SHRIMP U-Pb dating of zircons from Neoarchean crustal derived granites in the Lushan area, Shandong, China

The Lushan is one of the most famous mountain in Shandong Province, which is located in Zibo City. The crustal derived granites, with many amphibolite and diorite xenoliths, exposed in the Lushan area, were composed of coarse grained alkali-feldspar granite, fine-medium grained monzongranite and phyric monzongranite. The study of zircon SHRIMP U-Pb chronology indicated that the formation ages of the granites in the Lushan area were 2525±13Ma, 2517±13Ma and 2508±20Ma respectively. And zircons from these plutons normally have inherited cores. The granites in the Lushan area were likely to originate from crustal melting. Their formation is closely related to the strong tectonic thermal event between 2.50Ga and 2.55Ga in North China Craton, thus can be regarded as the evidence of cratonization of western Shangdong and North China during Late Neorchean.