Zircon U-Pb age, geochemical, and Sr-Nd-O isotopic constraints on the origin of the youngest Mesozoic adakitic dikes in Jiaodong peninsula, North China Craton: implications for Early Cretaceous crustal evolution

The adakitic dikes with zircon ages of ~120–118 Ma are identified in the Xiejiagou gold deposit, Jiaobei terrain. The Early Cretaceous intermediate-acidic dikes include monzonite, quartz monzonite, and monzogranite, which have SiO2, Al2O3, K2O, Na2O contents ranging from 61.01 to 74.72 wt. %, 14.42 to 17.28 wt.%, 2.55 to 4.45 wt.%, and 3.09 to 4.64 wt.%, respectively. The dikes are enriched in large ion lithophile elements (LILEs) (e.g., Rb, Sr,...