Abstract
Manganese is a globally significant industrial metal essential for steelmaking, battery technologies, and emerging green-energy applications. As demand increases, understanding the geological diversity, distribution, and economic context of manganese deposits is critical. Manganese deposits occur in a range of tectonic settings and include hydrogenetic, diagenetic, and hydrothermal–exhalative systems associated with ophiolites, mid-ocean ridges, back-arc basins, and sedimentary basins. These genetic types exhibit distinct mineralogical, geochemical, and isotopic signatures that reflect processes such as hydrothermal precipitation, hydrogenetic crust formation, and diagenetic remobilization. These different genetic Mn types have distinct mineralogy, major and trace element compositions, REE geochemistry, and isotopic compositions, reflecting their nature and manner of deposition. This review synthesizes global models of Mn ore formation and evaluates the major deposit types and their geotectonic associations. Emphasis is placed on the manganese occurrences of Oman's Wahrah Formation, which represent sedimentary–hydrothermal Mn accumulations hosted by radiolarian cherts within Hamrat Duru Sub-basin of the Semail Ophiolite and the Batain Basin associated with the Masirah Ophiolite. Given that manganese is now classified as a strategic raw material by the EU and USGS due to its role in low-carbon and battery technologies, this review provides timely insights into the geological controls, resource potential, and economic relevance of Mn deposits worldwide, with a focused assessment of Oman's position within the global manganese landscape