Skip to comments.Deep structure imaged under Hawaii
Posted on 12/03/2009 7:25:30 PM PST by neverdem
Seismic experiment gives best evidence yet for mantle plumes.
Geologists have obtained the best image yet of a plume of hot rock that rises from Earth's deep mantle and fuels the volcanoes of the Hawaiian islands.
The study, led by geophysicist Cecily Wolfe at the University of Hawaii at Manoa in Honolulu, reveals the structure of the plume down to at least 1,500 kilometres. Critics have questioned in recent years whether such plumes even exist.
"This is a spectacular experiment that succeeded in getting data for putting the plume theory to the test," says Wolfe. The results are published this week in Science1.
The plume hypothesis, first proposed by geophysicist Jason Morgan in 1971, provides an explanation for the volcanic hotspots in Hawaii, Yellowstone and other regions that lie at the centres of tectonic plates. Theoretical models and studies of Earth's temperature and chemistry over the past 30 years seemed to support the idea, but direct measurements of the deep mantle remained out of reach.
So in 1999, Wolfe and her colleagues began to plan a US$4.5-million seismic experiment called the Plume-Lithosphere Undersea Melt Experiment (PLUME) to measure the velocity of earthquake waves using ocean-bottom sensors around Hawaii. Because waves move more slowly in hotter materials, researchers could use the data to visualize the structure of the plume. In 2005, the team tossed 36 seismometers off the side of a ship for their first one-year deployment. The following year they deployed a broader array...
(Excerpt) Read more at nature.com ...
Scientific consensus has determined that plumes of this nature have no measurable effect on ocean temperatures. /s
I guess back in igneous petrology, we were taught that these were called “hotspots.” The Hawaiian Islands have been formed as they moved across it to form the volcanoes that form the chains.
It isn’t until after they erupt and spew massive amounts of CO2, other gases and particulate debris, such as ash, high up into the atmosphere, that they affect the world’s global temperature.
Ice age, anyone?
Hmmmm..Phil Jones and his cabal should take notice of how science is supposed to work.
I’d love to see an illustration of this effect.
That should be interesting, one plume under the sea bed and one under the crust.
Don’t get too excited about this. It could be a complete fabrication, with falsified data and all. Remember this is from Nature. Didn’t they recently come out defending the UEA Climate Frauds, and claiming they did nothing wrong?
Birds of a feather...
Remember this is from Nature News citing an article in Science. Does Climategate mean no science or science reporting is credible anymore? Do you want to reject all science? You don't have to compound the damage that Climategate caused. Real scientists keep an open mind, but maintain a certain scepticism about anything claimed to be new. Just because Climategate is a disaster for climatology and some reporting doesn't mean that the rest of science and science reporting is corrupted.
FReepmail me if you want on or off my health and science ping list.
The Hawaiian hot spot was said to erupt through the surface. If the surface moved, new islands formed.
Now then. Are not the hot spots the result of the plumes? Are not the hotspots the current surface location of the plume?
You got me. It is all theoretical. Mathematical models and such. Like trying to tell me what elements are present on the Planet Vultron in the Andromeda Galaxy from a telescope.
How do we know the difference between "science", "political lies" or grant pumping?
And is GE the new tobacco executives telling us "it doesn't cause cancer"... I'd trust Bernie Madoff more...
Well, Algore's science works by repeating in stentorian voice, "The science is settled, the science is settled".
Just as Harry Reid once settled the Iraq conflict by repeating in reedy tones, "This war is lost, this war is lost".
My previous post: Hyperbole
Or has been said elsewhere: “Illustrate absurdity by being absurd...”
But What About The Hawaiian Volcanic Chain?
Science Frontiers ONLINE
No. 103: Jan-Feb 1996
Wandering hot spots worry geologists"Hot spots" where plumes of molten magma break through the Earth's crust appear to be wandering across the planet - a discovery that undermines many of the accepted ideas about how the Earth's tectonic plates are moving... [A] new study by Robert Duncan of Oregon State University in Corvallis and his colleagues shows that the Hawaiian hot spot has probably shifted... "People suspected that hot spots were moving," says geologist Robert Butler of the University of Arizona in Tuscon. "But the one they all wanted to hang onto was the biggest, baddest hot spot of them all - the Hawaiian hot spot."
by Betsy Mason
The August 2009 issue of National Geographic had a detailed discussion and graphics of this phenomenon. Quite humbleing, makes me not want to live anywhere near there or downwind either as they show the ash dispersion on the last 3 major eruptions of this hotspot. Even more interesting are the 18 million years worth of other hot spots. There is one really big one around the time that early homonids were supposed to have begun differentiating from the ape line around 6 million years ago. Global climate change?
Regarding the Hawaiian chain, if you look at an underwater topography you will see the sea mounts (islands that have been worn down to below sea level) run to the north west. Then about (I think the figure I have read was 43 million years ago) the direction was much more directly to the north. What would have caused such a dramatic shift in the movement of the hot spot or the earth’s crust?
How old is this article? What is this stupidity that “they all wanted to hang on to”. So far as I know, scientists have recognized the movement of the Hawaiian hot spot for quite a number of years. Another one is the island chain to the east of the Caribbean plate. There is currently an underwater volcano called Kicking Jenny, or something like that that is almost up to the surface.
1999, I think it was, in New Scientist. The movement of hotspots remains a problem and controversial.