Zircon U-Pb age and geochemical characteristics of granodiorite from the Haxiyatu iron-polymetallic ore district in Eastern Kunlun

Abstract: The Haxiyatu iron-polymetallic deposit is one of the typical deposits with the contribution of mantle-derived components in East Kunlun region. The authors carried out LA-ICP-MS zircon U-Pb dating of main and trace elements in the granite porphyry. LA-ICP-MS dating of zircons from the quartz diorite yielded an age of 246.8±1.8 Ma (MSWD=0.074), suggesting that the rock was formed in middle Triassic and should belong to metaluminous high potassium calc alkaline series, characterized by obvious fractionation of REE, enrichment of LREE and slightly negative Eu anomaly. The granodiorite is enriched in LILE (such as Rb, Ba and K), and relatively depleted in HFSE (such as Ta, Nb and Ti). According to lithological and geochemical characteristics as well as geotectonic background in the same period, the granodiorite was probably produced in Mesozoic magmatic arc environment, with the same source material from the crust-mantle mixing as the quartz diorite. In other strata of skarn mineralization potential, due attention should be paid to granodiorite mineralization in future prospecting work.