Abstract:
:Understanding Hadean (>4 Ga) Earth requires knowledge of its crust. The composition of the crust and volatiles migrating through it directly influence the makeup of the atmosphere, the composition of seawater, and nutrient availability. Despite its importance, there is little known and less agreed upon regarding the nature of the Hadean crust. By analyzing the 87Sr/86Sr ratio of apatite inclusions in Archean zircons from Nuvvuagittuq, Canada, we show that its protolith had formed a high (>1) Rb/Sr ratio reservoir by at least 4.2 Ga. This result implies that the early crust had a broad range of igneous rocks, extending from mafic to highly silicic compositions.
journal_name
Proc Natl Acad Sci U S Aauthors
Boehnke P,Bell EA,Stephan T,Trappitsch R,Keller CB,Pardo OS,Davis AM,Harrison TM,Pellin MJdoi
10.1073/pnas.1720880115subject
Has Abstractpub_date
2018-06-19 00:00:00pages
6353-6356issue
25eissn
0027-8424issn
1091-6490pii
1720880115journal_volume
115pub_type
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