Relationship between Jinshajiang-Honghe strike-slip fault and Cu-Au polymetallic mineralization of alkaline-rich porphyry

Objective This paper is the result of mineral exploration engineering.

Objective The Jinshajiang-Honghe alkaline-rich porphyry Cu-Au polymetallic metallogenic belt, which produces numbers of large-scale Cu-Au deposits including the Yulong at the north, the Beiya in the middle and the Tongchang at the south, for example, has becoming one of the most productive ore clusters and research focus in the east Tethys domain.

Methods Based on long-term integrated field investigations and published data analysis, we summarized the characteristics of the typical deposits and the alkaline-rich porphyry.

Results The alkaline-rich porphyry mainly consists of monzonitic granite porphyry and quartz syenite porphyry, showing high contents of K₂O-Na₂O, Al₂O₃, LREE and deficit in HREE and HFSE. Similar Sr-Nd isotopic composition indicates that the source area is mainly lower crust material. The development characteristics of regional strike-slip structures and their constraints on diagenesis and mineralization in this area are also discussed, and a "regional structure→alkaline-rich magma→Cu-Au polymetallic" mineralization process controlled by the deep Jinshajiang-Honghe strike-slip fault and its secondary structure activities in the east Tethys metallogenic domain is further summarized.

Conclusions Through field observation and study on the main faults in the three typical areas, we suggest that the alkaline-rich magma and related Cu-Au mineralization were primarily controlled by the secondary northwestward faults of the regional Jinshajiang-Honghe strike-slip fault.