摘要
The Yulekenhalasu porphyry copper-(molybdenum) deposit occurs in the diorite porphyry, porphyroid quartz monzonite, and volcanic rocks of the Beitashan Formation. Mineralization occurs as veinlet, veinlet- disseminated and stockwork. The ore-forming processes can be divided into three mineralization periods: porphyry, shear deformation and supergene. 40Ar/39Ar dating was performed on the muscovite and biotite, which yielded two plateau ages of (283.8±1.5) Ma and (277.0±2.0) Ma, and isochron ages of (285.4±3.1) Ma and (277.0±4.0) Ma, respectively. Two plateau ages are coincident with the isochron ages within error, which reflect the ductile shearing deformation in the ore district took place in the Early Permian (284~277) Ma. The ductile shearing deformation age in the Yulekenhalasu ore deposit is coincident with the age of Irtysh-Mayinebo fault belt. The porphyry Cu-(Mo) mineralization took place in the Middle Devonian (374 Ma), while the ductile shearing deformation in the Early Permian reformed the Cu-(Mo) ore deposit.