Golfo in the island’s northwest to beneath the Las Calmas Sea in the south.

However, magma is now on the move upwards while the depth of earthquakes has become increasingly shallow in recent days with most being recorded at a depth of 9 to 14 kilometres. Movement of magma towards the surface signifies that a volcanic eruption is likely to happen, but the timing of such remains unclear. Volcanologist Juan Carlos Carracedo last week suggested that an eruption on El Hierro would “not be a major surprise”. He explained: “It is the youngest of the Canary Islands. There is a ball of magma which is rising to the surface and it is stationed at the limit of the earth’s crust. At the moment we do not know if that ball of magna will break the crust and cause an eruption.” IGN Director, María José Blanco said that any eruption on El Hierro would most likely have a “low explosion value”. A dramatic rise in recorded earthquakes on El Hierro last week prompted officials to evacuate some local residents, shut El Hierro’s main tunnel, and close local schools. 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.

El Hierro is situated in the most southwestern extreme of the Canaries. The island was formed after three successive eruptions, and consequent accumulations, the island emerged from the ocean as an imposing triangular pyramid crowned by a volcano more than 2,000 metres high. The volcanic activity, principally at the convergence of the three ridges, resulted in the continual expansion of the island. A mere 50,000 years ago, as a result of seismic tremors which produced massive landslides, a giant piece of the island cracked off, crashed down into the ocean and scattered along the seabed. This landslide of more than 300km3 gave rise to the impressive amphitheatre of the El Golfo valley and at the same time caused a tsunami that most likely rose over 100 metres high and probably reached as far as the American coast. According to ElHierro.com: “Although over 200 years have elapsed since the last eruption, El Hierro has the largest number of volcanoes in the Canaries with over 500 open sky cones, another 300 covered by the most recent outflows, and some 70 caves and volcanic galleries, notably the Don Justo cave whose collection of channels surpasses 6km in length.” El Hierro is located south of Isla de la Palma (population 86,000), currently the most volcanically active of the Canary Islands. About a half a million years ago, the volcano, Taburiente, collapsed with a giant landslide, forming the Caldera de Taburiente. Since the Spanish occupation, there have been seven eruptions.

http://hisz.rsoe.hu/alertmap/site/?pageid=event_update_read&edis_id=EQ-20110824-32077-SPI&uid=11509