Posted on 12/23/2006 3:54:50 PM PST by blam
Eruption May Have Been Bigger
Larry O'Hanlon, Discovery News
Dec. 21, 2006 — One of the largest volcanic eruptions on record just got bigger.
The Taupo Volcanic Zone of New Zealand appears to have had twin eruptions only 20 miles apart within days of each other a quarter-million years ago. Each eruption belched out more than 25 cubic miles (100 cubic kilometers) of rock and volcanic ash.
This is the first evidence of twin supervolcanic eruptions.
"It's possible one of these triggered the other," said geologist Darren Gravley of the University of Auckland, New Zealand. But exactly how the triggering might have worked is uncertain.
What is clear from the explorations of Gravley and his colleagues of the Mamaku and Ohakuri volcanic deposits is that they were created very close in time. That's surprising, since most caldera or "supervolcano" eruptions in any one region tend to be tens of thousands of years apart, or at least that's been the general idea until now.
Among the signs that the rocks from the two eruptions were piled on one another is the conspicuous lack of erosion on the first volcanic deposits — which is striking, considering the rainy climate.
Previous studies that looked only at the radioisotope dates of the volcanic rocks from the eruptions missed the timing details, Gravley said, because they have a margin of error of 10,000 years — way too low a resolution.
"You’ve got to look at the physical evidence," said Gravley. "It's really getting into the nitty-gritty. From the stratigraphy (rock layers) it’s clear two were erupting at the same time. That just blows away any (regional frequency) studies out of the water."
Gravely and his colleagues have published their double eruption discovery in the latest issue of the Bulletin of the Geological Society of America.
The bad news is that double eruption represents a whole new way that supervolcanoes can threaten humanity.
"This is of course a major issue to consider for volcanic risk," said caldera researcher Gerardo Aguirre-Díaz of the Universidad Nacional Autónoma de Mexico in Juriquilla, Mexico.
Caldera eruptions are far less frequent than other volcanoes, but when they do erupt, "the consequences for the surroundings and in general for the world would be enormous, because these explosive eruptions are many orders of magnitude bigger than a more common eruption from a volcano, such as Mount St. Helens or Vesuvius."
I didn't like the part where they revealed that the destruction of only six points would 'down' the electrical power of the entire US.
I would think she'd fall about two feet, at which time her butt will stop her.
And plug the leak too.
< }B^)
That is, of course, unless the crack propagates.
'sok I have it on good authority that it simply can't be done.
Which crack? Will she do the splitz?
I had a twin eruption this morning.
bump4later
It might be interesting to see if we could figure out a way to release the thermal energy in a controlled and useful manner. It might even make us energy-independent from the Saudis
Oh God, we're all gonna DIE!!!
Nope! The Chinese would figure a way to extract the energy, solve mankind's energy problems for the next five thousand years and sell us back the energy from our own caldera. Why shouldn't they sell us energy? All our other enemies do!
Are you series???
Impossible? Why?Once again the mind of the average layman thinks that things are stale, stagnant and unable to 'adapt' to the circumstances presented; components of a system (call it 'the grid' in laymans's terms if you wish) today are "islanded", disconnected inadvance/PRIOR to the expected influence of an incoming geomagnetic storm.Solar storms can damage electrical systems. Do it on large enough scale, and from a practical POV, the manufacturing capacity to replace all that stuff just isn't there any more.
This prevents the SLOW moving magnetic field changes from inducing DC currents in lines that in turn cause transformer "BH" curve shift, a shift that can cause a transformer to "saturate" on a portion of the incoming AC waveform and is the main source of potential (note I said potential) damage; smaller 'islanded' systems are not affected the same way a long tie-line is between distant points (longer run, more induced current).
Excerpted from: https://www.npcc.org/publicFiles/documents/seasonalNew/NPCC_Reliability_Assessment_for_Summer_2004.pdf
Geomagnetically Induced Currents (GICs)Past experiences have shown the serious effect that geomagnetic disturbances can have on the NPCC bulk power system.
Quasi-DC currents induced in power lines flow to ground through transformer neutral connections. This can result in saturation of the transformer core leading to a variety of problems, including increased heating that has resulted in transformer failures. In addition, the harmonics generated in the transformer, as a result of the saturation, may produce unanticipated relay operations, such as sudden tripping of transmission lines or shunt capacitors.
GICs are produced by the magnetic field variations that occur when a mass of electrically charged particles from a solar coronal mass ejection impacts the earth?s magnetic field. Because of the low frequency compared to the AC frequency, the geomagnetically induced currents appear to a transformer as a slowly varying DC current.
GIC flowing through the transformer winding produces extra magnetization, during the half-cycles when the AC magnetization is in the same direction this effect can saturate the core of the transformer. This also results in severe distortion of the AC waveform with increased harmonic levels that can cause incorrect operation of relays and other equipment on the system and may lead to problems ranging from trip-outs of individual lines, transformers or shunt capacitors to collapse of the whole system.
GIC activity correlates to 11-year sunspot cycles. We are presently in Cycle 23, which began in 1996 and is predicted to end about January 2007. During the portion of the solar cycle that has greater sunspot activity, there is a higher probability of GICs occurring, which could impact the NPCC system.
Observations of sunspot activity only provide insights as to the timing of the release of energy; it is the solar winds that ultimately determine the intensity and duration of a geomagnetic storm and those areas of the earth that will be ultimately affected. A satellite positioned between the earth and the sun is capable of determining the intensity of the storm. The timing between when this satellite senses the magnitude of the storm and when the effects are noted on the earth is less than 1 hour.
Aye!
And it's Armageddon Week on the History Channel.
AHHHHHH!!!!
Well, you can just ROCK me to sleep tonight!
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