Plate Tectonics Research Rewrites History of Earth's Continents 8 July 2020

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Plate tectonics research rewrites history of Earth's continents 8 July 2020 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 Credit: Pixabay rocks. "Our research provides a new, but unknown theory as to how the Earth's continents formed more than Curtin University-led research has found new three billion years ago. Further research will be evidence to suggest that the Earth's first continents needed to determine what the unknown explanation were not formed by subduction in a modern-like is," Dr. Doucet said. plate tectonics environment as previously thought, and instead may have been created by an entirely The research was co-authored by researchers from different process. Curtin's Earth Dynamics Research Group, Université Libre de Bruxelles in Belgium, Institute Published in the journal Geology, the research for Geochemistry and Petrology in Switzerland, and team measured the iron and zinc isotopes in rock Université de Montpellier in France. sourced from central Siberia and South Africa and determined that the composition of these rocks The full paper is titled "Archean lithospheric may have formed in a non-subduction differentiation: Insights from Fe and Zn isotopes." environment. More information: Luc S. Doucet et al. Archean Lead author Dr. Luc-Serge Doucet, from the Earth lithospheric differentiation: Insights from Fe and Zn Dynamics Research Group in Curtin's School of isotopes, Geology (2020). DOI: 10.1130/G47647.1 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. Provided by Curtin University "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 1 / 2 APA citation: Plate tectonics research rewrites history of Earth's continents (2020, July 8) retrieved 26 September 2021 from https://phys.org/news/2020-07-plate-tectonics-rewrites-history-earth.html This document is subject to copyright. Apart from any fair dealing for the purpose of private study or research, no part may be reproduced without the written permission. The content is provided for information purposes only. 2 / 2 Powered by TCPDF (www.tcpdf.org).

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