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Trovati due immensi oceani
all'interno della Terra, che se trovassero una via di
uscita, invaderebbero tutte le terre emerse.....ma fino
all'altro giorno non dicevano i nostri "scienziati" che, man
mano che si entra verso il centro della terra la temperatura
aumenta....???? evidentemente si sono sbagliati....
Fonte:
http://www.kp.ru/daily/23882.4/65610/
Un enorme “oceano” d'acqua,
delle dimensioni del Mar Glaciale Artico, è stato scoperto a
centinaia di chilometri sotto l'Asia orientale, questa la
relazione dei ricercatori.
I ricercatori hanno trovato l’oceano, mentre osservavano la
scansione di onde sismiche, mentre passavano attraverso
dell'interno della Terra. Ma nessuno andra’ ad esplorare
questo mare da sotterraneo. L'acqua è bloccata in umidità
nelle rocce a 400-800 miglia (da 700 a 1.400 km), sotto la
superficie del globo.
"Non è un oceano vero e proprio. L'acqua è in una
percentuale molto bassa nella roccia, probabilmente meno
dello 0,1 per cento". Date le dimensioni della zona,
tuttavia, che basta per raggiungere una grande quantità di
acqua.
Huge Underground "Ocean" Found
Beneath Asia
A giant blob of water the size
of the Arctic Ocean has been discovered hundreds of miles
beneath eastern Asia, scientists report.
Researchers found the underground "ocean" while scanning
seismic waves as they passed through Earth's interior.
But nobody will be exploring this sea by submarine. The
water is locked in moisture-containing rocks 400 to 800
miles (700 to 1,400 kilometers) beneath the surface.
"I've gotten all sorts of emails asking if this is the water
that burst out in Noah's flood," said the leader of the
research team, Michael Wysession of Washington University in
St. Louis.
"It isn't an ocean. (The water) is a very low percentage
(of
the rock), probably less than 0.1 percent."
Given the region's size, however, that's enough to add up to
a vast amount of water.
A
map depicts large areas of wet underground rock (shown
in red) as detected by seismic waves. Scientists
studying these waves discovered a giant "ocean" of water
under east Asia that contains about as much water as the
Arctic Ocean. -
Map courtesy Eric Chou/WUSTL
Earthquakes Reveal "Ocean"
Wysession and former graduate student Jesse Lawrence
discovered the damp spot by observing how seismic waves from
distant earthquakes pass through Earth's mantle.
The wet zone, which runs from
Indonesia to the northern tip of Russia, showed up as an
area of relatively weak rock, causing the seismic waves to
lose strength much more rapidly than elsewhere (see
map of Asia.)
The water got there by the process of plate tectonics, in
which sections of the Earth's crust shift. This process
caused the ocean bottom to be pulled beneath continental
plates all around the Pacific Rim.
Normally, Earth's internal heat bakes the water out of the
rocks before it gets more than 60 miles (100 kilometers)
deep. The water then escapes upward as volcanic gas.
But along the eastern Pacific Rim, conditions allow the rock
to be drawn much deeper before the moisture is cooked out.
The find may help scientists better understand the formation
of volcanic regions such as those in Iceland, Hawaii, and
Yellowstone National Park.
(Read related story:
"Supervolcano Raises Yellowstone, Fuels Geysers, Study Says"
[March 1, 2006].)
One theory suggests that these areas are volcanic because
hot spots deep within the Earth's interior melt the
underlying rock like a giant blowtorch, producing large
quantities of lava.
Wysession says that the presence of water may allow such hot
spots to melt more rock, thereby creating more lava.
"If you add water [to the rock] you can get an increased
amount of melting," he said. "There's a consensus that
not all hot spots are equal. Some are hot spots; some are
wet spots."
Wysession and Lawrence report their findings in a study
published by the American Geophysical Union.
A Look at Earth's Fate
The new study also reveals clues to Earth's long-term fate,
says Norman Sleep, a geophysicist at Stanford University who
was not involved in the project.
When the planet was young, steam came from the deep interior
to the surface as volcanic gas and eventually produced
today's oceans. But as Earth's interior ages and cools, it
becomes easier for water to return below the surface.
"So, rather than degassing, now [Earth] may be losing water
into the mantle," Sleep said.
This gradual suction of water back below the surface may be
a good thing for Earth's geological stability, he notes.
Underground water acts as a kind of lubricant that allows
plates in Earth's crust to keep shifting at their present
rate, Sleep explains.
This helps keep the thickness and elevation of the
continents relatively stable.
If things changed, he said, "we'd have Pike's Peak boat
tours."
By Richard A. Lovett
for
National Geographic News February 27, 2007 - Free Email
News Updates - Best Online Newsletter, 2006 Codie Awards
http://news.nationalgeographic.com/news/2007/02/070227-ocean-asia.html
vedi:
ESPANSIONE
della TERRA: http://www.expanding-earth.org/
http://www.normanspencer.co.nz/PsEarthScience/GlobesAmerica.html
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