DEC 11, 2020 6:30 AM PST

When did plate subduction begin on Earth?

New research published recently in the journal Science Advances considers the process of tectonic plate subduction. The study is a collaboration between scientists at the Scripps Institution of Oceanography at UC San Diego and the University of Chicago. It suggests that plate subduction could have initiated approximately 3.75 billion years ago.

Understanding the timeline of plate subduction will help to illuminate how life came to be on Earth. Lead author Sarah Aarons, a geochemist and assistant professor at Scripps, explains that one of the clues to configuring this puzzle is a collection of rocks from the Acasta Gneiss Complex in the Canadian tundra. The gneisses in this region date back 4.02 billion years from the Hadean eon. Aarons was particularly interested in looking at the titanium present in the ancient rocks.

"A lot of previous work has been done on these rocks to carefully date them, and provide the geochemical and petrological context," said Aarons. "We were very lucky to get the opportunity to measure titanium isotope compositions, a burgeoning isotope system in these samples."

Photo: Pixabay

By comparing the titanium isotopes in the old-gneiss samples with samples from modern rocks formed in subduction zones, she noted similarities in structure and composition. This finding points towards the initiation of the process of plate subduction around 3.75 billion years ago.

"While the trend in the titanium isotope data does not provide evidence that plate tectonics was happening globally, it does indicate the presence of wet magmatism, which supports subduction at this time," explains Aarons.

Previous studies have suggested many time periods when plate subduction could have begun – estimates range from 0.85 to 4.2 billion years ago – leaving the question still mostly unanswered. If scientists were able to answer this question once and for all, we would be able to say when Earth transitioned from transient landmasses to settled continents, later allowing for the establishment of the long-term biogeochemical cycles that are a result of volcanic degassing and recycling into Earth's interior.

Sources: Science Advances, Science Daily

About the Author
  • Kathryn is a curious world-traveller interested in the intersection between nature, culture, history, and people. She has worked for environmental education non-profits and is a Spanish/English interpreter.
You May Also Like
SEP 01, 2020
Earth & The Environment
Coral reefs diagnosed with osteoporosis
SEP 01, 2020
Coral reefs diagnosed with osteoporosis
New research published in the journal Geophysical Research Letters contemplates the impact that ocean acidification ...
SEP 11, 2020
Earth & The Environment
Almost all forest fires are caused by humans, new study reports
SEP 11, 2020
Almost all forest fires are caused by humans, new study reports
New research published in the journal Fire reports that 97% of wildfires in the US that threaten homes are started by hu ...
SEP 13, 2020
Earth & The Environment
Soil erosion exacerbates global phosphorus shortage
SEP 13, 2020
Soil erosion exacerbates global phosphorus shortage
New research published in the journal Nature Communications reports on the global phosphorus shortage that the planet is ...
OCT 23, 2020
Chemistry & Physics
The Ever-Evolving Battle to Fight Corrosion in Nuclear Reactors
OCT 23, 2020
The Ever-Evolving Battle to Fight Corrosion in Nuclear Reactors
Since its birth in the early 20th century, atomic research has brought mostly positive impacts to our lives. This week i ...
NOV 24, 2020
Earth & The Environment
Sentinel-6 Michael Freilich will extend sea level monitoring
NOV 24, 2020
Sentinel-6 Michael Freilich will extend sea level monitoring
Days ago, a new satellite was launched from Space Launch Complex 4E at Vandenberg Air Force Base in California with the ...
DEC 10, 2020
Plants & Animals
The Surprising Way Honeybees Protect Hives from Hornets
DEC 10, 2020
The Surprising Way Honeybees Protect Hives from Hornets
"Murder hornets," more commonly known as giant hornets, might be new to North America, but in their native ran ...
Loading Comments...