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Unfortunately, the process will not be reversed in the near future by climate change caused by sea level rise.
The old oceanic bark is constantly falling in the gushing of the earth. And with it the water that she has bound in her minerals.
New research in geology at the University of Washington, St. Louis Louis discovered that this water was three times more than we thought up to here.
Part of it will come to the surface thanks to volcanoes. But it seems that the most inexhaustible geological "underground world" will never escape.
The scientific journal Nature has published the research.
Drained water
The bottom of the ocean falls in places from a depth of 9 to almost 11 km. This creates ditches of several thousand kilometers.
They connect areas where the oceanic bark is under control – in the Earth's mantle or in subduction zones.
With the oceanic bark, water that has leaked through its pores and deep fissures also falls into the depths and is now part of the so-called hydrated mineral structure.
To determine the amount of water absorbed by the Earth, they had to map the depth of expansion of these minerals. And they tried to "radiograph the Earth" by earthquakes.
New approach
The analysis of seismic wave propagation reveals the shape of the deeper structures as well as the composition of the grid of our planet. A team of geologists from the University of Washington in St. Louis has placed 19 seismographs at the bottom of the Marian sepulcher. And seven others on the neighboring islands.
The researchers wanted to verify older studies based on seismographs placed on board ships. They provide relatively inaccurate data, which extend only to a depth of about 6 kilometers.
Photo gallery / 2
The tributaries of the deep sea are bordered by places where the old oceanic bark falls into the terrestrial mantle.
Source: User Wikimedia Domdomegg
Billions of tons
More than a year listening to the spread of seismic waves has borne fruit.
It has turned out that hydrated minerals are much deeper beneath the Marian Dive. More than thirty kilometers deep. Calculations have shown that only the Marian pipeline subduction zone absorbs four times more water than we thought up to now.
The researchers note that the Marshall Dyke ocean shelf is no different from the others. This means that it is possible to deduce from new discoveries how much water is lost globally in the depths of the Earth.
"If we change the previous calculations of water absorption in subduction zones around the world to account for new discoveries, we would get 3 billion tonnes a year, three times more than we had supposed, "say the authors in their research.
How many returns?
Part of the water that descends the underlying plains of the oceanic crust up to the Earth's shell will come back to the surface by volcanic activity.
But new research shows that the amount of water absorbed can often exceed the amount of water recycled.
We do not know the exact ratio yet. This remains a challenge for future research. In particular, they will refine current estimates of the amount of water pumping volcanoes into the air as water vapor.
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