U-Pb Zircon dating and Geochemistry of the rocks at Wadhrai body, Nagar Parkar Igneous Complex, Sindh, Pakistan

Abstract

U-Pb zircon data for the rocks from Wadhrai body belonging to the Nagar Parkar igneous complex was acquired and processed for age dating using 207U-235Pb and 206U-238Pb isotopes. Isotopic investigations of two samples (Adamelite and Pink Granite) for U-Pb were performed using LA-ICP-MS (ArF Excimer laser ablation system with Agilent 7700x) available at CAS Key Laboratory of Crust-Mantle Materials and Environments, University of Science and Technology of China, Hefei. The processed results with 95% confidence level revealed the age of 767±12 for Adamelite and 803±7.8 Ma for Pink Granite. A total of nine samples were processed for Major, Trace, and REE elements, the results suggest the within plate granite origin for the granitic rocks, plagioclase fractionation took place as is suggested by elemental behavior in the form of Eu negative anomaly. The REE element behavior in basic magma composition rocks suggest the assimilation of crust materials during their formation. These results suggest the bimodal origin for the rocks exposed in the area, and suggest Nagar Parkar igneous exposures as the extensions of Malani Igneous Suite of Rajasthan craton.