Trace elements in chromite ores from the Mayari-Baracoa ophiolitic belt (eastern Cuba)

The Mayari-Baracoa ophiolite in eastern Cuba hosts more than 200 chromite deposits, grouped into three mining districts (Mayari, Sagua de Tanamo and Moa-Baracoa). Even though these chromitites are similar in appearance, they are hosted at different levels of the mantle section of the ophiolite, and they present heterogeneous geochemical composition. In situ traceelements analysis (LA-ICPMS) of unaltered chromite grains indicates that the Mayari chromitites have boninitic affinity, whereas Sagua de Tanamo and MoaBaracoa chromitites crystallized from a MORB-like liquid. This new data suggests that the ophiolitic chromitites from eastern Cuba, despite their spatial proximity, have been generated at different geodynamic settings. Mayari chromitites would have been formed underneath a nascent island arc during subduction initiation, whereas Sagua de Tanamo and Moa Baracoa chromitites would have been originated during the construction of a back-arc basin.