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A mathematical model of coastal–marine tin placers formed in the alongshore drift flow is developed using the mass balance method. The physical meaning of the coefficients included in the model is considered. Coastal–marine placers are quantitatively estimated. The simulation adequacy is confirmed by the data on coastal–marine tin-bearing placer deposits at the Pevek ore cluster (Chaun Bay, East Siberian Sea). We suggest that the obtained equations be used for surveying and exploration. Identified patterns are used to estimate the tin placer potential in one of the coastal areas in the Eastern Arctic Basin.

The results of study of the Umyt’ya rare metal-titanium placer in the Transural province of West Siberia (Khanty-Mansiisk autonomous district) are presented. Lithological features of the placer-hosting Oligocene sediments were used to identify three horizons with different formation conditions and placer metal potentials. Lithofacies analysis of rocks of the upper horizon was accomplished. Comparison of the obtained results with the geophysical information (gamma and electrical logging) makes it possible to determine geological-geophysical criteria for the prospecting and exploration of rare metal-titanium placer deposits. It has been established that the gamma activity of placer-hosting rocks have a high and stable correlation with their composition (the content of minerals of the Zr-Ti assemblage included) and makes it possible to recognize separate sectors with placer bodies of mainly shallow-marine type. Electrical properties of rocks are less representative for the local prospecting, but they provide insight into the placer metal potential of separate rock horizons. Based on the identified criteria, prognostic assessment is given for the placer metal potential of deep horizons in the productive sequence of the Umyt’ya placer.

Geostatistical analysis of the composition of mineral assemblages of Oligocene sediments in the Mansi and Severnaya Sosva areas of the Transural titanium-zirconium placer district was accomplished by the method of the principal components. High significance of the first principal component and its composition revealed by this analysis suggest the existence of an efficient placer-forming process that can produce commercial concentrations of ore minerals. Interpretation of statistical indicators is given. The results confirm the facies zoning of sediments revealed previously in the Oligocene basin. They show that the paleolittoral and shallow-water zones with a moderate hydrodynamic activity in the depositional environment have the highest potential of titanium-zirconium raw material. Analysis of the mineral potential revealed that the Mansi and Severnaya Sosva areas can accommodate a medium-scale placer deposit.