Without Hot Rock Much Of North America Would Be Underwater
Posted on June 26, 2007 at 12:01:04 am
A University of Utah study shows how various regions of North America are kept afloat by heat within Earth's rocky crust, and how much of the continent would sink beneath sea level if not for heat that makes rock buoyant.
Of coastal cities, New York City would sit 1,427 feet under the Atlantic, Boston would be 1,823 feet deep, Miami would reside 2,410 feet undersea, New Orleans would be 2,416 underwater and Los Angeles would rest 3,756 feet beneath the Pacific.
Mile-high Denver's elevation would be 727 feet below sea level and Salt Lake City, now about 4,220 feet, would sit beneath 1,293 feet of water. But high-elevation areas of the Rocky Mountains between Salt Lake and Denver would remain dry land
"If you subtracted the heat that keeps North American elevations high, most of the continent would be below sea level, except the high Rocky Mountains, the Sierra Nevada and the Pacific Northwest west of the Cascade Range," says study co-author Derrick Hasterok, a University of Utah doctoral student in geology and geophysics.
"We have shown for the first time that temperature differences within the Earth's crust and upper mantle explain about half of the elevation of any given place in North America," with most of the rest due to differences in what the rocks are made of, says the other co-author, David Chapman, a professor of geology and geophysics, and dean of the University of Utah Graduate School.
People usually think of elevations being determined by movements of "tectonic plates" of Earth's crust, resulting in volcanism, mountain-building collisions of crustal plates, stretching apart and sinking of inland basins, and sinking or "subduction" of old seafloor. But Hasterok and Chapman say those tectonic forces act through the composition and temperature of rock they move. So as crustal plates collide to form mountains like the Himalayas, the mountains rise because the collision makes less dense crustal rock get thicker and warmer, thus more buoyant.
The study -- published online in the June issue of Journal of Geophysical Research-Solid Earth -- is more than just an entertaining illustration of how continents and mountains like the Rockies are kept afloat partly by heat from Earth's deep interior and heat from radioactive decay of uranium, thorium and potassium in Earth's crust.
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9 comments:
From the knowledge I have gained from the article and the knowledge I have gained from other sources this means that North America will eventually because the heat that keeps the land above the water is provided by the earth's core. The earth core is like a fire in principle except it operates using chemicals. Eventually the fire has to be fed. Since no one will ever travel to the center of the earth eventually the flame will go out. This will result in the sinking of the land and a lost continent for future folklore.
the earth's crust is very important it is keeping many major cities from sinking eventually most of earth will be below sea level
If Earth's rocky crust ever crakced one bit, North America will be in huge trouble. The sea level will go down and start to boil because it is getting to close th the core of the Earth. The crust of the Earth is the only thing keeping us from burnimg up other that the ozone layer. If the crust if the Earth goes down, we will go down with it because of gravity! This would soon become a really bad case and there would most likely be nothing to do about it!!!
this is a very interesting topic it is amazing what the earths core does for us it keeps us above water level and heats the earth. This is a very interesting study
i never knew the earths core is what keeps many major cities from sinking.
This is very interesting because the hot crust of the Earth keeps many cities in United States above the sea level. People need to be careful because no one knows what is going to happen or when is it going to happen, so they have to prepare themselves.
i just hope that the core never dies out and we can live happily ever after. the end!
From what I have learned from this blog, we will not be living here right now in Canada if it wasn't for the earth's core. What keeps us from drowning in boiling water, is the earth's core. Thats why we always need to protect and not damage our planet.
To correct my previous comment in which i said "North America will eventually because" The correct statement is that north American will eventually flood
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