Research progresses on marine sandstone copper deposit and some existent problems A comparative study of the Katanga copper mine in Central Africa and the Dongchuan copper mine in Yunnan

Marine sandstone-hosted copper deposits constitute one of the most important copper deposits in the world, and most of them occur in giant Neoproterozoic and Permian sedimentary basins.The orebodies are usually stratified and stratoid in clastic or marine carbonate rock formations with multi-layered metallogenic characteristics.Based on the research status of marine sandstone-hosted copper deposits, the authors reviewed the research results of the Katanga copper belt and the Dongchuan copper belt discovered in recent years in the aspects of metallogenic material source, metallogenic fluid property, source, transportation and metal element precipitation mechanism, and found that the basin-brine-metallogenic model of epigenetic mineralization has gradually replaced the original sedimentary-transform model.Two copper deposit belts belong to the Proterozoic sand shales-dolomitic carbonate-black carbonaceous shales.The orebody has obvious stratigraphic characteristics, and is controlled by fold, fault and breccia.A comparison of the two copper belts in the aspects of ore-bearing structure and mineralization characteristics reveals that the Dongchuan copper deposit has a high degree of similarity to the Katanga copper deposit in that they both have the characteristics of basin-brine-metallogenic model.Then, the existing problems in the study of genetic type, metallogenic mechanism and fluid source from marine sandstone copper deposit and the Dongchuan copper deposit are discussed.