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Date submitted2014-08-16
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Date accepted2014-10-14
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Date published2015-02-01
Oil and gas exploration strategy in evaluation of fuel and energy potential of Russian arctic shelf
- Authors:
- V. B. Archegov
- Yu. V. Nefedov
Oil and gas are the most important resources of the Arctic region. Oil and gas prospecting, exploration and development in the Arctic region is associated with solving complex technical and technological problems. One of the most important achievements was the discovery of the global Arctic zone of oil and gas occurrence. Numerous local objects were mapped and 22 hydrocarbon deposits were found on the shelves of the Barents, Pechora and Kara Seas. In connection with the prospects of developing oil and gas exploration in other Arctic waters (the Laptev Sea, the East Siberian Sea, the Chukchi Sea) geophysical surveys and deep drilling were pro-posed to be carried out. In the area of transit shallow water it is advisable to use jack-up platforms with retractable legs. Deep drilling from islands is suggested for other parts of the seas with increasing depth and difficult ice conditions (icebergs, drifting ice fields, storms) and other climatic characteristics that increase the risk of drilling from offshore platforms. For performing hydrological and geophysical studies (studies of temperatures in layers, salinity, density, gas hydrates, and other characteristics of water in marine basins) it is possible to use «point» drilling and submarine fleet to study bottom sediments and geological section in promising areas.
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Date submitted2014-08-12
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Date accepted2014-10-11
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Date published2015-02-01
Far east belt of lithium-fluoric granites, ongonites and tin ore zwitters
- Authors:
- V. I. Alekseev
Taking into consideration published and author's data, occurrence of areas of rare-metal granitic magmatism in Central and East Asia is investigated. The Far East Belt of lithium-fluoric granites and ongonites is defined. Reasons and history of development of rare-metal granitic belts in North-east Asia are discussed. The conclusion that the Far East Belt of lithium-fluoric granites controls the largest tungstentin fields of the Far East is drawn.
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Date submitted2014-08-10
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Date accepted2014-10-14
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Date published2015-02-01
Mineralogical characteristics and spatial distribution of different age fractures in granites and pegmatites of the «Vozrozhdenie» deposit («Kawantsaari»), the Vyborg massif
- Authors:
- M. A. Ivanov
The unique size of monolithic blocks of granite in the «Vozrozhdenie» deposit («Kawantsaari») is due to the stability of these rocks in the steeply dipping and probably crosscutting part of the massif, where the rocks have retained their massive texture and have been least modified at the stage of formation of rare-metal pegmatites. The shape and size of monolithic blocks are determined by the pattern of disturbances, in the formation of which the leading role belongs to three steeply dipping zones of tectonic fractures of the North-West strike with the haloes of changes in the conditions of low-temperature acidic metasomatism. Later tectonic disruptions in these zones led to the destruction of rock blocks between them within a series of transverse fractures and to subhorizontal discontinuities of rocks caused probably by gravitational unloading of the massif and glacier action. The distribution of fractures in all directions is characterized by equal spacing («step»).
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Date submitted2014-08-14
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Date accepted2014-10-08
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Date published2015-02-01
Theoretical justification for analyzing distribution of gold concentrations in ores of hydrothermal gold deposits
- Authors:
- S. V. Sendek
- K. E. Chernyshev
The article covers theoretical justification for the analysis of the regular pattern of gold distribution within ores of hydrothermal gold deposits. The analysis is based on principles of entropy dependence of gold concentration distribution variability in different physical-chemical conditions of oreforming processes providing certain goldbearing parageneses of ore minerals. At this rate, distribution of gold concentrations in an ore paragenesis is subordinated to the log-normal rule, and, subsequently, on the binary (lognormal) scale of gold concentrations this certain paragenesis of ore minerals is reflected as the frequency maximum of one or another class of this scale. Using some methodical steps in processing channel sampling data, it is possible to reveal or confirm the presence of several gold- bearing mineral associations and compare their volumetric and quantitative ratios in orebodies and blocks of mining. Results of the performed analysis of gold concentration distribution in ores of different hydrothermal gold deposits, including the polystadial ones, prove the validity of this technique for estimation of the gold dis-tribution in ores with the purpose of carrying out supplementary study of the genetic nature of ores, and their mining feasibility.
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Date submitted2014-08-11
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Date accepted2014-10-25
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Date published2015-02-01
Geology, mineralogy and geochemistry of weathering crust of the Svetloborsky and Nizhnetagilsky massifs, the Middle Urals
The article encompasses the analysis of the mineral composition and geochemistry of weathering crusts of the Svetloborsky and Nizhnetagilsky massifs of the Ural Platinum Belt. Weathering crusts are represented by a partial profile and composed of disintegrated lizardite-chrysotile and loose leached lizardite serpentinite, which are overlapped by clays of nontronite zone at the Svetloborsky massif. The supergene process reveals accumulation of trace elements and rare earth elements (REE) upwards within the weathering profile. Rocks of the Svetloborsky massif con-tacting with dike complexes show high levels of REE content and their accumulation coefficients. In weathering profile of the Svetloborsky and Nizhnetagilsky massifs, the average content of precious metals is low; palladium and platinum prevail, in contrast to primary substrate rocks, where the main platinum group metals are platinum and iridium.
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Date submitted2014-08-13
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Date accepted2014-10-10
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Date published2015-02-01
Geochemical features of platiniferous dunites of the Svetloborsky and Nizhnetagilsky massifs, the platinum belt of the Urals
The article encompasses new data on geochemistry of dunites forming the Svetloborsky and Nizhnetagilsky ultramafic massifs of the Ural Platinum Belt. Petrogenesis of both massifs is discussed based on their interpretation. The research establishes that both massifs are petro-chemical equivalents of alpinotype complexes and zonal massifs, but at the same time they have their own particularities. Thus, dunites of the Svetloborsky massif are enriched in almost all rare elements compared to the Nizhnetagilsky massif that may be caused by their redistribution during subsequent processes due to intrusion of mafic dykes.
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Date submitted2014-08-30
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Date accepted2014-10-05
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Date published2015-02-01
Lithological and geochemical characteristics of the reef mass of ostrov Berkha (the Novaya Zemlya archipelago)
The article contains a detailed description of twelve lithogenetic types of rocks identified in the composition of the paragenetic association of the Ostrov Berkha reef mass facies: back-reef lagoon, reef flat, reef core, fore reef slope (buttress), fore reef and pinnacles. The article provides information on the structure and texture, mineralogical-petrographic and chemical fea-tures of the reef composition and surrounding sediments. The analysis of the structure of facies zones and features of their lateral changes allowed creating a model of the reef mass structure.
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Date submitted2014-08-22
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Date accepted2014-10-24
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Date published2015-02-01
On the features of the complex orthambonites pander – orthis dalman (brachiopoda) of the lost outcrops ordovician sediments on the river Pulkovka (Leningrad region)
- Authors:
- M. G. Tsinkoburova
- D. V. Bezgodova
The article analyses a complex of the Ordovician's orthida (brachiopoda) of the lost outcrops on the river Pulkovka in Leningrad region. Some samples from a large collection of brachiopods in the holdings of the Mining Museum are analysed. These samples were collected in the XIX century from some outcrops on the river Pulkovka. The geological sections there were unique outcrops due to a stratigraphic interval from the Lower Cambrian to Middle Ordovician found in them. Many early Palaeozoic marine inverte-brates, such as brachiopods, cystoideas, bolboporits, pelecypods, gastropods, were collected from these sediments. In the middle of the XX century the outcrops on the river Pulkovka were lost as a result of landsliding processes. The authors have identified an orthida's complex in the collection, comprising 12 species. The structure of the complex indicates that the stratigraphic interval, from which brachiopods were collected, can be defined as Volkhov, Kund, Azery horizons of the Middle Ordovician.
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Date submitted2014-08-17
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Date accepted2014-10-13
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Date published2015-02-01
The role of groundwater in methane formation in the coal field of Maohe (North Vietnam)
- Authors:
- S. M. Sudarikov
- Tat Tkhang Nguen
The article deals with the role of groundwater in methane formation in coal fields of North-East Vietnam using the example of Maohe deposit. Main geochemical processes during groundwater filtration in a coal bed are determined.
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Date submitted2014-08-18
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Date accepted2014-10-24
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Date published2015-02-01
Short-term pumping tests as an identification method of aquifer-surface interaction
- Authors:
- D. L. Ustyugov
- D. P. Mironchuk
Computational modeling is a convenient method of estimating underground water resources for regions with highly developed underground water resources, with a large number of variable production water supply systems. The use of computational modelling requires reliable informa-tion about a target aquifer’s filtering parameters, as well as its boundary conditions, or features of its interaction with the surface. Methods of determination of filtering parameters, including nodal analysis, which is obligatory, are well -developed, but determination of boundary condi-tions has some difficulties. The paper shows that reliable information about features of aquifer-surface interaction can be obtained by interpreting pumping tests.
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Date submitted2014-08-09
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Date accepted2014-10-20
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Date published2015-02-01
Prediction of water inflows into mine workings in the process of combined open-underground ore mining operations
- Authors:
- Yu. A. Norvatov
- M. V. Sergutin
An analysis of formation conditions of water inflows into mine workings during combined open-underground development of ore deposits was carried out. Characteristics of both natural and man-made hydro-geological structures in a copper -nickel ores «Zhdanov» deposit were identified. A method of prediction of water inflows into underground mine workings using nu-merical simulations was studied under complex hydrogeological conditions of «Zhdanov» deposit.
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Date submitted2014-08-21
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Date accepted2014-10-28
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Date published2015-02-01
Application of vertical magnetic component in magnetotelluric method to estimate parameters of anomalous objects away from the profile line
- Authors:
- E. Yu. Ermolin
- A. I. Ingerov
- Kh. M. Shaaban
The problem of estimating the effect of anomalous bodies situated away from the profile line occurs in magnetotelluric data interpretation, as well as in other geophysical methods. In this case using of magnetic-variation profiling (MVP) data is important. MVP method can be used together with magnetotelluric sounding (MTS) method. It is done by adding a channel for measuring a vertical magnetic component (Hz). MTS and MVP methods can be applied together due to the use of precise tripods. MTS and MVP methods together increase the possibility of es-timating the effect of anomalous bodies situated away from the profile line. The research target is to determine parameters of an anomalous conductive body situated away from and parallel to the profile line. This work shows how the depth of a 2D conductive body situated away from the station can be determined by tipper frequency responses (on condition the distance between the station and the body is specified). The step-by- step method for determining the depth of an anomalous body has been used in this work. The introduced method allows avoiding gross mis-takes in interpretation, as well as constructing a valid 3D model.
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Date submitted2014-08-19
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Date accepted2014-10-19
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Date published2015-02-01
Pilot electromagnetic soundings with the use of industrial power transmission line «Urengoy – Pangody» along with AMT-MT-Soundings
In 2011 and 2012 insitu electromagnetic soundings using the industrial power transmission line «Urengoy-Pangody» were taken in the Yamal-Nenets Autonomous District (YaNAD). They were conducted both in the field of the extralow frequencies (ELF) antenna «Zeus» located on the Kola Peninsula and in the fields of the natural sources (AMT-MT). Conductive layers were installed at depths of a few hundred meters and more than 1 km. These layers were linked with changes in lithology, porosity and fluid saturation of rocks. The research results showed perspectivity of complex electromagnetic sounding with natural and powerful controlled sources to find gas and oil promising horizons at a depth in the sedimentary cover of the West Siberian platform in the YaNAD.
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Date submitted2014-08-29
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Date accepted2014-10-12
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Date published2015-02-01
Potential of river electrical exploration in oil regions of the siberian platform (the Lena river area, Krivolukskaya area)
The profile line of geophysical exploration lies along the fairway of the Lena River. A complex of transient electromagnetic soundings (TES) and a common deep point (CDP) method has been used for the exploration. A complete geoelectrical section of sedimentary deposits and the properties of the basic geoelectrical layer have been estimated using TES. In the sedimentary deposits productive layer zones with increased and decreased electrical resistance have been studied. The results of both geoelectrical and seismic analyses prove that the use of both of these methods is very promising.
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Date submitted2014-08-30
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Date accepted2014-10-30
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Date published2015-02-01
Informative importance of geophysical methods for exploration of gold ore mineralization in black shale strata
- Authors:
- A. N. Orekhov
Gold ore deposits located in black shale strata are one of the main industrially significant sources of ore gold. However, using geophysical methods for exploration of these objects may lead to numerous problems caused, on the one hand, by relatively low physical contrast and, on the other hand, by the distorting effect of graphitized rocks. This article presents some insitu geophysical data from a promising area in Bodaibinsky region, their analysis and some basic conclusions.
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Date submitted2014-08-30
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Date accepted2014-10-26
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Date published2015-02-01
Numerical methods of validity estimation of electromagnetic sounding data interpretation results
The article deals with a priori and a posteriori characteristics of a degree of practical stability (practical uniqueness) of solutions to nonlinear inverse problems in geoelectrics. Numerical values of moduli of continuity of direct and inverse operators and their modifications are used as criteria of a degree of practical stability. Examples of calculation of a priori and a posteriori characteristics of a degree of practical stability of inverse problems for standard models which are used in geoelectrics are given. A dependence of characteristics of a degree of practical stability on accuracy of a descrip-tion and on input data structure, volume and level of error is examined. The obtained numerical esti-mations of a degree of practical stability of approximate solutions to inverse problems do not depend on the algorithm applied for their solving. This allows estimating accuracy and reliability of the geo-physical data interpretation results objectively.
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Date submitted2014-08-30
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Date accepted2014-10-09
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Date published2015-02-01
Prospectivity assessment of ground building materials deposits using electrologging
The article deals with an application of electrical exploration for prospecting and prospectivity assessment of ground building materials deposits. Certain correlations and laboratory measurements data on determination of electrical resistivity of ground samples were used at various stages of the research. The research results allowed calculating the volume of ground with different clay content and choosing some promising areas, whose deposits can be used as building materials.
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Date submitted2014-08-29
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Date accepted2014-10-25
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Date published2015-02-01
Application of the time-domain electromagnetic method for shallow groundwater prospecting IN Itay El-Baroud area, Nile Delta (Egypt)
- Authors:
- Kh. M. Shaaban
- Kh. Gazala
- E. Al-Saied
- G. El-Kadi
The Nile Delta is not only the oldest known ancient delta, but also is the largest and most important depositional complex in the Mediterranean sedimentary basin. Furthermore, it is a unique site in Egypt that is suitable for accumulation and preservation of the Quaternary sediments. There are very few investigations which have been carried out on the Upper Quaternary sediments of the western part of the Nile Delta. The present paper is mainly concerned with the application of the geophysical technique in the form of electromagnetic method to investigate the Quaternary sediments sequence as well as detecting the groundwater aquifer in the area of study. A site of 232 TEM sounding in 43 stations were carried out using a «SIROTEM MK-3» time-domain system. A simple coincident loop configuration, in which the same loop transmits and receives signals, was employed. The loop side length was 25 m. A 1-D modeling technique was applied to estimate the depth and the apparent resistivity of the interpreted geoelectrical data. Based on the interpretation of the acquired geophysical data, four geoelectric cross-sections were constructed. These sections show that the Upper Quaternary sequence consists of three geoelectric layers. The Holocene Nile mud is split into two layers: the agricultural root zone (Layer 1); thick water saturated mud (Layer 2). The Upper Pleistocene sandy aquifer (Layer 3) has very complicated non-linear boundary.
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Date submitted2014-08-24
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Date accepted2014-10-08
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Date published2015-02-01
The analysis of correlation relationships between results of natural electric field and chemical elements content measurements (a case study of central Urals objects)
- Authors:
- N. P. Senchina
The article analyses relationships between electrochemical processes in the weathering crust and geochemical fields to estimate the natural electric fields influence on the movement of metal ions in rocks. In situ and laboratory tests data can help to evaluate mass transfer under the influ-ence of electric fields and redistribution of chemical elements in rocks due to electrical phenom-ena. The observed dependences allow confirming the influence of the natural electric field on dif-ferentiation of elements in rocks.