A new study using seismographs across the Mariana Trench has found that certain zones on earth drag down staggering amounts of water as a result of tectonic activity.
According to the new calculations, the water quantity amounts to 3 billion Tera grams every million years, with one teragram alone equaling a billion kilograms. In the new study published to the journal Nature, the researchers used data collected by 19 seismographs across the Mariana Trench.
They also looked at data from seven island-based seismographs.
This allowed for a more detailed picture of how the Pacific plate bends into the trench, revealing new insight on how the rocks hold onto water deep beneath the surface. ‘This study shows that subduction zones move far more water into Earth’s deep interior – many miles below the surface – than previously thought,’ said Candace Major, a program director in the National Science Foundation’s Division of Ocean Sciences, ‘The results highlight the important role of subduction zones in our planet’s water cycle.’
According to the team, the extreme pressure and temperature conditions cause water to become trapped in the rock as the plate travels down into the crust and upper mantle along fault lines. Previously, researchers did not have a clear picture of how deep water goes.
The researchers say the new method is far more precise, with seismic images that show the area of hydrated rock at the Mariana Trench extends nearly 20 miles beneath the seafloor.
At the Mariana Trench, the researchers estimate that four times more water is dragged into the interior for times more than previously thought.
What exactly happens to the water after it’s pulled down into the trench remains unclear. It’s thought that most returns to the atmosphere as water vapor through faraway volcanic eruptions.
Source: Daily Mail