LA-ICP-MS zircon U-Pb dating and Hf isotope analysis of the Qinggangping granodiorite in Xixia area of western Henan Province and their geological significance

Caledonian granitoids are well developed in western Henan Province. The study of these granites is of great significance for understanding the Erlangping Rock Group and the orogenic process of the North Qinling orogen. This paper presents zircon geochronologic data, zircon Hf isotopic and related whole-rock geochemical analyses of a typical granitoid pluton in Qingangping area of western Henan Province, and gives the following results and understanding: The Qinggangping granitoid pluton in western Henan Province has a crystallization age of 475.2±2.7 Ma. This age can be used to constrain the emplacement time of Erlangping ophiolite. The Qinggangping granitoids have relatively low MgO, Fe2O3, Cr and Ni content and Mg number. These geochemical characteristics show that the granitoid should be the product of a thickened lower crust by partial melting. It can also be concluded that convergence-collision probably occurred in North Qinling in Early Paleoproterozoic period.