The volume of water detected by the study indicates a greater probability of earthquakes, since it would represent a greater lubrication of the spaces between the tectonic plates; looks
According to a report that generates a true puzzle between the scientists, the planet is swallowing the oceans.
The movement of tectonic plates in the earth's crust is swallowing at least three times the amount of water in the oceans we thought, scientists said in an article in the journal Nature.
And in the case of the well-known Mariana Trench, the "scar" of the earth's crust that marks its deepest point, the proportion is 4.3 times the amount of water calculated so far.
Subduction is the term used by geologists to refer to the displacement of the edge of one Earth's crust plate below another. The volume of water detected by this study indicates a greater probability of occurrence of earthquakes, since it would represent a greater lubrication of the spaces between the tectonic plates.
What these researchers did was measure the seismic noise of the subduction zone of the Marianas Trench, northwest of Guam, where the Pacific Ocean plate slides under the Philippine plate.
With sound studies, they were able to estimate how much water is "filtered" in great depth with the rocks that the displacement submerges under the seabed, according to a note published by www.livescience.com.
The discovery opens new avenues for understanding Earth's deepwater cycle, according to Donna Shillington, a specialist in marine geophysics at the Lamont-Doherty Earth Observatory at Columbia University, in an article that measures the scope of the study. .
Water beneath the surface of the earth can contribute to the development of magma and can lubricate faults, making earthquakes more likely, wrote Shillington, who did not participate in the new survey.
"Subduction" was known to filter water from the bottom of the sea under the earth's crust, but not the volume of that filtration, said research group leader Chen Cai of the University of Washington in San Luis.
Chen and his team used data recorded by a network of seismic sensors located around the Mariana Trench. The deepest part of the well is almost 11 kilometers below sea level. The sensors detect earthquakes and measure their power through the intensity of their echoes in the earth's crust, which functions like a bell.
By measuring the speed of the quakes, Chen says, a deceleration would indicate more open fracture time and water-filled fractures with "hydrated" rocks and minerals.
The decelerations occurred at a depth of 18 kilometers. With data on temperature, pressure and velocity at these depths, the team calculated that the subduction "filtered" three billion teragrams of liquid per million years under the earth's crust. A teragram equals one trillion cubic meters.
Water entering the planet's mass has to come out, usually in the form of volcanic eruptions, but the new estimates change the established notion because three times the water that is calculated to be released is being filtered under the surface, and these quantities must be the same
There is something then that scientists still do not understand, so it will be necessary to continue investigating, said Chen.
The Earth's diameter is more than 12,700 kilometers, and its geothermal gradation, or progressive increase in temperature as the depth increases, is between 25 and 30 degrees Celsius per kilometer.