PALEOPROTEROZOIC A-TYPE MAGMATISM IN THE CENTRAL INDIAN TECTONIC ZONE (CITZ): INSIGHTS FROM THE DUDHI GRANITOID COMPLEX (MAHAKOSHAL BELT), INDIA
The Dudhi Granitoid Complex, situated within the Mahakoshal Belt of the Central Indian Tectonic Zone (CITZ), comprises Paleoproterozoic granites. This Mahakoshal Belt is one of the most significant Paleoproterozoic supracrustal belts in the central India, preserving a complex record of geological, tectonic, and metallogenic evolution. Despite its importance, the Paleoproterozoic granites of this belt remain poorly understood, particularly with respect to their petrogenesis and tectonic setting. This study presents new whole-rock geochemical and zircon U–Pb geochronological data for A-type granites to constrain their magma generation and geodynamic evolution. The studied rocks are high-silica, ferroan, metaluminous, with enrichment in light rare earth elements (LREE). Zircon U–Pb dating yields a concordant emplacement age of ca. 1.76–1.73 Ga. Geochemical data signatures indicate that the A-type granites were derived from partial melting of the lower crust source during a post-collisional to intraplate extensional regime. These results provide new insights into the Proterozoic crustal evolution of the Mahakoshal Belt within CITZ and have implications for the assembly of the Columbia supercontinent.
Keywords: A-type granites, U–Pb geochronology, Dudhi Granitoid Complex, Mahakoshal Belt (MB), Central Indian Tectonic Zone (CITZ), Columbia supercontinent.