This paper is the result of mineral exploration engineering.

Objective Marine iron-manganese polymetallic deposits (including iron-manganese nodules and crusts) are rich in iron and manganese resources, and also have high contents of metals such as cobalt, nickel, copper and zinc, which have important potential economic value. In addition, due to the slow growth rate of iron-manganese nodules and crusts, they are also widely used to indicate changes in the Marine environment on a million-year scale.

Methods This paper systematically reviews the composition characteristics and research progress of non-traditional stable isotopes such as iron, zinc and copper in deep-sea iron-manganese deposits in different sea areas around the world, aiming to clarify the spatial distribution characteristics of different isotopes in Marine iron-manganese deposits and their evolution trends on a million-year scale, and reveal the fractionation mechanisms of non-traditional stable isotopes such as iron, zinc and copper related to the formation of iron-manganese deposits.

Results Significant progress has been made in the study of non-traditional stable isotopes in deep-sea iron-manganese deposits, which have been successfully applied to analyzing the history and mechanism of the Marine iron cycle, reconstructing the ancient Marine environment, tracing the sources of elements, and revealing the Marine biogeochemical cycle. However, at present, the research on iron-manganese deposits still faces problems such as high analysis costs, severe regional differentiation in research areas, lagging research on diagenetic and hydrothermal iron-manganese deposits, and unbalanced attention to crusts and nodules.

Conclusions Highlighted as critical records of paleoceanographic changes, marine ferromanganese deposits exhibit distinct regional distributions in their Fe-Cu-Zn isotopic signatures. It is imperative to launch systematic studies in diverse oceanic regions to advance our understanding of their formation mechanisms and paleoenvironmental significance.