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Earlier reconstructions of climatic and environmental changes from data of deep-water drilling on the Akademichesky Ridge in Lake Baikal were based both on the content of biogenic silica or the abundance of diatom valves and on the results of X-ray diffraction (XRD) analysis of the sediment mineralogy. It was established that clay minerals are the main carrier of information about climatic variations in a drainage basin. The content of biogenic silica strictly correlates with two chrystallochemical parameters: the abundance of smectite beds in illite-smectite and the abundance of illite. However, detailed analysis of clay minerals calls for exclusive XRD techniques without mass determination of minerals in the sediments of long Baikal cores. We propose a new approach to determine the mineral composition of bottom sediments, based on their chemical composition. We compared the average chemical compositions of Pleistocene, Pliocene, and Miocene core sediments from the boreholes BDP-96 and BDP-98 and sediments of the Paleo-Barguzin River avandelta and recognized groups of chemical elements marking warm and cold climatic periods. However, the difference in the chemical compositions of sediments in warm and cold periods is insignificant. Since an XRD analysis of mineral composition is usually performed for short time intervals, it was necessary to identify cold and warm intervals by the mineral composition calculated from the chemical composition of sediments. The mineral contents were estimated using the Selektor software. Based on the average contents of chemical elements, we computed the mineral composition of the bottom sediments throughout the BDP-98 section and studied its warm and cold periods. We have established that feldspars weakly respond to climatic changes, their contents show minor variations in warm and cold epochs, whereas the contents of mica minerals change seriously. Thus, clay minerals, together with biogenic silica, are a good indicator of paleoclimatic environmental changes.

The discussion involves the issues relating rational development of natural noble metal placers and the placer mining waste, their resource potential and basic trends in mining, processing and beneficiation. It is found that the determinants of profitable development of a technogenic object (mine waste) is its pre–restructuring aimed at generation of a new structure and at increase in value of the reserves adapted to the chosen mining and processing technologies. The author substantiates the necessity and advisability of innovative technologies for placer mining waste development based on formation of concentration zones of commercial value components in dumps. The developed ways of technology modernization for gold washing machines enable increase in recovery of gold and other valuable associate components within a single work cycle.

The authors give brief information on Inaglinskaya mine planning within the Inaglinsky open pit mining lease in the South Yakutia Coal Basin and report the outcomes of technical–and–economic analysis of the mine construction and operation. The article presents formulation and solution of the problem on lag modeling and optimization of the mine design capacity.

The authors prove feasibility and efficiency of high–strength solid stone wire saw cutting in rock mass with subvertical and low–angle joints as well as drilling–and–wedge cutting of stone into marketable size blocks on the working site. The article presents and substantiates the procedure for rational selection of technology for high–strength stone preparation for cutting, considering geological conditions (shape of mineral body, orientation and spacing of joints), local temperature, as well as physico-mechanical properties and mineralogical composition of rocks.

The mathematical model is developed for describing temperature variation in soil body surrounding subway stations and tunnels, considering seasonal variation of air flow, soil freezing-thawing and induced heat flow from the subway. Using the finite element method, the authors calculate temperature field in soil body surrounding subway stations and tunnels at various depths under change in the atmospheric air temperature. Based on the numerical experiments, the thermal effect of shallow subway stations and tunnels on the surrounding soil body is estimated. The article offers the estimation procedure for delineation of influence zone of subway structures on temperature of surrounding soil. It is found that the zone of thermal effect of a subway structure grows with the depth of the subway structure occurrence. The dimension of the mentioned zone is conditioned by amount of heat produced in the underground structures of subway.

For recovery of iron oxides from disseminated iron ore, the flotation technology is developed based on using organophosphorus compounds as primary collectors. Selective preliminary removal of impurities and iron oxide flotation from wet magnetic separation tailings and directly from fine disseminated hematite ore ensures production of quality hematite-martite concentrates with the iron content of 64–66%. The option of by-production of gold from quartz present in hematite flotation tailings is illustrated.

The authors compare collecting activity of carboxylic acids and surface pressures of their film on water surface. It is found that these parameters correlate, and the surface pressure of the films depends on the length, saturation and branching of hydraulic radical and the availability of substituents. The problem on liquid removal from the film between air bubble and mineral particle is solved numerically. It is shown that the bulk force on the liquid in the film is conditioned by the surface pressure of molecules. The force of a flotation agent is defined as the force of the agent on the liquid in the film. The volumetric liquid flow from the film is related with the surface tension of agent forms active at the particle–bubble interface. The authors suggest the method of estimating collecting activity of physically attached agents by the value of force the agent exerts on liquid in the film.

The authors generalize the research aimed at integrated production of nanomaterials. Mixes of metal ions are concentrated and separated in ion flotation. In micellar solutions of extracted ions, nanoparticles of metals or their oxides are obtained. Nanoparticles are converted in nanomaterials. The article discusses physico–technical problems of ion flotation, production of nanoparticles in direct micelles and properties of nanomaterials.

The author state feasibility of deep sulfidation of rebellious oxidized lead and zinc minerals under calcinations with pyrite concentrate in the aqueous vapor environment. It is shown that interaction between oxidized lead and zinc compounds and iron sulfide in the superheated vapor with sulfide formation takes place at the solid-gas interface, namely, MO–H₂S–under sulfidation of heterolyte and beudantite; PbSO₄–H₂S–under sulfidation of plumbojarosite.

The article offers the entropy method for detecting contamination clusters and anomalous high toxic substance content in water bodies of a mineral mining region in terms of Bunguro–Chumysh district in Kuzbass. Specificity of composition of various water kinds and their ingredients is identified, diagnostic signs of various contamination sources are revealed, integral characteristics obtained from combinations of water ingredients are ranked, and distribution of ingredients in various kind water relative to MAC value is analyzed.