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

Advertisements

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

Malaysia and 19 other nations to join Tsunami alert test

Published: Friday October 7, 2011 MYT 9:24:00 AM

LONDON: Almost seven years after the devastating tsunami of 2004, over 20 nations including Malaysia will participate in a full-scale exercise to test the operational capacity of the Indian Ocean tsunami alert system on October 12, Press Trust of India (PTI) reported.

The Exercise ‘IOWAVE 11’ will re-enact the seismic events of December 26, 2004, simulating a 9.2-magnitude quake that occurs northwest coast of Sumatra, Indonesia, sending waves across the Indian Ocean that strike the coast of South Africa 12 hours later.

The test will also include the evacuation of coastal communities in several countries, notably India and Malaysia.

UNESCO Director-General Irina Bokova will mark the transition of responsibility for the tsunami warning system with a video address to the authorities of the three countries on the same date.

The exercise aims to evaluate the system’s operational capacity, the efficiency of communications among the different actors, and the state of preparation of national emergency services.

The re-enactment of the seismic events will test the Indian Ocean Tsunami Warning and Mitigation System (IOTWS), Press Trust of India (PTI) quoted the UN’s Educational, Scientific and Cultural Organisation (UNESCO) as saying in a press release.

Bulletins will be issued by the new Regional Tsunami Service Providers (RTSPs) in Australia, India and Indonesia, it said.

This exercise, organised under the auspices of UNESCO’s Intergovernmental Oceanographic Commission, will also see responsibility for the issue of advisories handed over to the countries of the region through a new regional tsunami advisory service.

The Indian Ocean nations decided to establish an Indian Ocean Tsunami Warning and Mitigation System in the wake of the 2004 catastrophe.

They requested that UNESCO’s Intergovernmental Oceanographic Commission establish an Intergovernmental Coordination Group to provide a governance mechanism for the new system, which became partially operational in 2005, the UNESCO said.

Since then, the Japan Meteorological Agency and Pacific Tsunami Warning Centre have issued bulletins to 28 Indian Ocean nations.

They will continue to provide this service until the end of 2012, at which time an evaluation of the new regional advisory service will be carried out.

So far, Australia, Bangladesh, Comoros, France (La Reunion), India, Indonesia, Iran, Kenya, Madagascar, Malaysia, Maldives, Mauritius, Mozambique, Myanmar, Oman, Pakistan, Seychelles, Singapore, Sri Lanka, Tanzania, Thailand, Timor Leste, Yemen have signed up for the October 12 test, the UNESCO said.

The 9.2-magnitude earthquake and subsequent tsunamis along the coasts of most landmasses bordering the Indian Ocean, killed over 230,000 people in 14 countries.

It was one of the deadliest natural disasters in recorded history. Indonesia was the hardest hit, followed by Sri Lanka, India, and Thailand. Bernama

http://thestar.com.my/news/story.asp?file=%2F2011%2F10%2F7%2Fnation%2F20111007093729&sec=nation

Project Flood Nuclear Warnings: 10,000 evacuees prep, 60 buses standby

Across river from the state of Nebraska’s Fort Calhoun Nuclear plant, possibly leaking radiation now, Red Cross is preparing for 10,000 evacuees as a Warning Level 1 has been issued in Project Flood 2011 where the Mighty Missouri River continues swelling, and water is bubbling from the ground near the levee. Tornado sirens are planned to get people out of harms way while over sixty buses standby to haul people if evacuation is mandated.

The Warning includes, “LEVEE MAY BE IMPACTED. MAKE PREPARATIONS TO LEAVE.” Families are packing in Council Bluffs, Omaha, Nebraska after water is forcing sand into their homes according to Action3News.

Although the Omaha based news station made no mention of the nearby nuclear power plant facing catastrophe, Omaha Public Power District (OPPD) that owns the nuclear facility has. On its website, OPPD warned people to not be in the floodwaters due to possible radiation leaking from the nearby nuclear power plant.

Earlier on Saturday, the Russian Federal Atomic Energy Agency (FAAE) released information provided to them by the International Atomic Energy Agency (IAEA) stating that the Obama administration ordered a “total and complete” news blackout relating to any information regarding a near catastrophic meltdown of Fort Calhoun Nuclear Power Plant.

Weather Underground reports an “Active Advisory: Flood Warning (US Severe Weather) is in effect for the area.

Officials report that if a levee is failing, a Level 2 Warning will be issued.

Evacuation is mandatory if a Level 3 Warning is issued. Tornado sirens will sound if a Level 3 is in effect. City officials advise that if a Level 3 is issue, “Please report to the processing Center located at Iowa Western Community College (unless a different site is advised).”

In the case of a Level 3 Warning, the official advisement is that the “primary evacuation route is (to be announced) and you secondary evacuation route is (to be announced).”

“If you are unable to leave on your own, call 328-4672. Do not call 911 unless it is an emergency.”

City officials are advising people to register for a Code Red.

“Fire Chief Alan Byers says he can’t tell at this point how bad it will get or how many people will be affected,” reports Action 3 News.

Continue reading on Examiner.com Project Flood Nuclear Warnings: 10,000 evacuees prep, 60 buses standby (vid) – National Human Rights | Examiner.com http://www.examiner.com/human-rights-in-national/project-flood-nuclear-warnings-10-000-evacuees-prep-60-buses-standby-vid#ixzz1Pj5JsAoy

Planning for Peace of Mind

Check out these two great emergency planning lists packed full of important information, including many things you might not think of. Print them out for your family prepping now and get started. The peace of mind just having some preparing done is priceless, and you may just be thankful one day that you did it!

familydisasterplan-sdc This Family Disaster Plan and Personal Survival Guide is from the San Diego County Office of Emergency Services.

familydisastercalendar The Family Disaster Supplies & Preparedness Calendar is intended to help you take appropriate preparedness actions and create a 3–7 day disaster supply kit before the next emergency happens. Using the calendar, your family can assemble an emergency kit in small steps over a six month period.

Cascadia Subduction Zone

Found an interesting article on the above:

Safe in the Sound?

That obligatory article that’s going to scare the bejesus out of you about the possibility of an earthquake in the South Sound

By Nikki Talotta on April 20, 2011

Do you know, according to the Pacific Northwest Seismic Network, there have been more than 35 earthquakes in Washington state just in the last two weeks?

Do you know we live near one of the most hazardous faults in the world?

Do you know this particular fault line – the Cascadia Subduction Zone – is aching to release a megathrust earthquake?

Now, imagine this fault ruptures and a 9.0 magnitude earthquake violently shakes the Pacific Northwest.

“It would be like a freakishly monstrous catapult that hurls 75,000 square miles of rock, the margin of a continent, as much as 65 feet,” says Patrick Pringle, associate professor of Earth Sciences at Centralia College, national author and overall geo-enthusiast.

In Olympia, the Capitol building would sway, shake and essentially sink into the soft ground that holds the Capitol campus. The quaking would last three minutes or longer, perhaps the scariest three minutes of a lifetime. In the aftermath there would be struggle to contact friends and family. Transportation and technical communications would come to a halt.

In Tacoma, homes would be knocked into the Narrows by earthquake induced landslides; the ground would liquefy near the Tacoma flatlands, and historical buildings would crack, strain and crumble.

In the wake of Japan’s devastating earthquakes, this scenario is not difficult to imagine.

“The Cascadia Subduction Zone is almost a mirror image of the one in Japan,” says Pringle.

A subduction zone, where oceanic plates collide with colossal continental plates, essentially slipping a new slab of crust under an old one, puts tremendous strain on the Earth’s surface between quakes, explains Pringle.

Running from Vancouver Island to Northern California, the Cascadia Subduction Zone is 700 miles long.

You can follow the trail of volcanoes through the Pacific Northwest to get an idea of where these plates collide. (Glacier Peak and Mounts Baker, Rainier, St. Helens, Hood, etc.) This chain of volcanoes, which Pringle refers to as “sleeping giants,” due to their mild – but possibly explosive –  nature, are part of the Ring of Fire, a spread of more than 450 volcanoes along coastal waters which include Japan, Indonesia, Russia, Chile and other geographically unstable parts of the world.

The Northwest is no stranger to the Earth’s power. The Mount St. Helens  eruption, mudslides, lahars, fires and floods have all scarred our landscape, forever changing history.

Most notable, perhaps, is the megathrust earthquake that shook the West Coast in the year 1700. Although there was no formal recordkeeping in the region then, oral legends from local tribes describe tragic experiences caused by the great tectonic disturbance. Evidence from carbon dating, sediment left by tsunamis and studies of tree rings, all point to a grim past. In Japan, there is even documentation on rice paper of the country experiencing tsunami waves likely resulting from a massive earthquake in the Cascadia Subduction Zone during the same time.

The fact that the Pacific Northwest is ripe for ruin is not breaking news. The Earth’s timeline places a major earthquake in this region every 250 to 1000 years, with an average of one every 500 years.

The last megathrust was over 300 years ago. Basic math shows us the odds are not in our favor.

Since science is not fiction, when we experience the “big one,” results will be catastrophic.

With the possibility of thousands dead or missing, people will be a main concern. But post-quake financial realities would soon hit as well, like months of clean up and repair, and billions of dollars in damages. The Nisqually earthquake in 2001 (magnitude 6.8) caused almost $2 billion in damages; imagine the damage a 9.0 mega thrust would cause. The agency EQE International, which specializes in risk management, estimates more than $800 billion in damages.

Forget post-quake costs; with an already tight state budget, will we have the means to realistically finance preventive education programs, pay to seismically retrofit structures for safety (have you seen all the old bridges over Interstate 5?) and adequately fund scientists and engineers?

Patrick Pringle tells me that while he was working for the state Division of Geology the budget was cut by nearly 42 percent during the 2003-05 fiscal years.

“They cut the entire geological hazard section except for one researcher,” he recalls.

“I’m afraid of seeing the baby get thrown out with the bathwater once again,” Pringle says of the dwindling state funds, “because many of the state scientists have had to rely on grants to do their important work.”

Part of the problem is it often takes a major disaster to stir up concern, a shake and wake, if you will.

“A lot of us tend to forget about earthquakes, the last one here was 10 years ago,” says Tacoma Community Relations Manager Rob McNair-Huff, who, together with his wife Natalie, wrote Washington Disasters: True Stories of Tragedy and Survival, highlighting 22 natural disasters that have rocked this region.

The husband and wife team recently presented their book at the Tacoma Art Museum, with an afterparty of earthquake preparedness tips and kits.

It’s important that these types of gatherings, education and resources are available to the community.

“With a small budget, we need to use tools like social media; accounts on Facebook and Twitter,” says McNair-Huff. “And in the event of an emergency, we can use these for real-time outreach.”

In the opinion of this bartender/writer, you might even make it a little fun –  host an earthquake/disaster preparedness party and serve drinks like martinis (shaken, not stirred), Rainiers and mudslides. And for a non-alcoholic alternative try earthquake milkshakes with chunks of rocky road.

And then talk. Talk about evacuation routes and designate meeting places. Talk about resources. Talk about survival techniques. Talk about basic first aid. And talk about how to educate even more.

Because, we can never be too sure.

“You just wait,” assures Pringle, “there is a chance we’re going to experience a major earthquake in the next few decades.”

http://www.weeklyvolcano.com/mudroom/special-report/2011/04/imagine-Cascadia-Subduction-Zone-ruptures-9-magnitude-earthquake-violently-shakes-Pacific-Northwest/