Underwater Volcanism

[Turtle]

:) fascinating! :Alien:

 

NOAA - National Oceanic and Atmospheric Administration - Scientists Discover and Image Explosive Deep-Ocean Volcano

 

December 17, 2009

 

Scientists funded by NOAA and the National Science Foundation recorded the deepest erupting volcano yet discovered, describing high-definition video of the undersea eruption as “spectacular.” Eruption of the West Mata volcano, discovered in May, occurred nearly 4,000 feet below the surface of the Pacific Ocean, in an area bounded by Fiji, Tonga and Samoa.

...

For the first time we have been able to examine, up close, the way ocean islands and submarine volcanoes are born,” says Barbara Ransom, program director in NSF’s Division of Ocean Sciences. “The unusual primitive compositions of the West Mata eruption lavas have much to tell us.”

 

The West Mata volcano is producing Boninite lavas, believed to be among the hottest erupting on Earth in modern times, and a type only seen before on extinct volcanoes older than a million years.

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Mission scientists believe 80 percent of eruptive activity on Earth takes place in the ocean, and most volcanoes are in the deep ocean. Until this discovery, NOAA and NSF had sponsored research on submarine volcanoes for 25 years without observing a deep-ocean eruption. Scientists believe further study of active deep-ocean eruptions will provide a better understanding of oceanic cycles of carbon dioxide and sulfur gases, how heat and matter are transferred from the interior of the Earth to its surface, and how life adapts to some of the harshest conditions on Earth.

...

[Turtle]

an underwater volcano near japan is erupting anew today. :rolleyes: :evil: :phones:

 

... According to an announcement by the 3rd Regional Coast Guard Headquarters of the Japan Coast Guard, based in Yokohama, the volcano spewed ash and smoke about 100 meters into the air, and the surrounding sea area changed to a yellowish-green color while other parts became a cloudy gray.

 

According to the Meteorological Agency, the volcano, known as Fukutokuokanoba, has erupted seven times since 1904, when its activities were first recorded. On three occasions, land masses were formed, but all later sank below the waterline. ...

Underwater volcano could create Pacific island

 

video: >> Caught on Tape: Underwater Volcano May Form New Island | WNCT

 

aerial still image: >> http://mdn.mainichi.jp/mdnnews/news/20100204p2a00m0na017000c.html

 

i don't see anything unuusal on the seismogram stations, but i don't usually visit them & so have little to compare them to. :eek: presented for your approval...

seismogram stations for japan: http://www.fnet.bosai.go.jp/freesia/waveform/

[Turtle]

no photos that i can find yet of this new underwater volcanic eruption, but that's par for such a remote course. we'll take what we can get. :phones:

 

Saipan Tribune

...The U.S. Geological Survey's report yesterday stated that an eruption cloud up to 40,000 feet appeared to be over or near Anatahan volcano in the satellite image.

 

USGS said current evidence points to the source being the submarine seamount south of Sarigan.

 

USGS said the cloud may contain ash but could be made up largely of water vapor and appears to be shrinking as northerly winds carry it toward the CNMI and Guam.

 

“No additional volcanic clouds have been detected and it is unknown if submarine activity is continuing. Observers on Sarigan reported hearing a loud explosion from the south, and shortly thereafter receiving ash fall. They also reported the sound of a wave passing by,” USGS said. ...

[Turtle]

news from home...stop we have an unprecedented new view of some undersea volcanoes...stop. see full article & video @ link...go (there is nothing like deep water for a disaster. ;))

Undersea mountains march into the abyss @ bbc

Sonar images of the Tonga Trench. Video courtesy of the Universities of Oxford and Durham and NERC

 

Startling new images from the depths of the Pacific Ocean reveal one of Earth's most violent processes: the destruction of massive underwater mountains. The pictures were created by sonar in waters up to 6km (4mi) deep. They expose how tectonic action is dragging giant volcanoes into a chasm in the seabed.

The volcanoes are strung across several thousand kilometres of ocean floor and are moving westward on the Pacific tectonic plate at up to 6cm per year.The extraordinary scene was captured along the Tonga Trench during a research expedition last summer.The trench is a highly active fault line running north from New Zealand towards Tonga and Samoa.

 

The first images have been released to BBC News as the findings are presented to the annual conference of the American Geophysical Union. They are the result of a joint project by the universities of Oxford and Durham, funded by the Natural Environment Research Council.

...

[7DSUSYstrings]

We start with one eruption, and then build from there. What do we know about underwater volcanoes, and what do we not? ........:eek2: :(

 

Underwater - Submarine Volcanoes

 

 

We are learning more all the time. The question I would have involve the water and steam that finds its way to the lava tubes and magma chambers causing the steam in the first place, regarding how much.

[Turtle]

We are learning more all the time. The question I would have involve the water and steam that finds its way to the lava tubes and magma chambers causing the steam in the first place, regarding how much.

 

thanks for posting. after some searching i could not find any estimates of output rate/volume for even a single "black smoker" as many hydrothermal vents are termed. keep in mind that at the pressures involved there is no steam, rather the water superheats. here's a page you may find of general interest & a few quotes. i'll keep an eye out for some reference to an "amount".

 

Black Smokers

You've probably seen or heard of natural hot springs on land, like Old Faithful at Yellowstone National Park. Similar phenomena occur under the oceans within midocean ridge volcanoes and are called deep-sea hydrothermal (hot water) vents. They are known as black smokers, like the ones seen above. These black smokers are chimneylike structures made up of sulfur-bearing minerals or sulfides that come from beneath Earth's crust. They form when hot (roughly 350¡C)[662 degrees Fahrenheit] , mineral-rich water flows out onto the ocean floor through the volcanic lava on a mid-ocean ridge volcano.

...

Large amounts of heat and chemical mass are transferred from deep within Earth to Earth's surface through deep-sea hydrothermal vents. The chemistry of ocean water is controlled in part by this process. Thus, understanding how deep-sea hydrothermal vents work is critical to understanding the dynamic nature of our planet.

...

[7DSUSYstrings]

thanks for posting. after some searching i could not find any estimates of output rate/volume for even a single "black smoker" as many hydrothermal vents are termed. keep in mind that at the pressures involved there is no steam, rather the water superheats. here's a page you may find of general interest & a few quotes. i'll keep an eye out for some reference to an "amount".

 

Black Smokers

 

 

True at increased pressures boiling temperatures change, thus superheaqting, still, as soon as something disrupts that confined volume, boiling occurs very rapidly and steam does develop, running away with the expansion.

[Turtle]

True at increased pressures boiling temperatures change, thus superheaqting, still, as soon as something disrupts that confined volume, boiling occurs very rapidly and steam does develop, running away with the expansion.

 

you seem to imply that steam is coming out of hydrothermal vents; this is not the case.

 

Hydrothermal Vent

...

Hydrothermal vents in the deep ocean typically form along the Mid-ocean ridges, such as the East Pacific Rise and the Mid-Atlantic Ridge. These are locations where two tectonic plates are diverging and new crust is being formed.

 

The water that issues from seafloor hydrothermal vents consists mostly of sea water drawn into the hydrothermal system close to the volcanic edifice through faults and porous sediments or volcanic strata, plus some magmatic water released by the upwelling magma. In terrestrial hydrothermal systems the majority of water circulated within the fumarole and geyser systems is meteoric water plus ground water that has percolated down into the thermal system from the surface, but it also commonly contains some portion of metamorphic water, magmatic water, and sedimentary formational brine that is released by the magma. The proportion of each varies from location to location.

 

In contrast to the approximately 2 °C ambient water temperature at these depths, water emerges from these vents at temperatures ranging from 60 °C up to as high as 464 °C.[2][3] Due to the high hydrostatic pressure at these depths, water may exist in either its liquid form or as a supercritical fluid at such temperatures. At a pressure of 218 atmospheres, the critical point of (pure) water is 375 °C. At a depth of 3,000 meters, the hydrostatic pressure of sea water is more than 300 atmospheres (as salt water is denser than fresh water). At this depth and pressure, seawater becomes supercritical at a temperature of 407 °C (see image). However the increase in salinity at this depth pushes the water closer to its critical point. Thus, water emerging from the hottest parts of some hydrothermal vents can be a supercritical fluid, possessing physical properties between those of a gas and those of a liquid.[2][3] Besides being superheated, the water is also extremely acidic, often having a pH value as low as 2.8 — approximately that of vinegar. ...

[7DSUSYstrings]

you seem to imply that steam is coming out of hydrothermal vents; this is not the case.

 

Hydrothermal Vent

 

 

Not that steam is issuing from the underwater vents, more as a process of volcanism in general, same as for water at critical pressures. It would be tough indeed for a clearance to develop inside a (super/critically)compressed fluid.

Edited March 24, 2012 by 7DSUSYstrings

[Turtle]

Not that steam is issuing from the underwater vents, more as a process of volcanism in general, same as for water at critical pressures. It would be tough indeed for a clearance to develop inside a (super/critically)compressed fluid.

 

sounds like pseudo-scientific babble to me. :shrug: i do agree there is much yet to learn about underwater volcanism, ergo this thread.

[7DSUSYstrings]

sounds like pseudo-scientific babble to me. :shrug: i do agree there is much yet to learn about underwater volcanism, ergo this thread.

You mean if I say the boiling temperature of water raises proportionally to the containment pressure, that is pseudo-scientific babble or you agree with that part?

[Turtle]

You mean if I say the boiling temperature of water raises proportionally to the containment pressure, that is pseudo-scientific babble or you agree with that part?

 

i agree with that, but i didn't see you say that. having visited your page, it is what you are not saying here that i find questionable. e.g. you say at your page:

The above is the next layer of the mantle as what we know would predict. There are pockets of water and cooler rocks and sand mass that give way to tension areas of steam that lead through the mantle plumes into the hottest spots, where volcanoes may form and expansion develops. ...

 

poor grammar aside, that is pseudo-scientific babble.

Edited March 25, 2012 by Turtle

[7DSUSYstrings]

i agree with that, but i didn't see you say that. having visited your page, it is what you are not saying here that i find questionable. e.g. you say at your page:

 

poor grammar aside, that is pseudo-scientic babble.

 

I've found in general that the ones so quick to assess just about anything as pseudo-science end up revealing themselves to be the worst pseudo-scientifics in the bunch. As a general rule these people are anal retentives and usually cannot follow eccentric creativity, because their imaginations are 2 dimensional, if that. If what you want is someone to wave hands and agree with you, then I'll simply not respond to your posts. I simply don't have time for that GIGO routine.

[Turtle]

I've found in general that the ones so quick to assess just about anything as pseudo-science end up revealing themselves to be the worst pseudo-scientifics in the bunch. As a general rule these people are anal retentives and usually cannot follow eccentric creativity, because their imaginations are 2 dimensional, if that. If what you want is someone to wave hands and agree with you, then I'll simply not respond to your posts. I simply don't have time for that GIGO routine.

 

thanks. i will appreciate no more posts from you. :)

 

moving to the topic at hand.

 

El Hierro Submarine Volcano Eruption

Four months after it began, the underwater volcanic eruption off El Hierro Island persists. This natural-color satellite image, collected on February 10, 2012, shows the site of the eruption, near the fishing village of La Restinga.

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According to El Hierro Digital, measurements of the sea floor by the Instituto Oceanográfico Español found that the volcano’s summit is now only 120 meters (390 feet) beneath the ocean surface—10 meters (30 feet) higher than it was in mid-January. The height of the erupting cone is about 210 meters (690 feet) above the former ocean bottom, with a total volume over 145 million cubic meters (5.12 billion cubic feet) of new material. ...