The earthquake in Hawaii wasn't a volcanic event but rather a tectonic plate movement. There is considerable debate about the exact nature of the Hawaiian island chain and how it relates to the 'plume' effect.
When I saw the data, it looked like it wasn't a volcanic shake.
David Oppenheimer, a seismologist with the US Geological Survey, told KCBS' George Harris that there was was no tsunami because there was no significant displacement of the sea floor."The magnitude of the earthquake was pretty much below the threshold for damaging tsunamis. You typically don't see tsunamis until you get to magnitude 7.0."
Volcano Expert Margaret Mangan said the quake was not set off by volcanic activity.
"It appears that this earthquake is more related to deep structural trigger, rather than a more shallow earthquake that might be attributed to volcanic activity."
The data at the IRIS site showed the series of quakes were pretty deep and at varied levels. When volcanoes cause earthquakes, they tend to be shallow and not affect distant areas. This quake shook most of the island chain which is longer than Texas. To shake such a distance means the earth's plates were moving.
I often wondered about the latest research of anomalies like these. So today is a good time to check out some of the latest scientific research on the web.
Professor Norman H. Sleep, Dept. of Geophysics, Stanford University(see page 11, paragraph 4,5)
the Hawaiian chain is on crack in lithosphere
"A crack propagates through the plate producing volcanism at its tip and causing the lower lithospheric mantle to delaminate on its flanks over a region perpendicular to the track forming the swell. Delamination to produce the swell and the volcanism has tesable implications that distinguish it from plumes....
Plate cracking is evident along the Hawaiian chain. Soloman and Sleep (1974) pointed out the strike of the chain aligns perpendicular to the expected axis of intraplate tension (Stuart et al., this volume). En echelon lineaments of volcanic edifices align along the trends of the numerours chains including Hawaii (e.g., Jackson and Shaw, 1975). These features are compatible with a propagating crack, but also with plumes. Plume-derived melts need cracks to ascend to produce surface hotspots. These cracks preferentially align with the local intraplate stress.
The behavior of the seafloor after the passage of a hotspot provides information on the underlying process. The long-term subsidence of oceanic islands has been known since the time of Darwin....First, ponded plume material produces modest uplifts...a 100-km thick layer with a temperature contrast of 250 K produces 1060 m of uplift.
Hawaii should be added to the list (above) as a ridge-leaving hotspot.
Why is there a 'crack' in the center of the Pacific? The Pacific Plate covers more of earth's surface than any other plate. The runaway train of the Australian plate which is moving faster than any other plate, is relentlessly shoving up and over the Pacific Plate which is shoving northwards towards the North Pole. The mighty Aelutian islands are the firing line of this northwards push. The pressure from the massive Australian Plate must be causing some sort of buckling in the center because the North American continent is shoving towards the Pacific as the Atlantic rift, a much slower process, continues to relentlessly press outwards. In other words, the Atlantic has a long rift running down the center while the Pacific is buckling upwards at the center? Hmmm.
This scientist seems to believe that the chain of islands running west from Hawaii's main island aren't just eroding away but are subsiding, namely, falling lower and lower as the section of lithosphere they are part of experiences less and less pressure from the mantle. This makes on wonder what is pushing upwards on the mantle dead center in the Pacific.
He also talks about Iceland and how it is on a much slower moving plate so it is a much bigger island even though the amount of hot magma flowing upwards is less than Hawaii. Iceland is obviously on a crack, namely the planet-long rift running straight down the Atlantic Ocean which is moving Africa and South America further and further apart.
I suspect Australia's march north is grossly affecting the entire 'Rim of Fire' in the Pacific.
And Australia's climate is changing.
By Kathy Marks in Sydney
Published: 14 October 2006Australia is confronting its worst drought in a century with rampant fires devastating agricultural areas, rivers drying up, crops failing, and farmers forced to sell off their livestock.
The bushfire season has begun months early and the government has pledged financial aid for despairing farmers, already laden with debt after five straight years of drought. Some may earn no income at all this year, and there are fears that the suicide rate in the countryside, which is already high, will soar further.
As this continent moves towards the equator, it will be like some great Sahara. Unlike the many much smaller landmasses, the prevailing winds off the ocean won't turn it into jungle but rather, desert except along the coasts. What sort of havoc this will cause to Asia and India in a few million years is a guess but I would personally say, the prevailing tradewinds will be blocked especially since Australia is provoking a lot of volcanic mountain building.
Just like the Deccan traps caused huge volcanic eruptions as India collided with Asia at the beginning of the Mammalian Age, Australia's crash into Asia will certainly cause major changes in the world's flora and fauna.
Australia is a lovely place and it is sad watching people fall into despair as climatic events overtake hopes for the future. Australia is very much like Texas. This is why both places should be very strongly for controlling global warming. As we saw earlier today with the article about Texas building vast numbers of coal-burning electrical power plants, sanity is in short supply.
Suicide is a stupid solution. I have built many things and lived many places and even when reduced to living in a tent for years and years, even when my husband became too ill to work or help even, I still found a million reasons to live. Sometimes it was just sheer stubborness.
My farm is ideal for sheep. I was driven out of business by Australian sheep which were cheaper than mine. Just like my neighors are shutting down their cattle operations because of cheaper Texan cows, both places abuse the environment stripping it of vegetation even though it is a very fragile place. Overgrazing in order to make a profit leads to climate change. The ground dries up much faster if it is exposed to the hot sun and vegetation that catches the wind, if gone, the wind blows very hard indeed.
The Sahara once was prime grazing and huge herds of animals roamed there and this is where humans learned how to domesticate animals. Now, it is bone dry and virtually uninhabitable.
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