Late Devonian–Early Permian A-type granites in the southern Altay Range, Northwest China: Petrogenesis and implications for tectonic setting of “A2-type” granites

Late Silurian–early Devonian adakitic granodiorite, A-type and I-type granites in NW Junggar, NW China: Partial melting of mafic lower crust and implications for slab roll-back

“…In these regions late Silurian-early Devonian plutons are widespread (Filippova et al, 2001;Yuan et al, 2007;Kröner et al, 2008;Sun et al, 2008;Gao et al, 2009;Cai et al, 2011;Shen et al, 2011). Eby, 1992;Whalen et al, 1996;King et al, 1997;Förster et al, 1997Förster et al, , 2006Tang et al, 2010;Yuan et al, 2010;Shen et al, 2011;Li et al, 2014). Eby (1992) subdivided A-type granites into two sub-types, of which A 1 -type granites are restricted to anorogenic settings (e.g.…”

“…Silurian-Devonian granitoids are widely distributed in the CAOB and have been used to discriminate the geological evolution and crustal growth (Filippova et al, 2001;Yuan et al, 2007;Kröner et al, 2008;Sun et al, 2008;Gao et al, 2009;Chen et al, 2010;Cai et al, 2011;Shen et al, 2011). reported late Silurian-early Devonian plutons in NW Junggar including A-type granite and associated diorites, K-feldspar granites, and subvolcanic rocks that indicate that middle Paleozoic magmatism was active in West Junggar.…”

Zircon REE patterns and geochemical characteristics of Paleoproterozoic anatectic granite in the northern Tarim Craton, NW China: Implications for the reconstruction of the Columbia supercontinent

“…First proposed by Loiselle and Wones (1979), A-type granites were originally defined as having anorogenic, alkaline, and anhydrous attributes. Previous studies indicated that such granites may form by various magmatic processes, including fractional crystallization of mantle melts, partial melting of mantle or crust, AFC processes (crustal assimilation and fractional crystallization), and magma mixing between basaltic and crustal melts (e.g., Collins et al, 1982;Clemens et al, 1986;Whalen et al, 1987;Creaser et al, 1991;Turner et al, 1992;King et al, 1997;Frost and Frost, 1997;Frost et al, 1999;Wu et al, 2002;Yang et al, 2006;Dall'Agnol and de Oliveira, 2007;Bonin, 2007;Shen et al, 2010). Given the distinct geochemical signatures of A-type granites, several discrimination diagrams are commonly used to distinguish them from other types of granites (Whalen et al, 1987;Eby, 1990;Barbarin, 1999;Bonin, 2007).…”

The Paleozoic tectonic evolution and metallogenesis of the northern margin of East Junggar, Central Asia Orogenic Belt: Geochronological and geochemical constraints from igneous rocks of the Qiaoxiahala Fe-Cu deposit

“…12f; Q. Shen et al, 2011). The Nb and Ta enrichments of the Qiaoxiahala aplite imply such juvenile crustal materials may be the early arc-related Nb-enriched basaltic rocks, which have been discovered by Zhang et al (2006).…”

“…The high SiO 2 and extremely low MgO suggest that the aplite was unlikely to be generated by direct melting of the mantle, which would produce mafic to intermediate magmas (Taylor and McLennan, 1985). In the northern margin of East Junggar, there are very few mafic-ultramafic rocks that are closely related in time or space to the extensive A-type granitic magmatism (e.g., Bulgen, Kouan and Wutubulake A-type granite belts; Tong et al, 2006Tong et al, , 2012Zhou et al, 2009;Shen et al, 2011), which implies that extensive fractional crystallization was unlikely to have happened.…”