Skip to Main Content
Book Chapter

A review of the isotopic and trace element evidence for mantle and crustal processes in the Hadean and Archean: Implications for the onset of plate tectonic subduction

By
Steven B Shirey
Steven B Shirey
Department of Terrestrial Magnetism, Carnegie Institution of Washington, 5241 Broad Branch Road NW, Washington, D.C. 20015, USA
Search for other works by this author on:
Balz S Kamber
Balz S Kamber
Department of Earth Sciences, Laurentian University, Sudbury, Ontario P3E 2C6, Canada
Search for other works by this author on:
Martin J Whitehouse
Martin J Whitehouse
Laboratory for Isotope Geology, Swedish Museum of Natural History, Box 50007, Stockholm S-105 05, Sweden
Search for other works by this author on:
Paul A Mueller
Paul A Mueller
Department of Geological Sciences, Box 112120-241, Williamson Hall, University of Florida, Gainesville, Florida 32611, USA
Search for other works by this author on:
Asish R Basu
Asish R Basu
Earth and Environmental Sciences, 227 Hutchinson Hall, University of Rochester, Rochester, New York 14627, USA
Search for other works by this author on:
Published:
January 2008

Considerable geochemical evidence supports initiation of plate tectonics on Earth shortly after the end of the Hadean. Nb/Th and Th/U of mafic-ultramafic rocks from the depleted upper mantle began to change from 7 to 18.2 and 4.2 to 2.6 (respectively) at 3.6 Ga. This signals the appearance of subduction-altered slabs in general mantle circulation from subduction initiated by 3.9 Ga. Juvenile crustal rocks began to show derivation from progressively depleted mantle with typical igneous ɛNd: ɛHf = 1:2 after 3.6 Ga. Cratons with stable mantle keels that have subduction imprints began to appear by at least 3.5 Ga. These changes all suggest that extraction of continental crust by plate tectonic processes was progressively depleting the mantle from 3.6 Ga onwards. Neoarchean subduction appears largely analogous to present subduction except in being able to produce large cratons with thick mantle keels. The earliest Eoarchean juvenile rocks and Hadean zircons have isotopic compositions that reflect the integrated effects of separation of an early enriched reservoir and fractionation of Ca-silicate and Mg-silicate perovskite from the terrestrial magma oceans associated with Earth accretion and Moon formation, superposed on subsequent crustal processes. Hadean zircons most likely were derived from a continent-absent, mafic to ultramafic protocrust that was multiply remelted between 4.4 and 4.0 Ga under wet conditions to produce evolved felsic rocks. If the protocrust was produced by global mantle overturn at ca. 4.4 Ga, then the transition to plate tectonics resulted from radioactive decay-driven mantle heating. Alternatively, if the protocrust was produced by typical mantle convection, then the transition to plate tectonics resulted from cooling to the extent that large lithospheric plates stabilized.

You do not currently have access to this article.
Don't already have an account? Register

Figures & Tables

Contents

GSA Special Papers

When Did Plate Tectonics Begin on Planet Earth?

Edited by
Kent C. Condie
Kent C. Condie
Search for other works by this author on:
Victoria Pease
Victoria Pease
Search for other works by this author on:
Geological Society of America
Volume
440
ISBN print:
9780813724409
Publication date:
2008

References

Related

A comprehensive resource of eBooks for resources in the Earth Sciences

This Feature Is Available To Subscribers Only

Sign In or Create an Account

This PDF is available to Subscribers Only

View Article Abstract & Purchase Options

For full access to this pdf, sign in to an existing account, or purchase an annual subscription.

Subscribe Now