Seminar

Numerous Fe-Cu-(REE) deposits are hosted in Proterozoic metasedimentary-metavolcanic successions in
SW China and NW Vietnam, forming the Kangdian IOCG metallogenic province. The Yinachang and Sin Quyen
deposits are typical of the province.

The Yinachang deposit contains economic concentrations of Fe and Cu, and is enriched in the LREE. The
ore minerals were associated with abundant F- and CO2-rich minerals. This deposit was formed at ~1700 Ma in
an intracontinent extensional setting. The mineralization was largely associated with Paleoproterozoic
magmatism. The Sin Quyen deposit contains economic concentrations of Cu, Au and LREE, and sub-economic
concentration of U. The ore minerals were associated with abundant Cl-bearing gangue minerals. The
mineralization occurred at ~840 Ma in a subduction-related (Andean-type) setting. Subduction-related
magmatism may provide abundant fluid and ore metals for mineralization.

Results in this study show that IOCG-like deposits can be produced in both intracontinent setting and
continent margins. The ore-forming tectonic environment may influence the composition of ore-forming fluids,
which in turn determine the mineralogy of ores.