The Structure of the Earth’s Crust and Lithospheric Mantle in the Central Part of the Lower Amur Metallogenic Zone and the Gold Distribution within It

In this study, we consider the deep structure of the Earth’s crust and the lithospheric mantle in the central part of the Lower Amur metallogenic zone and its western flank, which includes the Albazino gold ore cluster. Zones with a sharp change in density and magnetic properties associated with Late Cretaceous–Early Paleogene magmatism were established based on the calculated density and magnetic depth models of the territory. A ring structure ~200 km across was identified, which is characterized by the low-density lithospheric mantle and density and magnetic inhomogeneities in the Earth’s crust, which are related with a wide development of intrusive bodies within it, as well as their spatial position and composition. The spatial relation of gold ore districts, clusters, and deposits to the density and magnetic inhomogeneities in the crust and lithospheric mantle has been analyzed and the main patterns in their distribution are shown. As a rule, they are confined to the low-density zones in the crust and marginal areas of deep-seated (12–20 km) magnetic intrusions. Based on the conclusions, new promising areas to prospect for gold deposits are proposed. In particular, it was concluded that the potential of the western part of the ring structure to the south of the Albazino deposit to host gold mineralization was underestimated.