Abstract
Several lines of evidence suggest that the Archean (4.0 2.5 Ga) mantle was hotter than today's potential temperature (TP) of 1350 ° C. However, the magnitude of such difference is poorly constrained, with TP estimation spanning from 1500 ° C to 1600 ° C during the Meso‐Archean (3.2‐2.8 Ga). Such differences have major implications for the interpreted mechanisms of continental crust generation on the early Earth, as their efficacy is highly sensitive to the TP. Here, we integrate petrological modeling with thermomechanical simulations to understand the dynamics of crust formation during Archean. Our results predict that partial melting of primitive oceanic crust produces felsic melts with geochemical signatures matching those observed in Archean cratons from a mantle TP as low as 1450 ° C thanks to lithospheric‐scale Rayleigh‐Taylor‐type instabilities. These simulations also infer the occurrence of intraplate deformation events that allow an efficient transport of crustal material into the mantle, hydrating it.
Original language | English |
---|---|
Pages (from-to) | 1679-1697 |
Number of pages | 19 |
Journal | Geochemistry, Geophysics, Geosystems |
Volume | 20 |
Issue number | 4 |
Early online date | 1 Apr 2019 |
DOIs | |
Publication status | Published - Apr 2019 |
Keywords
- Continental crust
- Early Earth
- Geodynamic modeling
Fingerprint
Dive into the research topics of 'Generation of Earth's early continents from a relatively cool Archean mantle'. Together they form a unique fingerprint.Profiles
-
Richard William White
- School of Earth & Environmental Sciences - Head of School, Professor of Earth Sciences
Person: Academic