Orogenic and Post-Orogenic Gold Deposits: Spatiotemporal Distribution, Tectonic Controls, and Genetic Models

Orogenic gold deposits represent the most important gold resource globally after Witwatersrand-style conglomerate-hosted gold systems and have remained a major focus of economic geological research and mineral exploration over the past few decades. This review systematically summarizes the spatiotemporal distribution, geological characteristics, tectonic controls, ore-forming material sources, and genetic models of orogenic gold deposits. Orogenic gold mineralization is closely genetically related to the assembly and evolution of global supercontinents, exhibiting three prominent episodic mineralization periods at 2.8–2.55 Ga, 2.1–1.8 Ga, and 600–50 Ma. These deposits are widely developed in Precambrian cratons and Phanerozoic orogenic belts and display strong diversity in host-rock lithologies, including greenstone belts, turbidite sequences, carbonate strata, and intermediate-felsic intrusions. Corresponding mineralization styles, wall-rock alteration assemblages, and trace element zoning vary systematically with formation depth, temperature, and pressure, forming a classic epizonal–mesozonal–hypozonal crustal-continuum metallogenic framework. Compressional settings dominate traditional orogenic mineralization, with ore formation controlled by ductile–brittle shear transition, crack–seal cycles, and fluid-stress coupling at different crustal levels. Increasing evidence suggests the gold deposits may also form in post-orogenic settings under extensional conditions, where tectonic activities can reactivate pre-existing orogenic structures and facilitate fluid migration and superimposed mineralization, although this category remains debated and represents an expanded interpretation of orogenic gold systems. In terms of ore genesis, three prevailing models, namely the crustal metamorphic devolatilization model, the basin-scale two-stage carbonaceous sediment-source model, and the deep-seated metamorphic metallogenic model, have been proposed. Meanwhile, increasing evidence also indicates that magmatic–hydrothermal fluids provide indispensable material and fluid contributions to some orogenic gold systems, although metamorphic fluids remain the widely invoked fluid source for most orogenic gold deposits. This contribution provides a comprehensive theoretical review for further genetic research of global orogenic gold deposits.