Sea-floor massive sulphides from the Galápagos Rift Zone – mineralogy, geochemistry and economic importance

The largest reserves of the Earth's mineral resources are located on the ocean floor. Amongst these, hydrocarbon and metallic resources are of the greatest importance. In 2010, the International Seabed Authority (ISA) adopted rules for documenting new metal resources contained with polymetallic sea-floor massive sulphides (SMS). Russia and China were the first countries to apply to the ISA to acquire the right to commence initial investigation and documentation in the Indian and Atlantic oceans. Apart from copper, cobalt and nickel, modern SMS ores contain inferred significant amounts of gold, silver and PGE. The results described here from Galápagos Rift samples indicate a high concentration of gold (up to 7.24 ppm) and platinum (up to 350 ppb), which are mainly concentrated in low temperature parts of the sulphide mounds. The high content of Au and Pt revealed by this study provides further motivation towards attempting the exploration of marine massive sulphides. This is particularly important in the light of the high prices of metal commodities, and especially the unprecedented price of gold. This paper is the first such detailed scientific account in the Polish scientific literature focusing on the genesis and economic significance of the modern sea-floor sulphides.