Abstract The composition and origin of Earth’s earliest continental crust remains enigmatic due to the absence Hadean (>4 Ga) age rocks. Here we address this question by using machine learning examine provenance 4.4–3.3 Ga Jack Hills zircons, which constitute best archive crust. Our results reveal that although some zircons may be derived from trondhjemite-tonalite-granodiorite series rocks,...

Distribution patterns, petrography, whole-rock and mineral chemistry, and shape and fabric data are described for the most representative basement lithologies occurring as clasts (granule to boulder grain-size class) from the 625 m deep CRP-2/2A drillcore. A major change in the distribution pattern of the clast types occurs at c. 310 mbsf, with granitoid-dominated clasts above and mainly doleri...

Abstract The Wadi El-Hima Neoproterozoic I- and A-type granites in the Southern Eastern Desert of Egypt are rich garnets (up to 30 vol%) cut by NW–SE strike-slip faults, as confirmed from structure lineament extraction maps. These mineralized garnet mineralization zones can be successfully discriminated using remote sensing techniques. Spectral angle mapper matched filtering techniques highly e...

The Tervu breccia zone was formed at the final stages of Late Proterozoic magmatic and metamorphic activity (1.86 Ga ago) healed with granitic material shortly after its formation. agmatites has a sublatitudinal orientation, which is discordant in relation to earlier structures Kurkijoki enderbite Lauvatsaar–Impiniem diorite–tonalite complexes Svecofennian rocks Ladoga region. largest bodies th...

Modern plate tectonic brings down oceanic crust along subduction zones where it either dehydrates or melts. Those hydrous fluids or melts migrate into the overlying mantle wedge trigerring its melting which produces arc magmas and thus additional continental crust. Nowadays, melting seems to be restricted to cases of young (< 50 Ma) subducted plates. Slab melts are silicic and strongly sodic (t...

Extreme uplift associated with the formation of the 2.02 Ga Vredefort dome has exposed a substantial cross section through the crystalline early Archean basement complex rocks of the Kaapvaal craton. The rocks comprise polydeformed high-grade tonalite–trondhjemite–granodiorite (TTG) gneisses, migmatites and late-tectonic intrusive granitoids that straddle the upper amphibolite-to granulite–faci...

Eoarchean [3.6 to 4.0 billion years ago (Ga)] tonalite-trondhjemite-granodiorite (TTG) is the major component of Earth's oldest remnant continental crust, thereby holding the key to understanding how continental crust originated and when plate tectonics started in the early Earth. TTGs are mostly generated by partial melting of hydrated mafic rocks at different depths, but whether this requires...