Mineral Resource Assessment of U.S. Territories of the Caribbean Basin Archipelago including Puerto Rico, U.S. Virgin Islands and Adjacent Areas Completed

Science Issue and Relevance

A major responsibility of the USGS is to collect, analyze, and disseminate minerals information on nonfuel mineral commodities to provide background information for quantifying possible world mineral supply and integrating economic, societal, and technological mineral exploration trends with other components of mineral flow. The USGS recently prepared a probabilistic mineral resource assessment of undiscovered resources in porphyry copper deposits in Central America and the Caribbean Basin in collaboration with geoscientists from academia and the minerals industry (Gray and others, 2014). Although the area consists of discrete islands today, the present land mass was contiguous during most of the major mineralization events.

When compiling information for the assessment, literature sources suggested that Puerto Rico and adjacent areas of the Greater Antilles Region might contain significant but poorly classified mineral deposits. The region has produced gold, silver, nickel, aluminum, copper, zinc, lead, antimony, iron, manganese, and tungsten. The region also contains other metals of economic interest, including chromium, cobalt, titanium, molybdenum, and tin. Construction materials and industrial minerals such as zeolite, sand and gravel, limestone, gypsum, sulfur, barite, marl, diatomite, cement, and salt are produced, generally for domestic consumption. Significant potential for trade and investment lies currently untapped in Puerto Rico and the remainder of the region's mineral sector. An updated mineral resources assessment of the region would provide data for land use decisions.

Methods to Address Issue

This project is designed to develop a modern geoscience database for a regional mineral resource assessment of the island and adjacent areas, a mineral- environmental vulnerability and risk assessment of major exploited resources, and an application of economic analyses for selected important mineral commodities based on the principal identified deposit models. The project is broken down into the following tasks:

• Compilation and synthesis of metallic mineral deposits database  
• Development of geology and geospatial base layers
• Development, analysis, and synthesis of industrial mineral resource database
• Analysis and synthesis of large–scale baseline scientific databases: geophysics, geochemical, remotely sensed data systems
• Mineral-environmental characterization of significant watersheds