Chronology and petrogenesis of Shijiawan granite porphyry in Shannxi Province:Constrains from zircon U-Pb geochronology and Hf isotopic compositions

The Shijiawan Mo deposit is located in Huanglongpu area of the East Qinling molybdenum belt,and its ore bodies mostly occur within the wall rocks at the exo-contact zone of Shijiawan granite porphyry. Rocks have porphyritic textures. Phenocrysts and matrixes have similar minerals,mainly composed of potassic feldspar,quartz,plagioclase and biotite. The granite porphyry is characterized by the enrichment of silica w(SiO2)=70.52%～73.04%) and alkali...