August 1, 2009

Scientists Determine Oxidation Levels Of Earth’s Plates

Researchers have discovered evidence to indicate that portions of the subduction zones where the Earth's plates collide are more oxidized than the materials erupting from mid-ocean ridges.

Writing in the journal Science, Katherine A. Kelley of the University of Rhode Island and Elizabeth Cottrell of the Smithsonian's National Museum of Natural History documented their efforts to determine the oxidation levels of minerals in different conditions.

"The seafloor is kind of like a rust conveyor belt," Cottrell told the Associated Press on Friday.

Materials become more and more oxidized as they move away from mid-ocean ridges to subduction zones.

Cottrell said the finding sheds light on the evolution of the Earth's landscape. It shows that what happens on the surface is able to dictate what happens below.

"This is a step in looking at the long-term evolution of the planet," said Cottrell.

The team used X-ray methods to determine the level of oxidation of materials in different situations.

However, the long-term consequences for the evolution of Earth remain poorly understood," Marc M. Hirschmann of the University of Minnesota, told the AP.

Cottrell and Kelley's study was funded by the National Science Foundation and the Department of Energy.


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