Evidence from Hawaiian volcanoes shows that Earth recycles its crust

Nov 29, 2006
Earth

A geologist at Rutgers, The State University of New Jersey, has come up with evidence our planet practices recycling on a grand scale.

Writing in the prestigious British science journal Nature, geological sciences professor Claude Herzberg offers new evidence that parts of the Earth’s crust that long ago dove hundreds or thousands of kilometers into the Earth’s interior have resurfaced in the hot lava flow of Hawaiian volcanoes.

“This concept has been a big issue in the earth sciences,” Herzberg said. While it had been proposed earlier by some geologists, the profession hasn’t embraced it because evidence until now remained sketchy. “Many geologists felt that when Earth’s crust was forced deep into the mantle, a process called subduction, it would simply stay there.”

Herzberg claims to have found telltale chemical evidence at Mauna Kea that pieces of this submerged crust have been forced up through plumes and now make up most of this volcano’s lava flow. “The low calcium in the Hawaiian magma pegs it as crust that had melted and been forced to the surface,” he said. The calcium levels in traditional magma, which comes from melting the Earth’s mantle layer below the crust, are much higher.

Herzberg said his research doesn’t stop in Hawaii and that his chemical findings will be useful in understanding the makeup and action of other volcanoes around the world. These findings extend beyond calcium and include sulfur, along with isotopes of the heavier elements hafnium and lead that are tracers for clays and other materials that originated close to the surface prior to subduction.

“Chemical patterns we’ve found elsewhere used to be puzzles but are now starting to make sense,” he said.

Still, the big island of Hawaii remains the prime site for uncovering the secrets of volcanic action, as it has the largest volcanoes on Earth and is the most productive in terms of lava outpouring. Herzberg believes the information he’s uncovered about magma chemistry might one day help scientists predict eruptions, as different chemical abundances show up at different times in the volcanoes’ eruption cycles.

Source: Rutgers, the State University of New Jersey

Explore further: More than 2,200 confirmed dead in Nepal earthquake

Related Stories

Boron-based atomic clusters mimic rare-earth metals

Apr 17, 2015

Rare Earth elements, found in the f-block of the periodic table, have particular magnetic and optical properties that make them valuable commodities. This has been particularly true over the last thirty years ...

World's largest asteroid impact site could be in Australia

Apr 07, 2015

Not long ago, asteroid impacts weren't considered as a significant factor in the evolution of Earth. Following the Late Heavy Bombardment, which pummelled the inner solar system around 3.8 billion to 3.9 billion ye ...

Recommended for you

Did Kathmandu shift? Questions and Answers

3 hours ago

The tremor which struck Nepal on Saturday, killing more than 3,500 people, may have caused a land area around the capital Kathmandu to budge by several metres, experts say.

More than 2,200 confirmed dead in Nepal earthquake

Apr 26, 2015

A powerful aftershock shook Nepal on Sunday, making buildings sway and sending panicked Kathmandu residents running into the streets a day after a massive earthquake left more than 2,200 people dead.

Nepal quake: Nearly 1,400 dead, Everest shaken (Update)

Apr 25, 2015

Tens of thousands of people were spending the night in the open under a chilly and thunderous sky after a powerful earthquake devastated Nepal on Saturday, killing nearly 1,400, collapsing modern houses and ...

User comments : 0

Please sign in to add a comment. Registration is free, and takes less than a minute. Read more

Click here to reset your password.
Sign in to get notified via email when new comments are made.