Curtin study could rewrite Earth's history

Curtin University-led research has found new evidence to suggest that the Earth's first continents were not formed by subduction in a modern-like plate tectonics environment as previously thought, and instead may have been created by an entirely different process.

Published in the journal Geology, the research team measured the iron and zinc isotopes in rock sourced from central Siberia and South Africa and determined that the composition of these rocks may have formed in a non-subduction environment.

Lead author Dr Luc-Serge Doucet, from the Earth Dynamics Research Group in Curtin's School of Earth and Planetary Sciences, said the first continents were formed early in Earth's history more than three billion years ago, but how they were formed is still open to debate.

"Previous research has suggested that the first supercontinents formed through subduction and plate tectonics, which is when the Earth's plates move under one another shaping the mountains and oceans," Dr Doucet said.

"Our research found that that the chemical makeup of the rock fragments was not consistent with what we would usually see when subduction occurs. If the continents were formed through subduction and plate tectonics we would expect the ratio of iron and zinc isotopes to be either very high or very low, but our analyses instead found the ratio of isotopes was similar to that found in non-subduction rocks."

Dr Doucet said the team used a relatively new technique known as the non-traditional stable isotope method, which has been used to pinpoint the processes that formed continental and mantle rocks.

"Our research provides a new, but unknown theory as to how the Earth's continents formed more than three billion years ago. Further research will be needed to determine what the unknown explanation is," Dr Doucet said.

Research Report: 'Archean lithospheric differentiation: Insights from Fe and Zn isotopes'

Related Links
Curtin University
Explore The Early Earth at TerraDaily.com

Tweet

Thanks for being there;
We need your help. The SpaceDaily news network continues to grow but revenues have never been harder to maintain.

With the rise of Ad Blockers, and Facebook - our traditional revenue sources via quality network advertising continues to decline. And unlike so many other news sites, we don't have a paywall - with those annoying usernames and passwords.

Our news coverage takes time and effort to publish 365 days a year.

If you find our news sites informative and useful then please consider becoming a regular supporter or for now make a one off contribution.

SpaceDaily Monthly Supporter
$5+ Billed Monthly

paypal only

SpaceDaily Contributor
$5 Billed Once

credit card or paypal

Amber fossils reveal true colors of 99 million-year-old insects
Washington DC (UPI) Jul 01, 2020
Fossils are typically rather dull in appearance. Both the pigments and the fine structural details that give many animals their color rarely survive the ravages of times. There are, however, exceptions. Thanks to a treasure trove of ancient amber fossils recovered from amber mine in northern Myanmar, scientists are gaining new insights into the aesthetics of 99-million-year-old insects, according to a study published Wednesday. "The amber is mid-Cretaceous, approximately 99 millio ... read more