Scientific journal “Processes in GeoMedia” № 2 (24) 2020

GEOLOGICAL AND ELECTROMAGNETIC STUDY OF LUNDA REGION (ANGOLA)
Z. Armando, A.P. Olivio
Peoples ‘ friendship University of Russia, 117198, Moscow, Miklukho-Maklaya str. 6

Abstract. The paper is devoted to the study of the geological structure, history of geological development and tectonic zoning of the Lunda region, as well as the interpretation of electromagnetic data about it. The need to find out sedimentation conditions, terrain tectonics, and characteristics of the type of kimberlite rocks by drilling lithological wells and electromagnetic data is the Central topic of this work. Kimberlite rocks containing high-quality diamonds are widely distributed in the region. The area is dominated by a continental environment with active tectonic and magmatic activity, which contributed to the appearance of numerous intrusions and metamorphism. The study was based on data from fields and wells drilled in the Lund region. Geophysical studies have revealed anomalies associated with kimberlite bodies.
Keywords: Lunda, kimberlite rocks, transition-electromagnetic method.

FAR-EASTERN GEMSTONE PROVINCE: MINERAGENIC ZONING, SPATIAL PLACEMENT OF SEMIPRECIOUS GEMS DEPOSITS
V.G. Gadyatov, P.I. Kalugin, A.I. Demidenko
Voronezh State Technical University, 394006, Voronezh, 20 let Oktyabrya str. 84

Abstract. Mineragenic zoning of the territory of the Primorsky Kray on colored stones is carried out. The Far-Eastern gemstone province is allocated. The spatial distribution of deposits of colored stones is shown. When zoning, taxonomic units of different hierarchical levels are used as a basis. The province is taken as the largest division. The Far-Eastern province includes the Sikhote-Alin subprovince and Primorskaya region, which include the Upper-Burein, Upper-Anyu, Bikin, Dalnerechensk, Ussuri and Coastal mineragenic zones. The article describes the characteristics of ore regions with known deposits and promising manifestations of noble opal, sapphire, zircon, chrysolite, agate and garnet, which make up the mineral resource base of colored stones in Russia.
Keywords: minerageny, semiprecious stone material, zoning, field, ore district, mineragenic area, subprovince, province.

STUDY OF PSEUDO-COMPONENT MODEL OF OIL EVAPORATION ON THE SEA SURFACE SENSITIVITY TO VARIATIONS OF PARAMETERS
S.N. Zatsepa 1, A.A. Ivchenko 1, V.I. Zhuravel 1, V.V. Solbakov 2, 1
1 N.N. Zubov State Oceanographic Institute, 119034, Moscow, Kropotkinskiy per., 6
2 FRC «Computer Science and Control», 119333, Moscow, Vavilova str. 44-2

Abstract. The pseudo-component model of evaporation of oil or oil products, which is often used in calculating the mass balance in spills on the sea surface, is studied. A refinement of the evaporation model is proposed, taking into account the molecular diffusion of components in the oil layer. It is shown that taking into account diffusion processes in the oil film is important for oil film thicknesses of the order of centimeters and should be taken into account when calculating the evaporation of oil spills under ice conditions and low temperatures, when emulsions such as water in oil are formed. For oil and oil products with a wide range of boiling points, the pseudo-component molecular diffusion significantly slows down the evaporation in the first hours after the spill, which should be taken into account when calculating the gas contamination of the accident area. During the evaporation of oil, the role of turbulent exchange in the boundary layer of the atmosphere is significantly lower than during the evaporation of water or other single-component liquids. The influence on the evaporation rate of the ambient temperature, the film thickness of the oil and the chemical composition of the oil or oil product is analyzed.
Keywords: oil spills in the sea, evaporation of multicomponent liquid, mass transfer coefficient, pseudo-component model, molecular diffusion in liquid phase.

PROSPECTS FOR GEOMECHANICAL APPROACH APPLICATION TO THE DEVELOPMENT OF FIELDS WITH LOW-PERMEABILITY RESERVOIRS
V.I. Karev, Yu.F. Kovalenko
A. Ishlinsky Institute for Problems in Mechanics RAS, 119526, Moscow, Vernadskogo ave., 101-1

Abstract. This article tackles the problem of fresh water scarcity across the globe. Technological solutions to extract these resources are the key important issue. The results of experimental studies of low-permeability (the order of several mD) of reservoirs of Achimov deposits of the Urengoy gas condensate field with unique true Triaxial Independent Loading Testing System (TILTS) IPMech RAS are presented. In the experiments, the dependence of rock permeability on the stress-strain state is studied. In the rock samples real stresses that occur in the bottom-hole zone of the formation when the pressure in the well decreases for different downhole geometries: an open borehole, perforation hole in a cased well are re-created. The prospects of the geomechanical approach for creating ways to improve the quality of wells, in particular, the adaptation of the directed reservoir discharge method for the conditions of this deposit, are shown. The research is important both in scientific terms and in practical terms – to justify technical and technological solutions for the development of deposits with unconventional reserves.
Keywords: rock, well, perforation hole, test system, permeability, stress, fracture, anisotropy.

SOUND GENERATION IN THE MARINE ENVIRONMENT BY A BEAM OF HIGH-ENERGY PARTICLES
A.V. Kistovich
WSC «All-Russian Scientific Research Institute of Physical-Technical and Radio-Technical Measurements», 141570, Moscow region, Mendeleevo

Abstract. asymptotic solution to the problem of thermal-radiation excitation of sound by a beam of high-energy particles inhibited in the marine environment in a pre-known region of space-time is presented. It is explicitly shown that the directivity diagram of such a sound source for experimentally observed modes of beam deceleration has its maximum near the plane perpendicular to the axis of the deceleration area. The system of eigenfunctions of acoustic radiation is of the N-wave type. The validity of the embedded models and the results obtained using this approach was checked in the limiting case of a semi-infinite braking region with a uniform longitudinal intensity of the excitation pressure. This allowed us to determine an adequate version of the physical model of the process, which provided an exact match with the known results in this limit case.
Keywords: heating zone, thermal-radiation excitation, acoustic N-wave.

DEVELOPMENT TECHNOLOGY FOR PRIOBSKOYE FIELD WITH LOW PERMEABILITY OF PRODUCTIVE FORMATIONS
Liu Chen
Tomsk Polytechnic University, 634050, Tomsk, Lenina ave. 30

Abstract. The paper makes a retrospective analysis (since 1990) of changes in specialists’ ideas about validation of reasonable systems for development of low-permeability (for example, < 10 mD) objects of large and unique oil fields of KMAD – Yugra: Priobskoye ULT1, Priobskoye SLT2 , Prirazlomnoye, Tailakovskoye, Malobalykskoye, Em-Egovskaya area of Krasnoleninskoye field, etc. For reference, it should be noted that the accumulated oil production in 2016 by low-permeability reservoirs (LPR) of these fields have exceed 700 million tons. The Priobskoye field has low well flow rates. The main problems of the field development are low productivity of productve wells, low natural (without rupturing the formations with injected water) acceptivity of injection wells, as well as poor redistribution of pressure over the reservoirs during the implementation of RPM (due to weak hydrodynamic coupling of formation parts).
Keywords: analysis, retrospective, fields, development, drilling.

NUMERICAL SIMULATION OF SINGLE WAVE INTERACTION WITH UNDERWATER GROYNE IN A MODEL RESERVOIR
S.Yu. Mikhailichenko, E.V. Ivancha, A.Yu. Bazykina
Marine Hydrophysical Institute of RAS, 299011, Sevastopol, Kapitanskaya str. 2

Abstract. This work is focused on numerical modeling of the interaction of a solitary surface wave with an underwater rectangular breakwater in the constant depth model basin using the non-hydrostatic hydrodynamic model SWASH (Simulating WAves till SHore). The features of the transformation of a wave passing over an obstacle with a change in the width and height of the shore protection structure were investigated. Based on numerical experiments, the transformation coefficients for the soliton and the zone of its attenuation area behind a breakwater were calculated. The localization of the region of maximum attenuation of the wave passing beyond the shore protection structure is determined. The analysis of the spatial structure features of free-surface fluctuations arising as a result of the interaction of a soliton with a breakwater is carried out. The depth-averaged orbital fluid velocities are calculated and the dependence of their values and directions on the geometric parameters of the underwater obstacle is determined.
Keywords: SWASH model, soliton, transformation coefficients, underwater breakwaters, orbital fluid velocities.

INFLUENCE OF EXOGENOUS FACTORS ON HYDROGEOLOGICAL SITUATION (BY THE EXAMPLE OF GO MIKHNEVO)
S.M. Petukhova
Sadovsky Institute of Geosphere Dynamics of RAS, 119334, Moscow, Ac. Zelinskogo str. 38-1

Abstract. Observations of level variations of the unconfined Kashira aquiferous horizon (Lopasny and Nara layers) and confined Aleksin-Protvino aquifer are conducted in wells located at the territory of the geophysical observatory “Mikhnevo” of Institute of Geosphere Dynamics (GO Mikhnevo) since 2007. According to hydrogeological monitoring, the features of groundwater regime formation are established, as well as the amplitudes of seasonal level variations and the duration of recharge and discharge of the aquifers of different ages are determined. Along with the influence of natural exogenous factors (precipitation, level variations of the surface water, infiltration), technogenic decrease of the level of groundwater is observed. The beginning of the spring level rise of Kashira unconfined aquiferous horizon corresponds to a temperature transition over 0 ºС. The amplitudes of the spring level rise in the Lopasny and Nara layers depend on the natural resources formed due to precipitation in the year preceding the observations. The seasonal level rise of Aleksin-Protvino aquifer is shifted in time relative to the Oka river flood. The intensity of the high water determines the amplitude of the spring level rise of confined aquifer.
Keywords: unconfined aquifer, confined aquifer, hydrological regime, precipitation, hydrogeological monitoring.

MODELLING OF THE SEVASTOPOL BAY TEMPERATURE AND SALINITY FIELDS DURING HYDROLOGICAL WINTER
К.А. Slepchuk
Marine Hydrophysical Institute of RAS, 299011, Sevastopol, Kapitanskaya str. 2

Abstract. The results of the use of the 3D version of water quality hydrodynamic cluster MECCA for temperature and salinity field representation during hydrological winter (January, February, March) in the Sevastopol Bay water area are given in this paper. Expedited data on wind and its direction, and air temperature for 2003 with 6 hour zone, as well as mean monthly data on humidity and cloud amount for 2003 are used for the modeling. The obtained results are compared with in situ data. As a result, shown is the vertical thermohaline structure which is destroyed in February leading to formation of vertical homogeneity, which is typical for near-shore areas in winter period. The conclusion about satisfactory modeling results and their use in the 3D version of water quality hydrodynamic cluster MECCA is drawn.
Keywords: numerical modelling, thermohaline structure, Sevastopol Bay.

CONSIDERATION OF THE EMPIRICAL STATISTICS OF MARINE WATERS IN THE CALCULATIONS OF HYDROLOGICAL FIELDS CLIMATIC CHANGES IN THE SURFACE LAYER OF THE BLACK SEA
V.A. Sokolov 1, S.P. Apuhtina 1, K.V. Pokazeev 2
1 N.N. Zubov State Oceanographic Institute, 119034, Moscow, Kropotkinskiy per., 6
2 M.V. Lomonosov Moscow State University, Faculty of Physics, 119991, Moscow, Leninskie gory, 1

Abstract. Based on the results of the analysis of climate histograms of joint probability density functions of seawater temperature T and salinity S, coupled with the analysis of the climate array of T-S diagrams, a statistical description of marine water masses and their properties is given, complementing the definition of these marine waters structures introduced by S.D. Dobrovolsky (1961). A relation is found between the presence of several water masses in the areas of marine research and the multi-modality of joint statistical distributions of the marine waters temperature T and salinity S fields. It is shown that the neglect of climate variability of water mass statistics in the calculations of surface water temperature in the Black sea led to a lack of response to Global climate warming, noted in the results of other independent empirical studies of the sea surface in this region. Taking into account the climate changes in marine water statistics, the response to Global warming in the surface layer of the Black Sea is identified in the studied fields.
Keywords: statistical properties of marine hydrological fields, water masses, verification of calculated values of hydrological fields.

PLASTIC PROPERTIES INFLUENCE ON HYDRAULIC FRACTURING OPERATION
M.A. Trimonova, I.O. Faskheev
M.A. Sadovsky Institute of Geosphere Dynamics of RAS, 119334, Russia, Moscow, Leninsky ave. 38-1

Abstract. Laboratory experiments on hydraulic fracturing (HFD) on model samples conducted in the M.A. Sadovsky Institute of Geosphere Dynamics of Russian Academy of Sciences (IGD RAS) have shown that classical elastic models cannot accurately predict the values of the fracture pressure. To study the mechanical elastic-plastic properties of samples, a series of experiments are done inSchmidt Institute of Physics of the Earth of the Russian Academy of Sciences (IPE RAS). According to the obtained data, authors of the presented work constructed numerical models using the Abaqus Student Edition software package. The geometry of the calculated area, applied boundary conditions, and elastic-plastic properties were set based on the conditions of hydraulic fracturing experiments and the results of uniaxial compression experiments. As a result of modeling, it is found that the pressurized rupture fluid causes plastic deformations in the vicinity of the well, which, in turn, is the cause of increased rupture pressure.
Keywords: hydraulic fracturing, plasticity, stresses, strains, experimental facility.

SIMULATION OF DEPTH REGIME IN THE SEA USING FIELD DATA ON THE VOLUME SCATTERING FUNCTION
E.B. Shybanov
Marine Hydrophysical Institute of RAS, 299011, Sevastopol, Kapitanskaya str. 2

Abstract. The aim of the work is to refine existing algorithms for experimental data processing on measurements of optical characteristics of sea water. The problem when the light field does not depend on lighting conditions is analyzed to find out features of multiple light scattering in a medium with a strong scattering anisotropy. For real scattering phase functions a simple iterative algorithm is proposed determining the characteristics of deep body brightness. The scattering indicatrix obtained during ship measurements in the Black sea in 2012 is used, device that measures the angular light scattering index in the angular range of 0.5–178 in 12 spectral ranges from 380 to 780 nm have been used on-board. In the calculations, the parameter of the indicatrix asymmetry varied from 25 to 72. It is shown that the error in determining the light absorption index based on the characteristics of the light field, due to inaccurate information about the scattering indicatrix, is significantly less than the error of such estimates made by the formulas of the two-stream approximation of the radiation transfer equation.
Keywords: light fields in Sea, depth regime, phase function, photon life probability, two-flux approximation, radiation transport.