METALLIC MINERAL DEPOSITS OF CUBA: METALLOGENIC EPOCHS, DEPOSIT MODELS AND GEODYNAMIC ENVIRONMENT
i) mid-Jurassic-Early Cretaceous: as the North and South American portions of Pangea drifted apart, sedimentary exhalative (Sedex) Cu-Zn-Pb deposits formed in rift-related sedimentary basins.
ii) Early Cretaceous (∼135-110 Ma): a primitive Caribbean volcanic arc (boninitic and IAT series) related to west-dipping subduction of Proto-Caribbean lithosphere produced ophiolitic chromite deposits, ultramafic-hosted Au-rich massive sulfide deposits as well as bimodal-mafic and mafic type volcanogenic massive sulfide (VMS) deposits. Ophiolites of Cuba host some of the world’s richest refractory-grade chromite deposits, especially in the Moa-Baracoa ophiolite massifs, including the largest ophiolitic chromite deposit of the Americas.
iii) Late Cretaceous (pre-75 Ma): maturation of the Caribbean arc (that evolved to calcalkaline and high-K calc-alkaline series) generated epithermal precious metal deposits, small porphyry copper deposits and Fe-Cu-Au skarn deposits.
iv) Latest Cretaceous (75 Ma)-Eocene. Collision of the Caribbean arc with the Maya block and Bahamas platform (tectonic emplacement of the volcanic arc and ophiolitic units onto the continental margin) produced orogenic gold deposits.
v) Paleocene (Thanetian) to Early-Middle Eocene: An immature volcanic arc in eastern Cuba (Sierra Maestra) erupted low-K island arc tholeiites that host Cu-Zn-Au VMS deposits and volcanogenic (Cuban type) manganese deposits. In addition, iron skarn deposits (IOCG “clan”) occur in volcanic rocks near a contact with calc-alkaline plutons of intermediate composition.
vi) Late Eocene to Quaternary: Uplift exposed ophiolitic peridotite massifs to intense tropical weathering. Ni-Co laterite deposits (with some of the largest reserves in the world) formed over the serpentinized peridotites, especially in eastern Cuba and near Camagüey.