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We present geochemical characteristics of rocks and results of local dating and Lu-Hf isotopic analysis of zircons from two massifs of Paleoproterozoic collisional granitoids in the northwest of the Sharyzhalgai uplift. The rocks of the Alar intrusion in the Bulun terrane correspond in major- and trace-element composition to I -type potassic granites. The Alar granites formed at ~780 ºC and <5-8 kbar through melting of predominantly graywacke (volcanosedimentary) source rocks with the contribution of plagiogneisses of tonalite-trondhjemite complex. The age and Lu-Hf isotopic similarity between inherited zircon core (3.3-3.0 and 2.85-2.6 Ga) in these granites and zircons from the Paleo- and Mesoarchean rocks of the Bulun terrane suggests that the latter are the most likely crustal sources of the granites. The more radiogenic isotope composition of the Paleoproterozoic (1.85 Ga) igneous zircons from the granites as compared with the zircons from the Archean crustal rocks of the Bulun terrane testifies to the contribution of juvenile material to the granite formation. Highly ferroan granodiorites and granites of the Shumikha intrusion in the Onot terrane are enriched in HFSE and correspond to A -type granites. They probably derived by the melting of crustal sources of intermediate-felsic (tonalitic) and mafic composition at ≥860 ºC. The Hf isotope composition of igneous and inherited zircons indicates that the granites formed from ancient crustal source (model Hf age is >3.0 Ga) with the contribution of Neoarchean juvenile, probably mafic material.

The paper reports on seafloor terrains mapped to a high resolution, the structure of shallow-water sediments, and the extent of barite mineralization in the Deryugin Basin, Sea of Okhotsk. The data were collected by different methods of remote sounding of the bottom and a Comanche submersible in the area of the Barite Ridge deposit. The sedimentary cover, including Holocene sediments, is strongly deformed in this area and in some other areas of the basin. Several small mud volcanoes and new barite build-ups along the ridge axis are evidence of active fluid venting. Precipitated barite forms columns (chimneys) or grows over older layered barite build-ups. The research confirms the hypothesis of Ba supply by deep cold hydrotherms.

The numerical modeling provides a holist picture of mechanical treatment and activation of substances in disintegrator. The authors calculate kinematic and dynamic characteristics of elastic and inelastic collisions in terms of halite, quartz and sulfur particles and disintegrator fingers. The recommendations on selecting optimal treatment conditions for natural minerals and waste material in order to dissociate mineral concretions and for selective activation of minerals are given. The research findings can partly be used for other types of percussion disintegrating devices, in particular, jet mills.

The article focuses on concentrating of nickel from lean solutions of leaching of oxidized nickel ore. The proposed block diagram of process flow chart for such solutions includes hydrolytic removal of admixed iron and aluminium and precipitation of nickel concentrate by calcinated magnesia. The as a result, nickel content of the concentrate is 26-26% at the recovery of 95-97%. The issues of decontamination and recycling of the solutions are solved.

The article describes mineralogical and processing properties of ferruginous quartzite from Kimkan deposit. Essential nonuniformity of the composition and properties of the major metallic mineral-magnetite-should be accounted for when processes and, particularly, when selecting pretreatment method.

The authors describe studies into dressability of mill tailings from tailings pond of processing plant of Yaroslavskaya Mining Company. It is found that the mill tailings contain 14.92% of CaF₂, 13.16% of CaCO₃ and 0.49% of Zn. The use of new compositions of modifies in flotation of fluorite allows production of standard grade concentrates with the CaF₂ content of 93.19-95.54% at the recovery of 52.75-30.15%. Zinc recovery in the concentrate is 38.84% at the yield of 42.11%.

The environment protection and dust control on washed-in waste piles is complicated by the continuous replenishment of tailings and, consequently, formation of new dusting layer on the pile surface. This problem can be solved using aerosol guns-fog-projection devices within the dust suppression system. The authors propose to place the aerosol dust suppression system on a platform-car moving along a tailings dump. This allows automating dust control and increasing volume of transported water. Grain-size composition of dust at tailing dumps of Kovdor Mining and Processing Plant is determined. From the laboratory experiments, it is found how intensity of dust transfer abates dust suppression. The experimental findings make it possible to calculate the required number of jets for an aerosol gun.

Mining and processing industry forms mining landscape. Reclamation of mined-out areas is an efficient way of the environment protection in mining regions. It is rational to make mining-disturbed lands suitable for further use by taking mineral mining and processing waste. Justification of technology of placing waste in the mined-out void of Vostochny open pit of Magnitogorsk Metallurgical Plant at Magnitnaya Mountain (Chelyabinsk Region) is based on the analysis of hydrodynamic and hydrochemical history of the project, laboratory studies into interaction of backfills with quarry water and prediction modeling of change of conditions in the course of backfilling the open pit by means of modeling hydro-geomigration.

Geophysical methods of detecting places of spontaneous heating in mined-out voids in gently dipping and inclined coal bed in Kuzbass mines are reviewed. The emphasis is laid on the method of equatorial dipole sounding used to determined temperature of coal in the place of spontaneous heating in Olzherasskaya Novaya Mine. The cooling time of the coal and rock nest down to the temperature of surrounding rock mass is estimated, and the self-heating seat suppression actions are proposed.

Samples of rocks with different physico-mechanical properties (three kinds of granite, marble and quartzite) were subjected to destruction by impacts. Fractoluminescence was recorded on the damaged surface, and amplitudes and frequencies of series of light pulses were determined. On all test samples, initiation of inter-grain cracks was observed. Defects on the surface of grains in granite samples had two typical sizes conformable with defects in quartz and spar, while uniform content minerals (marble and quartzite) features unimodal distribution of sizes of defects on the surface of grains.