Metallogenic implications from zircon U–Pb ages and Sr–Nd–Hf isotopic geochemistry of quartz monzonite porphyry in the Habo Cu–Au deposit, southern belt of the Jinshajiang-Red River, China

Porphyry deposits show a marked tendency to occur in liner, typically orogeny-parallel belt. The Jinshajiang-Red River metallogenic belt (JRMB) is an important Cenozoic porphyry metallogenic belt in Southwest China. Interestingly, the decrease in these Cenozoic porphyry deposit sizes is obvious from north to south in the JRMB. This size decrease is considered to be related to the decrease in magmatic oxygen fugacity. However, the reason for the difference in magmatic oxygen fugacity is rarely explored. Zircon U–Pb dating and Lu–Hf and Sr–Nd isotopic tests of the quartz monzonite porphyry (QMP) in the Habo deposit to the south of the JRMB were carried out. The results show that the diagenetic age of the Habo QMP is 35 ± 0.4 Ma. The Ɛ Hf ( t ) values range from − 2.4 to 2.5. The Ɛ Nd ( t ) values range from − 4.5 to − 3.8. They are close to those of Beiya deposit, but different from Yulong. The Yulong area experienced strong collision, while the Habo area experienced obvious shearing due to the collision and compression of the India-Eurasia plate. The magma of the Yulong porphyry is derived from the melting of deep mantle or oceanic crust, while the porphyry magma in the Beiya and Habo areas is mainly from the melting of the lower crust. So, the different magma sources were produced at different tectonic settings that which leaded the magma with different oxygen fugacities (i.e., the metallogenic potential to form porphyry deposits) between the Yulong, Beiya and Habo deposits.