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Alkali-rich intrusions associated with Cu-Mo mineralization in Baoxingchang district, displaying both felsic and mafic rock series, can be: divided into four evolution stages. LA-ICP-MS zircon U-Pb ages of the four stages intrusions 36.5∼34.6Ma, 38.0∼33.5Ma, 36.0∼34.5Ma and 34.0Ma, respectively. All the studied rocks have similar magma sources and tectonic setting. The εHf(t) values indicate that they were reworked by ancient lithospheric mantle and crustal materials via subduction. Formation of the alkaline-rich intrusions in Baoxingchang area may be involved in the processes of partial melting of mantle rocks, crust-mantle materials and fractional crystallization. It appears an increasing tendency from felsic intrusions, to enclaves and then to early-stage lamprophyre to late-stage lamprophyre.

The Baoxingchang Cu-Mo deposit is an important deposit in the Jinshajiang-Red River alkali-rich porphyry area, Western Yunnan. Fluid inclusion petrography and inclusion microscopic thermometric analysis of quartz phenocrysts in non-mineralized porphyritic granite, lamprophyre quartz veins, molybdenite quartz veins, copper-pyrite-molybdenite quartz veins, and pyrite quartz veins show that the development in primary inclusion of quartz phenocrysts and quartz veins can include vapour-rich inclusions and liquid-rich inclusions. Fluid inclusions are characterised by their medium-high temperature and moderate salinity. However, the temperature and salinity of non-mineralised quartz fluid inclusions are higher than those of quartz fluid inclusions in the mineralisation stage. Captured pressure and mineralisation depth during mineralisation reveal that the copper-molybdenum deposit is formed in hypabyssal environment, which is consistent with porphyry metalloginic systems.

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