Isotope geochemistry as a tool in the exploration of gold occurrences in Ghana: a review

The use of stable isotopes in other gold provinces around the world shows the usefulness of this method as a complementary tool in locating Mineralization in areas lacking visible alteration where delineation of mineralization has increasingly been a challenge. This paper reviews the use of stable isotope geochemistry in mineral exploration and discusses its possible application in the Birimian of Ghana as an auxiliary exploration technique. The types of samples utilized in the reviewed studies were bulk rock samples, mineral veins, and mineral separates. The mineralized terranes in Ghana have δ18O values falling between 13 and 21‰. The unmineralized terrane in Ghana however recorded a relatively depleted range of δ18O values between 9 and 13‰. Values from the mineralized terrane in Ghana recorded a comparably wider range of δ13C values between −15 and 11‰. This is in contrast to a narrower range of δ13C values between −3 and 1‰ recorded in the unmineralized terrane. δ34S values from the mineralized terrane in Ghana documented values of −20‰ and 8. These values revealed a discernible isotopic shift between the mineralized and non-mineralized terrane which points to the potential success for such a methodology in the Birimian of Ghana. However, due to the difficulty in recognizing rocks whose stable isotopes have been altered by metamorphic processes coupled with challenges in data interpretation, it would be more suiting to use stable isotopes method in association with other techniques such as lithogeochemistry and geophysical datasets to help better constrain the isotopic signature of the mineralization. © 2021, Saudi Society for Geosciences.