The Role of Multi-Stage Deformations in the Formation of the Aptian Orogenic Gold Mineralization of the Allakh-Yun Zone of the Okhotsk–Koryak Belt by the Example of the Marinskoye Deposit

Geological and structural studies carried out in the Marinskoye gold deposit of the Allakh-Yun zone of the Okhotsk–Koryak belt showed the occurrence of several deformation events and associated early and late orogenic mineralization during the Late Jurassic–Aptian subduction. The Late Jurassic stage D1 is characterized by structures of plastic deformations, greenschist metamorphism, and early orogenic gold mineralization. The structures of the second deformation stage D2 (folds of shale cleavage, crenulation cleavage) are developed locally. Brittle ore-controlling structures of the third stage D3 are superimposed on plastic deformations after their exhumation. The obtained age date of 119.4 ± 4.7 Ma (40Ar/39Ar method, sericite) of late orogenic gold mineralization is close to the age estimates of large granitoid massifs with crust–mantle sources of the Allakh-Yun zone. The Marinskoye late orogenic gold deposit was formed under conditions of compression and western transport of rocks during a change in the tectonic setting on the eastern active continental margin of the Siberian craton, related to the change in plate dynamics in the northern part of the Early Aptian Paleo-Pacific.