Ore-forming model for Cu-Au-Fe ore deposits associated with granites in the Truongson ore- forming belt of Laos

As an important part of the Tethyan metallogenic domain, Laos contains abundant mineral resources, especially rich Cu, Au, Fe, Al, and potash salt. Laos could exchange mineral advantages for economic advantages with China. The authors studied in detail the ore-forming geological background of the Truongson ore-forming belt in Laos, mineralization features and ore minerals of newly discovered porphyry Cu-Au deposits and skarn Fe ore deposits as well as their spatial relationships to the granite intrusions. On such a basis, an ore-forming model was tentatively established for the porphyry Cu-Au deposits, thus laying a foundation for building their ore-finding patterns and searching for the same ore deposits in this ore-forming belt. Based on both zircon U-Pb dating and the discrimination diagrams of Hf-Rb-Ta trace elements, it is inferred that these granites and related ore deposits might have been formed in an island arc setting developed by the subduction of the South China block beneath the Indochina block during Late Carboniferous.