The Red River–Jinsha
jiang strike-slip fault zone on the eastern margin of the Tibetan plateau was originally produced by the India–Eurasia collision
60–70 Myr ago. Numerous post-collisional, mantle-derived alkaline igneous rocks, with ages of
40–30 Ma, have been intruded along this fault zone. In recent years, several copper and gold deposits associated with the alkaline intrusions of this region were discovered, such as the Yao'an and Beiya gold deposits and the Yulong and Machangqing copper deposits studied in this paper. The mineralised intrusions are felsic, with SiO
2 ranging from 61.4 to 67.7 wt. % , K
2O+Na
2O from 8.1 to 11.5 wt. % and K
2O/Na
2O>1. The deposits are located at both the exo- and endo-contact zones of the intrusions. The mineral deposits are of hydrothermal origin, with the ore-forming temperatures mainly in the range 150–450 °C.