Publication Date:
2019
Description:
〈p〉This paper descibes the petrology, geochemistry and petrogenesis of Archaean granitoids. Archaean granites define a continuum of compositions, between several end-members: (i) magmas that originated by partial melting of a range of crustal sources, from amphibolites to metasediments ("C-type" granitoids); (ii) magmas that formed by partial melting of an enriched mantle source, the most common agent of enrichment being felsic (TTG) melts. Differences in the degree of metasomatim results in different primitive liquids for these "M-type" granitoids.〈/p〉
〈p〉Mixed sources, differentiation and interactions between different melts resulted in a continuous range of compositions, defined by variable proportions of each end-member.〈/p〉
〈p〉During the Archaean, evolved crustal sources (sediments or felsic crust) and metasomatized mantle sources become increasingly more important, mirroring the progressive maturation of crustal segments, and the stabilization of the global tectonic system.〈/p〉
Print ISSN:
0375-6440
Electronic ISSN:
2041-4927
Topics:
Geosciences
