Preliminary assessment of porphyry copper deposits in the Sierra Maestra, Cuba

Lukas Zurcher; Floyd Gray; Timothy Hayes; Greta J. Orris; Mark E. Gettings; Mark D. Cocker; Leila Gass

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USGS · 70212544

Preliminary assessment of porphyry copper deposits in the Sierra Maestra, Cuba

Lukas Zurcher·Floyd Gray·Timothy Hayes·Greta J. Orris·Mark E. Gettings·Mark D. Cocker·Leila Gass

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Abstract

The U.S. Geological Survey’s “three-step” form of mineral-resource assessment was used to obtain a preliminary estimate of copper resources in undiscovered porphyry deposits of the Paleogene Sierra Maestra Arc. Results of this preliminary assessment suggest that a mean of 3.2 undiscovered deposits are likely present. This estimate is comparable to results from an independently-derived porphyry deposit density model, which points to 3.9 undiscovered deposits. Monte Carlo simulation results further show that the mean estimate of undiscovered copper resources in this porphyry copper tract is in the order of 12 million metric tons. Notwithstanding having been a relatively short-lived (20-25 Ma) magmatic event, the Sierra Maestra Arc was a particularly favorable environment for the formation of porphyry copper deposits.

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Source-reported bounding extent: 19.85548° to 23.18861° latitude; -84.97491° to -74.17802° longitude. This indicates report coverage, not an exact sampling location. View area on OpenStreetMap.

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Lukas Zurcher, Floyd Gray, Timothy Hayes, Greta J. Orris, Mark E. Gettings, Mark D. Cocker, Leila Gass. 2017. Preliminary assessment of porphyry copper deposits in the Sierra Maestra, Cuba. https://pubs.usgs.gov/publication/70212544

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