No abstract

Cluster (discrete) arrangement of minerals and their aggregates in different vectors in space is typical of most placers and deposits. Large and small pockets of valuable components in mineral bodies have different shapes, sizes, formation conditions and other geological characteristics. Cluster arrangement exists on all scales: an ore province in a region; an ore zone in an ore province; a deposit in an ore zone; an ore body in a deposit; an ore pillar in an ore body; pay zones in an ore pillar, nest, etc. By analogy with taxonomy and image identification, for differentiation of mineral resources by their processing properties or commercial value, space-detached accumulations of points representing some mineral objects are assumed as clusters with increased or lowered content of useful components. Structural order and clustering are the common features of many mineral deposits. Accurate geometrization of placers with regard to useful component content, inclusion of spatially variable quality conditions of useful components and proper management of mining favors reduction in volume of rock mass to be extracted, hauled and processed by 2 times at the same recovery factor of useful component; make it possible to increase cutoff grade by 2 times, and enables increment in production of useful component within the same production areas and at the same production capacities.

The article discusses shipment of coal to the Arctic regions of Yakutia. High transportation costs increase almost three times the price of one ton of the solid fuel. Coal fields in the Arctic have social rather than commercial value. The key target of local coal mining is enhancement of energy preparedness of population rather than money making. The review of modern methodological approaches to assessing the efficiency of using local coal resources in hard-to-reach areas reveals a wide range of such approaches, their ambiguity and neglect of the Arctic activities peculiarities. The paper presents a new approach for evaluation of small coal opencasts operating in remote Polar regions in Yakutia. The approach is based on the economic and mathematical model of substitution of local coal for imported coal. The technical and economic indicators of a small coal mine is calculated in terms of Krasnorechensky deposit of thermal coalm, and the effect of replacing imported coal by local coal in the Abyi district is evaluated. The results of the study show feasibility of in-house coal supply in the isolated and hard-to-reach areas of the Arctic by means of creation of small coal opencasts, which enhances the energy security and reduces the socio-economic tension.