Earth ‘recyles’ Itself Faster Than Thought


MAINZ, Germany, Aug. 10 (UPI) — The volcanic recycling of crust that sinks due to the movement of Earth’s tectonic plates happens faster than previously thought, German researchers say.

Scientists at the Max Planck Institute for Chemistry in Mainz say sunken oceanic crust resurfaces from Earth’s mantle through volcanic eruptions after only 500 million years, a figure researchers had previously put at about 2 billion years.

Hot rock rises in cylindrical columns, so-called mantle plumes, from a depth of nearly 1,800 feet and near the surface it melts because the pressure is reduced and forms volcanoes.

The plumes originate from former ocean crust that sank to the bottom of the mantle early in the planet’s existence, and scientists had previously assumed this recycling required about 2 billion years.

Max Planck researchers found unexpected amounts of strontium isotopes in lava samples from Hawaiian volcanoes that allowed them to date the recycling process.

“Apparently strontium from sea water has reached deep in the Earth’s mantle, and reemerged after only half a billion years, in Hawaiian volcano lavas,” researcher Klaus Peter Jochum said. “This discovery was a huge surprise for us.”

UPI - United Press International, Inc.

Since 1907, United Press International (UPI) has been a leading provider of critical information to media outlets, businesses, governments and researchers worldwide.

Join the Discussion

Comment Policy: We encourage an open discussion with a wide range of viewpoints, even extreme ones, but we will not tolerate racism, profanity or slanderous comments toward the author(s) or comment participants. Make your case passionately, but civilly. Please don't stoop to name calling. We use filters for spam protection. If your comment does not appear, it is likely because it violates the above policy or contains links or language typical of spam. We reserve the right to remove comments at our discretion.