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Date submitted2016-09-08
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Date accepted2016-11-18
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Date published2017-02-26
Plume tectonics – myth or reality?
- Authors:
- Yu. I. Daragan-Sushchov
The paper is dedicated to the role of mantle plumes in the formation of large igneous provinces. From different regions of the world facts are mentioned that contradict key points of plume tectonics. Closer attention is paid to classical volcanic provinces on Hawaiian islands and in Iceland, as well as to Siberian and Deccan Traps, oceanic plateau Ontong Java, Central Atlantic magmatic province, Alfa and Mendeleev Ridges in the Arctic Ocean. A conclusion is drawn that plumes are a special case of mantle-lithospheric flows, which according to deep geophysics are often located horizontally which leaves out their plume origin. Heated masses of mantle substance under young volcanic regions or rift zones of mid-ocean ridges do not emerge from the depth in the form of a straight column, but rather have arbitrary shapes, skewing to the sides and having outgrowths, offshoots, spherical bulges. Vertically rising flows of hot magma (plumes) are not a cause, but an effect of a lithospheric split and rise of magmatic substance due to decompression. A conclusion is made that it is unproductive to exaggerate the shapes and sizes of plumes and use them to explain all the diversity of endogenous processes.
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Date submitted2016-09-21
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Date accepted2016-11-04
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Date published2017-02-26
Combined 2D inversion of electrotomographic and audio-magnetotellurgic sounding data to solve mining problems
- Authors:
- V. A. Kulikov
- A. E. Kaminskii
- A. G. Yakovlev
Electrical methods of exploration are widely applied in prospecting and estimation of ore mineral resources. It is not always that geoelectrical models obtained in the course of interpretation of different types of electric and electromagnetic sounding are in line with each other. This leads to difficulties in geological interpretation of electrical exploration results. In single cases a geological model can be built that with great precision satisfies data from different electrical explorations, for instance, results of geometric and inductive electromagnetic soundings. For this purpose an algorithm of combined inversion of electrotomographic and audio-megnetotellurgic sounding data has been developed and implemented by A.E.Kaminskii in software ZondRes2D. Advantage of combined inversion has been shown for investigation of sections up till 400-500 m deep on synthetic models and actual field data.
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Date submitted2016-08-28
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Date accepted2016-11-04
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Date published2017-02-26
Deposits of gold-quartz formation in the Priamur province
- Authors:
- V. A. Stepanov
- A. V. Melnikov
A description of gold-quartz formation deposits in the Priamur gold province is presented. Prevalence of gold-quartz deposits defines metallogenic profile of the province and presence of numerous rich placers. Deposits are attributed to frontal, middle and near-bottom parts of the ore pipe. Frontal part of the ore pipe contains a major part of the deposits. They are small and consist of scattered quartz, feldspar-quartz and carbonate-quartz veins. The ore is characterized by erratic percentage of gold, bonanzas can be found. Gold is free, ranging from fine to big grains and small nuggets. It is associated with arsenopyrite, galenite, sometimes with antimonite. Among trace elements can be copper, mercury, antimony and arsenic. Prevalence of frontal deposits in the province points to significant prospects of finding a rich deep mineralization in the middle part of ore pipe. Middle part of the ore pipe contains intermediate and small deposits. Ore bodies are often represented by veined and veinlet-disseminated zones, sometimes zones of metasomatites. For gold-quartz ores, free native gold can commonly be found, usually of fine and very fine grain size. Among ore minerals, apart from arsenopyrite, pyrite and galenite, scheelite is frequently observed. Small deposits of near-bottom ore pipe are quite rare. Ore bodies are represented by quartz veins and zones of metasomatites. Gold is mostly free, of fine and super fine grain size. The prevailing trace element is mercury. Attribution of gold-quartz deposits to a certain part of ore pipe can facilitate more precise estimation of their pros pects. In its own turn, this will allow to choose more favorable objects for further evaluation.
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Date submitted2016-09-16
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Date accepted2016-11-12
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Date published2017-02-26
Possibilities of seismic exploration for crystalline basement study
- Authors:
- A. N. Telegin
Possibilities of seismic methods of reflected and refracted waves have been examined for the purposes of detailed study on crystalline basement structure. Investigation of depth and structure of the basement plays an important role in the exploration of various deposits. Sedimentary cover is usually associated with oil and gas reserves. Ore deposits are formed in the basement rocks, basement splits and structure of its surface have a genetic relation not only to ore minerals, but also to oil resources. Reflection seismology is one of the main seismic methods of investigating structural geometry of the sedimentation mass, forecasting its material composition and possible hydrocarbon reserves. However, its possibilities for investigating crystalline basement are limited. Basing on many years’ experience of reflection seismology and physical modeling it has been identified that actual roughness of basement surface limits the obtainable amount of waves reflected from it. Possibilities of reflection seismology for basement structure study are mostly related to investigation of discontinuous faults as diffraction objects using diffracted waves. Method of refracted waves combined with modern procedures and material processing aimed at getting dynamic seismic sections holds much significance for the basement study, especially in the process of surface mapping and, to a lesser extent, in investigating discontinuous faults. Combining seismic methods of reflected and refracted waves in basement study increases reliability of forecasting its geological structure: in particular, its surface can be well defined by means of refraction seismology, and zones of discontinuous faults are identified from diffraction objects using both reflection and refraction methods. As a result of applying both reflection and refraction seismology, an opportunity arises to carry out detailed analysis of basement structure and to predict its oil and gas content.
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Date submitted2015-12-29
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Date accepted2016-02-21
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Date published2016-06-01
Poorly studied phenomena in geoelectrics
- Authors:
- V. S. Mogilatov
Undoubtedly, modern geoelectric technologies emerge in the result of the development of traditional approaches and techniques. However of more interest is the appearance of completely new technologies based on new effects and new models of interaction of geological medium and electromagnetic field. The author does not commit to indicate principally new directions, but only wants to discuss some poorly known facts from the theory and practice of geoelectrics. The outcome of this study could be considered attracting the attention of experts to non-traditional signals in geoelectrics. The reviewed phenomena of interest, not fully implemented in practice in the author’s opinion, are field split into two polarizations: transverse electric (the ТЕ-field) and transverse magnetic (the ТМ-field), then some poorly known properties of ТМ-field, the role of bias currents, the anisotropy of horizontal resistances, the role of geomagnetic field in geoelectric sounding, the unique resolution of CSEM (Controlled Source Electro-Magnetic) techniques at sea.
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Date submitted2015-12-21
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Date accepted2016-02-19
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Date published2016-06-01
Composition, age and tectonic meaning of granite boulders in the devonian conglomerates of the north-west part of Spitzbergen
- Authors:
- A. N. Sirotkin
- A. N. Evdokimov
Identifying complexes of the early Proterozoic age in the composition of crystal foundation is a key task in studying pre-Cambrian formations of the whole of Spitzbergen and its northwestern part in particular. The territory of that region is formed by three deeply metamorphosed complexes that underwent the processes of migmatization and granitization in mid-Rifey and were broken through by granitoids of mid-Rifey and mid-Paleozoic. In their turn, the outbursts of the foundation are overlayed by terrigene rocks of the Devonian graben of Spitzbergen, conglomerates forming a large share among them. In the course of petrographic and chemical studies of such compositions, as well as isotopic characteristics of zircons from the boulders of basal conglomerates of Red Bay (D 1 ) series, the suite of Wolfberget at Cape Conglomeratodden the presence was identified of reddish (meat-red) granites of isotopic age of 1631±19 Mil years, which is comparable to late Karelian processes manifested actively across the archipelago. It is also proven that transformations of these rocks within the range of 380±42 Mil years are well associated with mid-paleozoic events, considerable restructuring of the foundation associated with them. The age range we defined is another proof of manifestation of early pre-Cambrian (late Karelian) processes in the northwestern Spitzbergen.
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Date submitted2015-12-17
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Date accepted2016-03-01
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Date published2016-06-01
Anomalous geochemistry of zircon from the Yastrebetskoe rare metal deposit (SIMS- and TOF-study)
- Authors:
- S. G. Skublov
- S.-Kh. Li
A detailed isotopic geochemical study (secondary ions mass-spectrometry – SIMS, time-of-flight mass-spectrometry – TOF) of zircon from ore-bearing syenites of the Yastrebetskoe rare metal-rare earth deposit (the Ukrainian Shield) has yielded proofs of magmatic genesis of the deposit: unaltered central parts of zircon grains typically feature characteristic magmatic spectra of REE distribution, their values of δ 18 O staying somewhat higher than the mantle value (6.5 ‰, on the average). During the final stage of forming the deposit the role of fluorine-water-bearing fluids enriched with Y, REE, Nb, Ве and heavy oxygen had increased, as directly reflected in the anomalous isotopic-geochemical characteristics of zircon rims and zones of zircon alteration (the contents of Y reaches 61874 ppm, that of Nb – 7976 ppm, Be – 1350 ppm, δ 18 O reaches 12.42‰, F – 0.7 % mass, H 2 O – 4% mass).
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Date submitted2015-11-11
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Date accepted2016-01-24
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Date published2016-05-01
Serpentines of chrysotile – pecoraite series as genesis indicators of nickel deposits in the Urals weathering crusts
- Authors:
- I. V. Talovina
- G. Khaide
Data are presented on the results of X-Ray structural and thermal analyses, data from chemical and microscopic studies of serpentines of chrysotile Mg3Si2O5(OH)4 – pecoraite Ni3Si2O5(OH)4 series from the silicate nickel deposits in the Urals. Nomenclature is updated of the studied serpentines following the regulations of the International Mineralogic Association. It is demonstrated that the studied minerals are the chief ore minerals in serpentinite zones of nickel fields. Issues are reviewed of formation of serpentines of the chrysotile-pecoraite series in conjunction with hydrothermal processes. It is suggested the two-tier structure of the Ural supergene nickel fields, where supergene upper tier has "roots" in the form of hydrothermal lower tier, which significantly expands the area of the search for new fields and opens great opportunities in this ancient district of ore.
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Date submitted2015-10-08
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Date accepted2015-12-11
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Date published2016-04-01
Rare metal granites in the structures of the Russian sector of Pacific ore belt
- Authors:
- V. I. Alekseev
Data are presented on the geology of areas of rare metal granites proliferation in the Russian sector of the Pacific Ore Belt that make one take a fresh look at the East Asian granitoid area to update its metallogeny. History is reviewed of studying rare metal granites of the Russian Far East. As a rule, these are found in the vicinity of major tungsten-stanniferous ore deposits, except much later than discovering the former, at the stages of their assessment and survey. Rare earth granites are usually missed by the geologists during the early stages of regional geological surveys due to their small size, weak eroding and external similarity with earlier granites. Using the examples of the Central Polousny, Badzhal and Kuyviveem-Pyrekakay regions the structural and geological conditions are characterized of localization of rare metal granites. Comparative analysis of geological situations made it possible to formulate the areal character of manifestation of rare metal granites; their confinedness to late Mesozoic orogenic arched uplifts of bogen structures above deep granitoid batholiths; positioning in the areas where longitudinal and transversal deep laying faults cross; gravitation to the environs of pre-Cambrian median masses. Similarity of structural-geological conditions for manifestation of the well-studied ore-containing granites serves to confirm the hypothesis on the joint stage of late Cretaceous rare metal magmatism in the Russian sector of the Pacific Ore Belt and the existence in the region of a magmatic super-province – the Far East belt of rare metal granites that includes the Novosibirsk-Chukotka, the Yana-Kolyma and the Sikhote-Alin rare metal – granite provinces.
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Date submitted2015-10-06
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Date accepted2015-12-18
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Date published2016-04-01
New technology of dry benefication of fly ash from coal power plants using applied mineralogy techniques
- Authors:
- V. A. Arsentev
- E. L. Kotova
The existence of environmental and strategic need to process dumps and slagheaps of coal mining enterprises of Russia and foreign countries results in reviewing the potential of using fly ash as a technogenic mineral resource. Comprehensive studies of substance composition of fly ash from coal power plants make it possible to define rational further ways of utilizing that mineral resource substantiating the scheme of its technological secondary processing. In view of the numerous environmental problems stemming from the techniques of wet benefication and processing of that mineral resource, a technology is suggested of dry cleaning of fly ash from thermal coal power plants. Studies were carried out using a number of samples of fly ash from various power plants. The suggested criteria are used to discriminate the compounds of fly ash and quantitative and qualitative composition of particulate matter is assessed. Studies of substance composition of fly ash samples has demonstrated that the concentration of non-combusted carbon in them varies from 5 to 20 %. The principal technological procedure of cleansing in our studies was a combination of magnetic and electric separation of ash in the state of vibrational pseudo-liquefaction. It enables one to increase the throughput capacity and selectivity of the cleansing process significantly. In the result of such cleansing a stable mineral fraction is produced that contains 0.5-2.5 % of carbon, so that the purified mineral fraction can be used as a construction binding agent.
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Date submitted2015-10-07
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Date accepted2015-12-27
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Date published2016-04-01
Phase transformations in synthesis technologies and sorption properties of zeolites from coal fly ash
- Authors:
- O. B. Kotova
- I. L. Shabalin
- E. L. Kotova
Coal fly ash is generated in the course of combustion of coal at thermal power plants. Environmental problems increase sharply without disposing that industrial waste. Technologies were tested of hydrothermal synthesis of zeolites from fly ash forming during combustion of coal at thermal power plants of the Pechora coal basin and dependences were identified of the experiment conditions on physical and chemical properties of the end product. It is demonstrated that synthesizing zeolites from fly ash is the first stage of forming ceramic materials (ceramic membranes), which defines the fundamental character (importance) of that area of studies. It was for the first time that sorption and structural characteristics and cation-exchange properties of fly ash from the Pechora basin coals were studied with respect to, Ba 2+ and Sr 2+ .
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Date submitted2015-09-10
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Date accepted2015-11-10
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Date published2016-03-01
Ontogenic analysis of mineral individuals at micro- and nanolevel for the restoration of ore-forming conditions and assessment of minerals processing properties
- Authors:
- R. L. Brodskaya
- Yu. B. Marin
While organizing the ore preparation system and selecting optimal methods for minerals separation, it is necessary to take into account typomorphic characteristics and properties of minerals and their aggregates that determine mineralogical and technological features of ore types and grades. Fine-dispersed ore is included into the process flow sheet; accounting particle size becomes the determining factor in ore processing technologies. With disintegration of mineral aggregate, disclosure of intergrowths, and release of intergrowth surface, its structure is relaxed to form new bonds. Mineral individual boundary can «open an individual» for its decomposition (dissolution) or growth; it can take over the functions of grain volume conservation. Adapting the aggregate to the external environment is due to the change in orientation, length and area of boundaries of individuals and the buffer zone of their intergrowth. All structural changes in mineral aggregate proceed in accordance with the energy balance of individual boundaries and boundaries of their intergrowth; therewith, substance, crystal lattice of mineral individuals are being «refined», its defects and dislocations are being annihilated. In the process of relaxation of the structure of a mineral, another mineral can arise, which individuals can remain in a dispersed state or be capable of aggregation depending on the energy balance of their boundaries and the matrix. Ontogenetic approach to the assessment of the features of mineral individuals and aggregates serves the purpose of restoration of ore-formation environment, provides a choice of optimum conditions of the disclosure of useful component grains, when in addition to the grain size, their shape, intergrowth nature, features of the boundaries of intergrowing minerals, heterogeneities of the composition and properties of mineral individuals are taken into account. It is resulted in the appearance of new opportunities of profitable and more environmentally friendly mining, ore potential revaluation towards lowering the grade, determination of cost-effective range of components extracted simultaneously.
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Date submitted2015-08-21
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Date accepted2015-10-24
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Date published2016-02-01
Results of the 5G borehole drilling at russian antarctic station «Vostok» and researches of ice cores
- Authors:
- N. I. Vasilev
- A. N. Dmitriev
- V. Ya. Lipenkov
We produce an information about results and features of the 5G borehole drilling in Antarctic layer at Russian station Vostok. Main regularities of the change structured and physical properties by Antarctic ice layer depth, which determine mechanical and reological properties if ice, which influence to sinking of a borehole and to the maintaining of it in a working condition, the safe and competitive technologies creation for drilling of strong ice layers and the environmentally safe technology of the subglacial reservoirs unsealing. We also produce results of the ice cores researching and the paleoclimatic raws construction, which are reconstructed by the ice cores researching from Vostok station, which is compared with isotopic graph. This graph describes changes of World ocean level.
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Date submitted2015-08-22
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Date accepted2015-10-06
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Date published2016-02-01
Crisis in mica production industry of the Belomorskaya pegmatite province and perspective of its overcoming
- Authors:
- N. D. Malov
- V. V. Shchiptsov
The crisis of the Belomorian pegmatite province mica sector and perspectives of its overcoming causes and consequences of the mica sector crisis in the North-West Belomorie related to studies and a production of lamellar micaceous pegmatite is discussed. The alternative importance of the unique deposit in the Mezhozernoe (Eastern Hizovaara, Northern Karelia) – primary source of scarceness lamellar light mica is confirmed. The results of mineralogical and technological researches show that it is a promising target for mining and processing a small ferrous flake muscovite.
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Date submitted2015-08-17
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Date accepted2015-10-18
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Date published2016-02-01
Platinum specialization of supergene nickel deposits on ultramafic massifs of the Urals
- Authors:
- I. V. Talovina
This paper presents an analysis of geochemical data obtained as a result of persistent research of the Buruktal, Ufalei, Elov and others supergene nickel deposits of the Urals on the content of precious metals. Content and distribution of platinum group elements, gold and silver in oxide–silicate nickel ores are compared with their content in initial dunite-harzburgite bedrock. It was revealed that all the PGE accumulate in supergene nickel deposits. Geochemical specialization of PGE mineralization of supergene nickel deposits is determined by palladium and platinum, while in dunite-harzburgite substrate of primary ophiolitic massifs major platinoids are ruthenium, osmium and iridium. Pt/Pd ratio is generally less than 1, i.e. palladium is dominating in them with some exceptions.
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Date submitted2015-08-17
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Date accepted2015-10-12
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Date published2016-02-01
Isolation of promising areas to drill for unconventional hydrocarbons petrikovskih sediments Davydovskogo deposit Pripyat Trough
- Authors:
- E.I. Shevelev
Pripyat Trough is the only oil basin in the territory of the Republic of Belarus. Mining is carried out within the basin for 50 years. During this time, the proportion of active stocks decreased significantly, while the share of hard-to-inventories increased. Therefore, due to the depletion of traditional reserves, urgent problem arises in the study and production of unconventional hydrocarbon traps. To this type of traps are Petrikov deposits Davydov field. These deposits have low permeability and capacitive properties, but at the same time in a number of wells in the test sediment in Colon yielded commercial oil inflows. Some of the well in a certain period of development led oil from Petrikov deposits. In similar deposits Rechitsa field yielded commercial oil inflows in drilling horizontal wells with hydraulic fracturing. Until recently, the reservoir Petrikov deposits was listed among the off-balance sheet reserves after drilling – reserves transferred to the balance of C1. Therefore, the input to the development of stranded there is a need to identify the most promising area for drilling horizontal wells, followed by hydraulic fracturing. To perform this work was carried out pointwise interpretation of GIS for all wells Davydov field, the results of which built the geological and petrophysical model of the deposit. Also, the analysis of core samples, the results of drilling. Produced dismemberment Petrikov deposits on two subhorizon on the results of the interpretation of GIS and well logs. The outcome of the work performed is a recommended site for drilling.
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Date submitted2015-07-21
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Date accepted2015-09-24
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Date published2016-01-01
Tectonic development and granitoid magmatism of Northeast Asia in the late mesozoic
- Authors:
- V. I. Alekseev
The history of tectonic development and granitoid magmatism of Northeast Asia in the late Mesozoic is considered. The variety of tectonic situations and granitoid magmatism are favorable circumstances for the solution of many fundamental problems in geology, but tectono-magmatic division into districts is complicated owing to variability of the composition and the structure of the Earth’s crust. A rational approach to the tectonic division into districts of a region by the research of granitoid magmatism based on determining consolidated crust blocks with various tectonic history is offered. Pre-mesozoic and mesozoic structures of the Far East, among which primary and superimposed on the Precambrian and Paleozoic base Verkhoyansk orogeny prevails, are determined. The conclusion on the important role of middle massifs and passive margins with a thin Riphean-Paleozoic cover in geodynamic development of the Far East is drawn. The mesozoic activization of ancient structures along with young granitoid magmatism is established. The driving force of the Pacific ore belt granitization was the interaction of the Paleo-Pacific Plate and plates in Northeast Asia in the middle-late Mesozoic. The history of regional tectogenesis and granitoid magmatism in the late Triassic – Eocene (230-33,7 million years) taking into account the latest geodynamic concepts is tracked. The place in tectonic history of the Asian continental margin of plutonic and volcanic-plutonic belts is determined. Four stages of tectono-magmatic development of the Far East are established: the Jurassic and the early Cretaceous collisional, the early Cretaceous upsubduction, the late Cretaceous upsubduction-transform and the late Cretaceous – Paleogene rift-related. The directed constructive evolution of the Earth’s crust of the Far East is established: origin and building of ancient cratons on margins of the continental crust sated with granitoid intrusions, increase of a silica acidity and alkalinity of the granitoid magmas and formation of late Cretaceous ore-bearing lithium-fluoric granites at the final stage.
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Date submitted2015-07-24
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Date accepted2015-09-29
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Date published2016-01-01
Geochemical features and prospects of ore content in black slates in Tajmyr-Severnaya zem-lya gold formation
- Authors:
- A. N. Evdokimov
- V. I. Fokin
- N. K. Shanurenko
Gold content, at least twice higher than the gold percentage abundance in Earth’s crust, has been discovered in a number of black slates formations in Tajmyr-Severnaya Zemlya gold province. The article shows the measurement data on organic carbon and ore elements concentrations in carbonaceous sediments, with pyrite, being their constituent, in the region. The dependence of ore elements availability, including gold, on sulphidisation degree in rocks has been identified in an ore bundle of Golyshevskaja strata. The comparison of gold concentrations in sampled monocrystals and pyrite aggregates has been carried out. It has been empirically supported that the content of gold, lead, molybdenum, cobalt, nickel and copper normally grows with the increase of sulphides quantity. Concentrations of chromium, manganese, tin, vanadium decrease respectively; however, titanium and zinc content remains unchanged.
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Date submitted2014-12-16
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Date accepted2015-02-13
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Date published2015-06-01
Mineral resources in arctic islands of Russia
- Authors:
- A. N. Evdokimov
- A. N. Smirnov
- V. I. Fokin
There is an increased interest in the Arctic regions of the planet in recent years. Russia has the longest Arctic shelf with great prospects for hydrocarbons under its jurisdiction. So, the Arctic Islands will play a major role as an infrastructural base for development of oil and gas resources on the shelf in the Arctic Ocean in the near future. Minerals of major islands and archipelagos of the Russian Arctic: Novaya Zemlya, Franz-Josef Land, Severnaya Zemlya, the New Siberian Islands and the Wrangel Island as well as the Spitsbergen archipelago (Norway) where Russia has its own territory formally enshrined for the extraction of coal and other minerals are considered in the article.
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Date submitted2014-12-25
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Date accepted2015-02-01
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Date published2015-06-01
Deep structure and composition characteristics of the continental earth's crust geostructures on the Russian Federation territory
- Authors:
- A. S. Egorov
Principal features of deep structure and composition of the lithosphere geostructures of the continental part of the Russian Federation territory are characterized within the radial-zonal model of the Earth’s crust. The principal units of the model are megablocks (paleoplites) with ancient layered continental crust and interblock megazones (structures of tension, compression and shear), separating them. The results of the geological-geophysical modeling are presented in the form of layer by layer deep structure schemes – of consolidated basement and of the platform cover and accompanied by a set of the earth's crust sections, carried out along regional profiles, performed with the application of a deep seismic sounding (DSS) method and reflected waves of common depth point (CDP) method.