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A computer model of fractional crystallisation in mafic to intermediate igneous systems was used to calculate the phase balance and chemical characteristics of the primary magma at the Arsentyev stratified massif, which includes syenite, pyroxenite and gabbro layers. It was concluded that the concentration of apatite, titanomagnetite and ilmenite was caused by differentiation of gabbroic melt as alkalinity increased. It was connected with the late magmatic stages of liquation when the melts were rich in iron, titanium and phosphorus., A computer model of fractional crystallisation in mafic to intermediate igneous systems was used to calculate the phase balance and chemical characteristics of the primary magma at the Arsentyev stratified massif, which includes syenite, pyroxenite and gabbro layers. It was concluded that the concentration of apatite, titanomagnetite and ilmenite was caused by differentiation of gabbroic melt as alkalinity increased. It was connected with the late magmatic stages of liquation when the melts were rich in iron, titanium and phosphorus.

The distribution of gas phases within microinclusions and intergranular pore spaces of the Dovyren dunite-troctolite-gabbro intrusion has been investigated. The rocks are characterised by precious metal mineralisation related to disseminated sulphides (Stillwater type). Results showed that reduced gases (CH4 and H2) prevailed in those gases trapped by silicate minerals during their growth within the silicate magma, while oxidised gases (H2O, CO2) were less common. The abundances of reduced gases were found to increase upwards through the intrusion., The distribution of gas phases within microinclusions and intergranular pore spaces of the Dovyren dunite-troctolite-gabbro intrusion has been investigated. The rocks are characterised by precious metal mineralisation related to disseminated sulphides (Stillwater type). Results showed that reduced gases (CH4 and H2) prevailed in those gases trapped by silicate minerals during their growth within the silicate magma, while oxidised gases (H2O, CO2) were less common. The abundances of reduced gases were found to increase upwards through the intrusion.

The Ioko-Dovyren dunite-troctolite-gabbro massif is the only large well-preserved layered massif in Siberia and is known for its copper-nickel ores. High platinum group element content was found in rich Cu-Ni ores and recently low sulphide PGE mineralisation has been discovered in the middle section of the massif, mainly in anorthosites. Noble metals are distributed unevenly, but some samples contain noble metals, including gold, up to 10 ppm., The Ioko-Dovyren dunite-troctolite-gabbro massif is the only large well-preserved layered massif in Siberia and is known for its copper-nickel ores. High platinum group element content was found in rich Cu-Ni ores and recently low sulphide PGE mineralisation has been discovered in the middle section of the massif, mainly in anorthosites. Noble metals are distributed unevenly, but some samples contain noble metals, including gold, up to 10 ppm.

Apatites, phlogopites and biotites rich in Cl were found in the intrusive and metasomatic rocks of the Ioko-Dovyren massif which host low-sulphide PGE-bearing horizons. Chlorine-enriched fluid is thought to have had an important role in the formation of the mineralisation., Apatites, phlogopites and biotites rich in Cl were found in the intrusive and metasomatic rocks of the Ioko-Dovyren massif which host low-sulphide PGE-bearing horizons. Chlorine-enriched fluid is thought to have had an important role in the formation of the mineralisation.

The regional and structural geology of the Dovirensky intrusion and the mineralogy and geochemistry of the associated copper-nickel massive sulphides are described., The regional and structural geology of the Dovirensky intrusion and the mineralogy and geochemistry of the associated copper-nickel massive sulphides are described.

A model of magmatic replacement of ultrabasic differentiates of the Chaysky pluton (North Baikal region) by the latter gabbroid melt is developed on the basis of petrographic, geochemical and experimental data. The ore components are extracted from ultrabasic rocks (Ni) and gabbroid melt (S)., A model of magmatic replacement of ultrabasic differentiates of the Chaysky pluton (North Baikal region) by the latter gabbroid melt is developed on the basis of petrographic, geochemical and experimental data. The ore components are extracted from ultrabasic rocks (Ni) and gabbroid melt (S).