A new study has revealed that the Western United States is sitting over a vast expanse of melting carbon, some 217 miles below its surface. According to scientists, the molten carbon is spread over an area close to 700,000 square miles.
This was borne by experiments in the region using an array of advanced seismometers. Thanks to the carbon melting at the underground, changed seismic patterns were detected by the sensors with images that showed some variations in the upper mantle.
"It would be impossible for us to drill far enough down to physically 'see' the Earth's mantle, so using this massive group of sensors we have to paint a picture of it using mathematical equations to interpret what is beneath us," said Sash Hier-Majumder, a geologist at University of London's Royal Holloway, who led the study.
The seismic analysis has been published in the journal Earth and Planetary Science Letters.
Subduction Of Tectonic Plate
Explaining the cause of carbon melting, researchers said it was the result of the submerging of Pacific tectonic plates underneath the Western region of the United States. The rocks that went beneath came under intense heat and pressure from the mantle and subsequently melted.
The study made an accurate estimate of the amount of carbon holed up at the upper mantle as 100 trillion metric tons.
Majumder added that it is natural that enough thought has not gone into the Earth's deep structure in the matter of climate change. The new discovery of huge carbon deposits will have many implications on subterranean mapping and future atmosphere.
He said the deep carbon reservoir showed the critical role played by deep earth in the global carbon cycle. According to the researcher, even a 1 percent release of the stored carbon dioxide into the atmosphere will equal the burning of 2.3 trillion barrels of oil.
The study explains the way a huge network of close to 600 seismic sensors measured the vibrations of Earth while mapping the deep subsurface of the area. The upper mantle is noted for the extreme temperature that makes solid carbonates melt away.
The molten reservoir of liquid carbonate was also abetted by the presence of carbon dioxide and water in the dissolved minerals.
EPA Projections On Emission
Thanks to the study, it is now understood that the volume of carbon dioxide in the Earth's upper mantle comes to about 100 trillion metric tons average.
The paradox is that the new discovery of massive carbon deposits makes the projection made by the U.S. Environmental Protection Agency of 10 billion metric tons of global carbon emission totally insignificant.
The research also says that in the time to come, the underground carbon will make it to the earth's surface and move into the atmosphere by means like volcanic eruptions and exacerbate the climate change issue.