Felsic magmatism in the southern part of Himachal Higher Himalaya is constituted by Neoproterozoic granite gneiss (GGn), Early Palaeozoic granitoids (EPG) and Tertiary tourmaline-bearing leucogranite (TLg). Magnetic susceptibility values (<3×10 −3 SI), molar Al 2 O 3 /(CaO+Na 2 O+K 2 O) (≥1.1), mineral assemblage (bt-ms-pl-kf-qtz ± tur ± ap), and the presence of normative corundum relate these granitoids to peraluminous S-type, ilmenite series (reduced type) granites formed in a syncollisional

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... ectonic setting. Plagioclase from GGn (An 10 -An 31 ) and EPG (An 15 -An 33 ) represents oligoclase to andesine and TLg (An 2 -An 15 ) represents albite to oligoclase, whereas compositional ranges of K-feldspar are moreor-less similar (Or 88 to Or 95 in GGn, Or 86 to Or 97 in EPG and Or 87 to Or 94 in TLg). Biotites in GGn (Mg/Mg+Fe t = 0.34-0.45), EPG (Mg/Mg+Fe t = 0.27-0.47), and TLg (Mg/Mg+Fe t = 0.25-0.30) are ferribiotites enriched in siderophyllite, which stabilised between FMQ and HM buffers and are characterised by dominant 3Fe 2Al, 3Mg 2Al substitutions typical of peraluminous (S-type), reducing felsic melts. Muscovite in GGn (Mg/Mg+Fe t = 0.58-0.66), EPG (Mg/Mg+Fe t = 0.31−0.59), and TLg (Mg/Mg+Fe t = 0.29-0.42) represent celadonite and paragonite solid solutions, and the tourmaline from EPG and TLg belongs to the schorl-elbaite series, which are characteristics of peraluminous, Li-poor, biotite-tourmaline granites. Geochemical features reveal that the GGn and EPG precursor melts were most likely derived from melting of biotite-rich metapelite and metagraywacke sources, whereas TLg melt appears to have formed from biotite-muscovite rich metapelite and metagraywacke sources. Major and trace elements modelling suggest that the GGn, EPG and TLg parental melts have experienced low degrees (∼13, ∼17 and ∼13%, respectively) of kf-pl-bt fractionation, respectively, subsequent to partial melting. The GGn and EPG melts are the results of a pre-Himalayan, syn-collisional Pan-African felsic magmatic event, whereas the TLg is a magmatic product of Himalayan collision tectonics.