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The paper reports the results of study of the main placer-forming minerals (ilmenite and zircon) from the Umyt’ya coastal–marine placer in the western part of the Khanty-Mansi Autonomous District, Yugra. Microprobe study of 1450 zircon grains taken from the upper and lower ore bodies of the Umyt’ya placer (29 samples) and their comparison with zircon in magmatic rocks from the adjacent folded framing of the North and Nether-Polar Urals (40 analyses) allowed us to recognize five geochemical types of the mineral: Aurbakh (prevailing in the Umyt’ya placer), Severorudnichnyi, Tagil-Kytlym, Shemur, and unknown source. Crystallomorphological characteristics of the identified geochemical types of zircon are given. According to the microprobe data (300 analyses), ilmenite is subdivided into six groups. Comparison of these groups with the composition of ilmenite from magmatic complexes of the North and Nether-Polar Urals showed that they correspond to the same complexes as zircon. Based on peculiarities of the geological structure of the eastern slope of the North and Nether-Polar Urals, four separate areas were identified, each comprising spatially close magmatic complexes regarded as possible sources for ore minerals of the placers: Shchekur’ya–Khorasyur, Yalpigner–Chistop, Vizhai–Ivdel, and Denezhkin Kamen. Based on additional criteria, the Yalpigner–Chistop area was the main source for the Umyt’ya placer.

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.

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.

The lithofacies and morphostructural analyses of the Mansi and North Sos’va areas of the Transural placer region allowed us to establish factors of the spatial and lithostratigraphic control of titanium-zirconium placer potential. It was established that the placers are localized in sediments of the upper stage of the Oligocene-Miocene complex and rocks of Oligocene basin shows facies zoning. The most promising are the paleolittoral and shoal facies formed under moderate hydrodynamic activity. In tectonic aspect, the position of promising areas and their lithofacies composition are controlled by flank zones of local domes that experienced epeirogenic movements. Regressive regime in the Oligocene basin suggests the highest probability for the discovery of titanium-zirconium placers of the littoral type in inner zones of neotectonic domes.

In the Transural placer region of the western Khanty-Mansi autonomous district (KHMAD), Oligocene-Miocene rocks with titanium-zirconium potential are represented by mineralogically mature coastalmarine sediments. Source of placers are represented by both the Uralian weathering crust and placers of older sedimentary rocks. Sedimentation pattern of this period was governed by tectonic activation of the Uralian mountain system and sequential regressive dislocation of coastal lines from west to east. Location of perspective sectors was controlled by peripheral segments of local domes of the third order. Study of the mineral composition of sediments confirms the presence of two diverse (in mineralogy) Cenozoic terrigenous associations—(i) mature oligomictic association mainly composed of quartzose silty-sandy sediments with minerals of the titanium-zirconium assemblage (Oligocene-Miocene Complex) and (ii) polymictic (Neopleistocene) association dominated by unstable minerals and rock fragments. In terms of the set of lithofacies criteria, Oligocene-Miocene rocks are most perspective for the discovery of coastal-marine titanium-zirconium placers.