The mechanisms behind the creation, distribution, and properties of mineral deposits are described by mineralisation genetic models, which are conceptual frameworks.
These models describe the accumulation of metals and minerals in the Earth’s crust by combining geological, geochemical, and physical processes.
The picture below highlights the genetic model of magmatic deposits. This model generally involves:
- Fractional Crystallization: segregation of minerals from a cooling magma (e.g., layered mafic intrusions like Bushveld Cr-Pt deposits).
- Liquid Immiscibility: separation of immiscible sulfide or oxide melts from silicate magma (e.g., Ni-Cu-PGE deposits in Sudbury, Noril’sk).
- Pegmatitic Processes: late-stage residual melts form rare-element pegmatites (e.g., Li, Ta, Be mineralization).
What’s the most crucial factor in forming magmatic deposits—magma composition, tectonic setting, or depth of emplacement?
Thanks to Altayeb Saad for sharing such valuable insights with us.
