Abstract
Geological, petrological and geochemical studies indicated that there are two distinct types of granitoid rocks: older quartz diorites to granodiorite assemblage and younger granitoids, the latter occurring in two phases. The older granitoids have a meta-aluminous chemistry and a calc-alkaline character, with high MgO, Fe2O3, TiO2, CaO, P2O5, Sr and low SiO2, K2O, and Rb. Their major and trace elements data, together with low 87Sr/86Sr ratios (0.7029±0.0008) are indicative of I-type affinities. The second- and third-phase granitoids range from calc-alkaline to alkaline, respectively. The second-phase granitoids have a peraluminous chemistry and high Sr, Ba, CaO, MgO, Al2O3 and Ti2O and low SiO2, K2O, Nb, Y and Rb relative to the third-phase granitoids. The corundum normative nature and field observations suggested that it was formed by partial melting of the lower crust. The third-phase granitoids are alkaline in nature and characterized by higher SiO2, Rb, Y, Nb and lower MgO, Sr and Ba values than the younger granitoids (phase II). They are A-type granitoids which were generated from below or within the existing continental crust.
Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
