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Sadovenko I.,National Mining University | Rudakov D.,National Mining University | Podvigina O.,Ukrainian State Geological Prospecting Institute
New Techniques and Technologies in Mining - Proceedings of the School of Underground Mining | Year: 2010

The paper presents the results of studies concerning changes of hydrogeodynamics in the region of Central Donbass (Ukraine). The active mines are expected to be closed within the next twenty years, which requires predictive estimations for hydrogeodynamic trends in mined out strata. The studies were performed by numerical modeling of regional ground water flow. The model allowed reproducing paleohydrogeological conditions during pre-mining time, which is highly important to assess the impacts of the exploitation period. The predictive parametrical estimations were analyzed for different scenarios of mine closure. The proposed technical schemes include local draining and grouping of mine drainage; they aim eventually at self-draining of the post-mining region. © 2010 Taylor & Francis Group, London.


Kondrat'ev S.I.,Ukrainian Academy of Sciences | Prusov A.V.,Ukrainian Academy of Sciences | Yurovskii Y.G.,Ukrainian State Geological Prospecting Institute
Physical Oceanography | Year: 2010

We analyze the results of the field hydrological and hydrochemical observations of the submarine discharge of underground waters near the cape Aiya (South Coast of the Crimea) obtained with the help of the measuring equipment developed at the Marine Hydrophysical Institute of the Ukrainian National Academy of Sciences. We measure the current velocities, temperature, salinity, and the contents of silicic acid and phosphates inside a karst cavity and in the test region around the cavity. We present three estimates of the output of submarine discharge and compute the amounts of silicic acid and phosphates carried out into the sea by the submarine source. © 2010 Springer Science+Business Media, Inc.


Kryvoscheyev V.T.,Ukrainian State Geological Prospecting Institute | Kukuruza V.D.,NDRnaftogas | Ivanova Y.Z.,Ukrainian State Geological Prospecting Institute | Makogon V.V.,Ukrainian State Geological Prospecting Institute
Geoinformatics 2012 - 11th International Conference on Geoinformatics: Theoretical and Applied Aspects | Year: 2012

The estimations of resources of shale gas of Ukraine (as well as the world) strongly differ on different authors. Many researchers believe that we have much enough shale gas, to begin a scale production. This question requires the detailed study on a prospect. The reserves of traditional gas in Ukraine are mastered only 25%. We believe that today this gas to produce economically profitable and environmentally safer. Should be soon widely expand exploration work for discovery and development of new oil and gas deposits. With the active use of our reserves we quickly and significantly reduce the dependence on external supplies of hydrocarbon raw materials.


Tyapkin Y.,Ukrainian State Geological Prospecting Institute | Ursin B.,Norwegian University of Science and Technology | Perroud H.,University of Pau and Pays de l'Adour | Silinska O.,Ukrainian State Geological Prospecting Institute | Tiapkina O.,Norwegian University of Science and Technology
Journal of Geophysics and Engineering | Year: 2010

We have proposed a new least-squares method for signal estimation with a complicated and therefore more realistic mathematical model of the multichannel seismic record containing random noise and an arbitrary number of coherent noise wavetrains. The signal and all the coherent noise wavetrains are supposed to bear individual trace-independent waveforms being mutually uncorrelated in time stationary stochastic processes. The amplitudes and arrival times of these record components vary from trace to trace in an arbitrary manner. Random noise is assumed to be a stationary stochastic process uncorrelated with the signal and all the coherent noise wavetrains and from trace to trace as well. Its spectral (autocorrelation) function is trace independent to within a scale factor, the variance. Under certain conditions, the method may be reduced to two successive stages, namely preliminary subtraction of estimates of all the coherent noise wavetrains and final estimation of the signal from the residual record. At both stages, optimum weighted stacking is used with reference to the variances of random noise and to the amplitudes and arrival times of the corresponding coherent component. A simplified scheme and an advanced scheme for subtracting coherent noise are proposed, which are called the zero-order and first-order approximations, respectively. The first scheme can be thought of as the generalization of a conventional approach for subtracting coherent noise to the complicated data model adopted in this paper. The second scheme has an obvious advantage over the first scheme, since it allows the distortions that appear when estimating and subsequently subtracting the coherent noise wavetrains to be compensated. A simulation on synthetic data shows the efficiency of the first-order approximation, and it provides a qualitative and quantitative comparison of those results with the results given by the zero-order approximation. Also, testing the zero-order approximation exploiting the singular value decomposition on synthetic and actual data sets demonstrates the advantage of this method over f-k filtering combined with subsequent straight stacking. © 2010 Nanjing Institute of Geophysical Prospecting.


Roganov Y.,Ukrainian State Geological Prospecting Institute | Stovas A.,Norwegian University of Science and Technology
Geophysical Prospecting | Year: 2010

The presence of triplications (caustics) can be a serious problem in seismic data processing and analysis. The traveltime curve becomes multi-valued and the geometrical spreading correction factor tends to zero due to energy focusing.We analyse the conditions for the qSV-wave triplications in a homogeneous transversely isotropic medium with vertical symmetry axis. The proposed technique can easily be extended to the case of horizontally layered vertical symmetry axis medium. We show that the triplications of the qSV-wave in a multilayered medium imply certain algebra. We illustrate this algebra on a two-layer vertical symmetry axis model. © 2009 European Association of Geoscientists & Engineers.


Marmalevskyi N.,Ukrainian State Geological Prospecting Institute | Khromova I.,Lukoil | Kostyukevych A.,Tesseral Technologies Inc.
4th International Conference and Exhibition: New Discoveries through Integration of Geosciences, Saint Petersburg 2010 | Year: 2010

We consider a modification of duplex wave migration that enables seismic images of subvertical boundaries formed by waves of fixed incident angles to be obtained. This allows us to conduct AVO analysis of the subvertical boundaries for classification of faults and estimation of their properties. The role of a full-wave modeling for corrections required to obtain undistorted AVO curves is demonstrated.


Marmalevskyi N.,Ukrainian State Geological Prospecting Institute | Roganov Y.,Ukrainian State Geological Prospecting Institute | Gornyak Z.,Ukrainian State Geological Prospecting Institute | Kostyukevych A.,Tetrale Technologies Inc. | And 2 more authors.
72nd European Association of Geoscientists and Engineers Conference and Exhibition 2010: A New Spring for Geoscience. Incorporating SPE EUROPEC 2010 | Year: 2010

With synthetic examples, a method for evaluating vertical velocity and Thomsen's anisotropic parameters and in isotropic and vertical transverse isotropic (VTI) media is demonstrated. The method uses duplex wave migration (DWM) as the engine that determines these parameters. One of the characteristics of DWM based velocity analysis is that it's resolving power increases (rather than decreases) with depth. With DWM, seismic images of vertical boundaries in a narrow range of transformation apertures are formed. It allows group velocities in VTI media to be determined with a rather high accuracy. With these velocities, Thomsen parameters and vertical velocities are evaluated. The area in which the above parameters are determined is much smaller than for conventional PSDM based velocity analysis using sub-horizontal boundaries. Therefore, this method enables improved resolution of local lateral changes in anisotropic velocity parameters. © 2010, European Association of Geoscientists and Engineers.


Roganov Y.V.,Ukrainian State Geological Prospecting Institute | Stovas A.,Norwegian University of Science and Technology
72nd European Association of Geoscientists and Engineers Conference and Exhibition 2010: A New Spring for Geoscience. Incorporating SPE EUROPEC 2010 | Year: 2010

We consider the monochromatic wave propagation in a periodically layered transversely isotropic medium with vertical symmetry axis. We show that there are discontinuities on the qP- and qSV-wave slowness surface associated with corresponding stop-bands. The limited branches of the slowness surface result the special type of caustics in the group domain. © 2010, European Association of Geoscientists and Engineers.


Tiapkina O.,Norwegian University of Science and Technology | Landro M.,Norwegian University of Science and Technology | Tyapkin Y.,Ukrainian State Geological Prospecting Institute | Link B.,Tetrale Technologies
Geophysics | Year: 2012

The advent of single receiver point, multi-component geophones has necessitated that ground roll be removed in the processing flow rather than through acquisition design. A wide class of processing methods for ground-roll elimination is polarization filtering. A number of these methods use singular value decomposition (SVD) or some related transformations. We focus on a single-station SVD-based polarization filter that we consider to be one of the best in the industry. The method is comprised of two stages: (1) ground-roll detection and (2) ground-roll estimation and filtering. To detect the ground roll, a special attribute dependent on the singular values of a three-column matrix formed by a sliding time window is used. The ground roll is approximated and subtracted using the first two eigenimages of this matrix. To limit the possible damage to the signal, the filter operates within the record intervals where the ground roll is detected and within the ground-roll frequency bandwidth only. We improve the ground-roll detector to make it theoretically insensitive to ambient noise and more sensitive to the presence of ground roll. The advantage of the new detector is demonstrated on synthetic and field data sets. We estimate theoretically and with synthetic data the attenuation of the underlying reflections that can be caused by the polarization filter. We show that the underlying signal always loses almost all the energy on the vertical component and on the horizontal component in the ground-roll propagation plane and within the ground-roll frequency bandwidth. The only signal component, if it exists, that can retain a significant part of its energy is the horizontal component orthogonal to the above plane. When 2D 3C field operations are conducted, the signal particle motion can deviate from the ground-roll propagation plane and can therefore retain some of its energy due to a set of offline reflections. In the case of 3D 3C seismic surveys, the reflected signal always deviates from the ground-roll propagation plane on the receiver lines that do not contain the source. This is confirmed with a 2.5D 3C synthetic data set. We discuss when the ability of the filter to effectively subtract the ground roll may, or may not, allow us to ignore the inevitable harm that is done to the underlying reflected waves. © 2012 Society of Exploration Geophysicists.


Khromova I.,Lukoil | Link B.,Tetrale Technologies | Marmelevskyi N.,Ukrainian State Geological Prospecting Institute
First Break | Year: 2011

There are several methods based on seismic reflection data for locating natural fracture systems and predicting their permeability. The only practical way to compare the predictive accuracy of each method is to evaluate the results from different oilfields using data from several wells in each field. We have studied methods based on reflection amplitude, reflection curvature and its derivatives, coherency cube, spectral decomposition, ant tracking technology, azimuthal anisotropy of P-wave velocity, and duplex wave migration (DWM) amplitude cube analysis. Here we report and analyse the results of each method for carbonate fracture plays. The study involved the analysis of several 3D data volumes from two different areas using results from hundreds of wells which have been drilled over the last three decades. We conclude that the DWM technique is the most reliable method for fracture permeability prediction. Lukoil planned a 2010 drilling programme for horizontal wells based on this DWM technology, and the first exploration results show that the locations of fracture systems were predicted with an accuracy of 25 m. © 2011 EAGE www.firstbreak.org.

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