Geochemistry and Petrogenesis of the Wadhrai Granite Stock of the Malani Igneous Suite in Nagar Parkar Area, SE Pakistan

The Wadhrai granite stock is a part of the Nagar Parkar Igneous Complex, an extension Neoproterozoic Malani Suite western Rajasthan. It occupied by petrographically uniform comprising perthite, plagioclase, quartz, with small quantities biotite, opaque oxides, titanite, and secondary minerals. rocks are sparingly porphyritic contain dykes microgranite, aplite, rare pegmatite. In south-central part, parallel sheets swarms mafic dykes, in very fine-grained felsic intrude body. metaluminous to peraluminous characterized high silica (73–76 wt%), alkalis (7–9 low CaO (0.15–1.4 MgO (0.15–0.38 Th (7–12 ppm), U (1–2 ppm). On geochemical discriminant diagrams, it classifies mostly as A-type (with rather Y/Nb (8.6 2.4, average 5.2) Nb/Ga Ce (typical A2-type), but I-type. Chondrite-normalized patterns show enrichment LREE over HREE, negative Eu anomalies, whereas mantle-normalized spidergrams display higher LILE HFSE, distinct troughs for Nb, Sr, P, Ti, spikes La, Ce, Nd, Sm Tb. magma was possibly derived from tonalite-granodiorite-dominated crustal source. Based on above-mentioned evidence, interpreted that source likely developed initially continental margin subduction setting underwent partial melting extensional environment.