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Episodic growth of felsic continents in the past 3.7 Ga.

ABSTRACT: Continents form the most accessible parts of Earth, but their complex compositions make their origin difficult to investigate. A novel approach based on a comprehensive compilation of samarium-neodymium isotopic compositions of detrital sedimentary rocks is here used to unravel continental growth through time. This record reveals that continents were as felsic as today in the past 3.7 Ga (billion years) and that their growth was not continuous but episodic. Reworking of preexisting crust was a ubiquitous process during most of Earth history, but at least six periods of continental growth can be identified every 500 to 700 Ma (million years) in the past 3.7 Ga. This recurrence could be accounted for by changes in tectonic plate velocities favoring periods of rapid subduction and enhanced production of juvenile felsic crust.

SUBMITTER: Garcon M

PROVIDER: S-EPMC8457669 | biostudies-literature | 2021 Sep

REPOSITORIES: biostudies-literature

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Episodic growth of felsic continents in the past 3.7 Ga.

Garçon Marion M

Science advances 20210922 39

Continents form the most accessible parts of Earth, but their complex compositions make their origin difficult to investigate. A novel approach based on a comprehensive compilation of samarium-neodymium isotopic compositions of detrital sedimentary rocks is here used to unravel continental growth through time. This record reveals that continents were as felsic as today in the past 3.7 Ga (billion years) and that their growth was not continuous but episodic. Reworking of preexisting crust was a u ...[more]

PMID: 34550745

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Dataset Information

Episodic growth of felsic continents in the past 3.7 Ga.

Publications

Episodic growth of felsic continents in the past 3.7 Ga.

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