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Michael S. Zhdanov - One of the best experts on this subject based on the ideXlab platform.

  • Direct Current and Induced Polarization Methods
    Foundations of Geophysical Electromagnetic Theory and Methods, 2018
    Co-Authors: Michael S. Zhdanov
    Abstract:

    This Chapter examines in detail the first class of electrical geophysical methods – the DC methods. While both electromagnetic and DC methods first came into use in the early part of the 20th century, the DC methods gained early acceptance because of less demanding theoretical and instrumentation considerations. DC methods have become the most widely used geoelectric method. We discuss three important groups of DC electric techniques including those known as vertical electric sounding (VES), horizontal profiling, and the electrical mapping methods. A highly important time-varying electrical method called Induced Polarization (IP) method is presented as well. In this method, it is recognized that the current flow in the earth represents a very complex EM phenomenon characterized by charge Polarization and accumulation in the rocks. Mathematically, the IP phenomena can be analyzed based on models with frequency-dependent complex conductivity distribution, e.g., a Cole-Cole model. We also consider a generalized effective-medium theory of Induced Polarization (GEMTIP) which was introduced recently in order to provide a link between the petrophysical properties of the rocks and their complex conductivity spectra

  • Experimental Study of Induced Polarization Effect in Unconventional Reservoir Rocks
    2014
    Co-Authors: Vladimir Burtman, Michael S. Zhdanov
    Abstract:

    Unconventional hydrocarbon reserves substantially surpass those of conventional resources and therefore are extremely economically attractive. However, exploration and production of uncon-ventional reserves is challenging. This paper demonstrates that one can observe significant Induced Polarization effects in shale reservoir rocks, which can be used in exploration for unconventional reserves. The generalized effective-medium theory of Induced Polarization (GEMTIP) was used to model the complex resistivity of shale rocks. We demonstrate that GEMTIP modeling provides an evaluation of mineral composition and volume fractions in rock samples. We have conducted spectral Induced Polarization (IP) measurements using different types of shale rocks to test the feasibility of the IP method and GEMTIP modeling for studying unconventional hydrocarbon (HC) reservoir rocks.

  • Spectral Induced Polarization effect in unconventional reservoir rocks
    Seg Technical Program Expanded Abstracts, 2014
    Co-Authors: Vladimir Burtman, Michael S. Zhdanov
    Abstract:

    Unconventional hydrocarbon (HC) reserves, e.g., heavy oils, bituminous sands, and oiland gas-shale substantially surpass those of conventional resources and therefore are extremely economically attractive; however, exploration and production of unconventional reserves is challenging. This paper demonstrates that one can observe significant Induced Polarization (IP) effects in shale reservoir rocks, which can be used in exploration for unconventional reserves. This study is based on application of the generalized effective-medium theory of Induced Polarization (GEMTIP) for analysis of the complex resistivity (CR) of oiland gas-shale rocks. GEMTIP modeling provides a basis for remote petrophysical analysis of shale rocks, which we compared with an actual structural analysis of shale rocks using Quantitative Evaluation of Minerals by Scanning Electron Microscopy (QEMSCAN) and core analysis. We demonstrate that GEMTIP modeling provides an evaluation of mineral composition and volume fractions in rock samples. Spectral Induced Polarization (SIP) measurements were conducted for different types of shale rocks to test the feasibility of the SIP method and GEMTIP modeling for studying unconventional HC reserves. The results of this study provide a basis for future application of the SIP method for exploration and monitoring of unconventional reserves.

  • generalized effective medium theory of Induced Polarization
    Geophysics, 2008
    Co-Authors: Michael S. Zhdanov
    Abstract:

    A rigorous physical-mathematical model of heterogeneous conductive media is based on the effective-medium approach. A generalization of the classical effective-medium theory (EMT) consists of two major parts: (1) introduction of effective-conductivity models of heterogeneous, multiphase rock formations with inclusions of arbitrary shape and conductivity using the principles of the quasi-linear (QL) approximation within the framework of the EMT formalism and (2) development of the generalized effective-medium theory of Induced Polarization (GEMTIP), which takes into account electromagnetic-induction (EMI) and Induced Polarization (IP) effects related to the relaxation of polarized charges in rock formations. The new generalized EMT provides a unified mathematical model of heterogeneity, multiphase structure, and the polarizability of rocks. The geoelectric parameters of this model are determined by the intrinsic petrophysical and geometric characteristics of composite media: the mineralization and/or fluid content of rocks and the matrix composition, porosity, anisotropy, and polarizability of formations. The GEMTIP model allows one to find the effective conductivity of a medium with inclusions that have arbitrary shape and electrical properties. One fundamental IP model of an isotropic, multiphase, heterogeneous medium is filled with spherical inclusions. This model, because of its relative simplicity, makes it possible to explain the close relationships between the new GEMTIP conductivity-relaxation model and an empirical Cole-Cole model or classical Wait's model of the IP effect.

André Revil - One of the best experts on this subject based on the ideXlab platform.

  • Induced Polarization as a tool to characterize shallow landslides
    Journal of Hydrology, 2020
    Co-Authors: André Revil, A. Soueid Ahmed, A. Coperey, Ludovic Ravanel, Rajesh Sharma, Ns Panwar
    Abstract:

    Abstract The development of shallow landslides is strongly connected to the changes in the water content of soils on hillslopes, their clay content and permeability distribution, which, in turn, are playing an important role regarding their hydro-mechanical properties. A non-intrusive geophysical method able to map these properties would be very helpful. The most common geoelectrical method, DC (Direct Current) resistivity, cannot be used as a stand-alone technique for this purpose since it depends on two contributions (bulk and surface conductivities), which depend on the water content and the cation exchange capacity (CEC) of the material. Induced Polarization is a geophysical method that can be now used to complement DC resistivity in providing key material properties that can be used to diagnose potential risks for failure. We first recall the basic principles behind the Induced Polarization method from laboratory to field scales and key findings in the underlying petrophysics needed to jointly interpret electrical conductivity and normalized chargeability tomograms. Then, we apply these relationships to a field survey carried out over a shallow landslide at Claix (Isere, France), close to Grenoble. A 3D Induced Polarization survey was carried out and interpreted in terms of the clay content, water content, and permeability distributions. We demonstrate that the landslide is associated with a channel of high water content corresponding with the presence of travertine, a flow-path, and a permeability barrier downslope corresponding to the presence of plastic clays. This study demonstrates that Induced Polarization can be used to characterize the impacted volume and therefore might have been useful to map the area before the landslide to assess the possible risk of failure. This methodology could play a key role in mitigation planning.

  • Induced Polarization as a tool to non-intrusively characterize embankment hydraulic properties
    Engineering Geology, 2020
    Co-Authors: A. Soueid Ahmed, André Revil, F. Abdulsamad, B. Steck, C. Vergniault, V. Guihard
    Abstract:

    Abstract Characterizing key petrophysical parameters of dams and embankments (including water content, specific surface area or cation exchange exchange capacity, and permeability) is an important task in estimating their degree of safety. So far, Induced Polarization tomography has not been investigated to check if it can play such a role. We have conducted a time domain Induced Polarization profile along the embankment of a canal in the South East of France. The profile is 560 m long. It comprises 1696 apparent resistivity and chargeability data and was accomplished by separating the current and voltage electrode cables to improve the signal-to-noise ratio. In order to complement the study, we performed Induced Polarization measurements on six core samples (including a clayey material and five carbonate rocks) collected from outcrops. A petrophysical Induced Polarization model called the dynamic Stern layer model is tested to see how the electrical conductivity and the normalized chargeability can be both connected to the porosity, the cation exchange capacity (CEC), and permeability of these materials. Then, these results are applied to interpret the electrical conductivity and normalized chargeability tomograms into water content and CEC tomograms. In turn, these two parameters are used to compute a permeability index.

  • Multiscale Induced Polarization tomography in hydrogeophysics: A new approach
    Advances in Water Resources, 2019
    Co-Authors: A. Soueid Ahmed, André Revil, Lutz Gross
    Abstract:

    Abstract Induced Polarization is a geophysical method that has gained ground in the last decade in hydrogeophysics. Yet the acquisition of high quality Induced Polarization data may be challenging using the current technologies mostly because of capacitive coupling effects especially for short durations in the injected current. In addition, making a true 3D Induced Polarization survey is very tedious and time consuming in field conditions. We discuss the advantages of a new generation of Induced Polarization equipment composed of individual stations able to measure the two components of the electric field along the ground surface. We show how this approach allows for integrating the whole data avoiding negative apparent resistivity/chargeability data. The use of decentralized recording stations solves the issue of capacitive coupling effects. We present a completely novel Induced Polarization data inversion methodology based on the measurement of the electric field components. In addition, a robust geostatistical inversion approach is discussed for recovering the conductivity and chargeability fields using the electric field components measured on the ground surface. We also treat the case of time lapse monitoring by using a low-rank Kalman filter approximation, which is computationally very appealing in terms of computational time and storage savings. The effectiveness of the new methodology is demonstrated on several realistic synthetic case studies. These numerical tests show that this electric field-based approach is robust and very promising for applications in hydrogeophysics.

  • Spectral Induced Polarization porosimetry
    Geophysical Journal International, 2014
    Co-Authors: André Revil, Nicolas Florsch, Christian Camerlynck
    Abstract:

    Induced Polarization is a geophysical method looking to image and interpret low-frequency Polarization mechanisms occurring in porous media. Below 10 kHz, the quadrature conductivity of metal-free sandy and clayey materials exhibits a distribution of relaxation times, which can be related to the pore size distribution of these porous materials. When the Polarization spectra are fitted with a Cole-Cole model, we first observe that the main relaxation time is controlled by the main pore size of the material and that the Cole-Cole exponent c is never much above 0.5, a value corresponding to a Warburg function. The complex conductivity is then obtained through a convolution product between the pore size distribution and such Warburg function. We also provide a way to recover the pore size distribution by performing a deconvolution of measured spectra using the Warburg function. A new dataset of mercury porosimetry and Induced Polarization data of six siliciclastic materials supports the hypothesis that the Cole-Cole relaxation time is strongly controlled by the pore size, and especially the characteristic pore size corresponding to the peak of the pore size distribution from mercury porosimetry. The distribution of the pore throat sizes of these materials seems fairly well recovered using the Warburg decomposition of the spectral Induced Polarization spectra but additional data will be needed to confirm this finding.

  • HOW USEFUL IS SPECTRAL Induced Polarization
    23rd EEGS Symposium on the Application of Geophysics to Engineering and Environmental Problems, 2012
    Co-Authors: André Revil
    Abstract:

    Induced Polarization represents the accumulation of charge carriers (electrons and ions) in a porous material and their back-diffusion in their concentration fields. This geophysical method can be carried out either in the time domain or in the frequency domain. In principle frequency domain Induced Polarization (SIP) may offer a powerful geophysical method to solve a number of hydrogeochemical problems including imaging permeability distribution and a reconnaissance tool for contaminant plumes. In practice, this method is limited by a number of issues including electromagnetic coupling above 100 Hz, the mutiplicity of Polarization contributions that make the interpretation delicate, flat spectra that are poorly informative in systems characterized by a broad distribution of relaxation times, the long duration needed to take a snap-shot and so on. Therefore it is legitimate to wonder under what conditions spectral Induced Polarization is a powerful method, ... or not.

Tao Chen - One of the best experts on this subject based on the ideXlab platform.

  • Properties of Induced Polarization evanescent reflection with a solid immersion lens (SIL)
    Optics Express, 2007
    Co-Authors: Tao Chen, Thomas D Milster
    Abstract:

    Properties of the Induced Polarization signal with a solid immersion lens (SIL) are investigated by experiments and simulations. A LaSFN9 SIL (NA=1.5) is used in the experiment. Physics of the Induced Polarization signal are described for several configurations of optical systems and substrates. Induced Polarization signals from evanescent-wave coupling to dielectric, semiconductor and metal substrates are studied in detail. It is shown that surface plasmon waves are excited with Au substrates and the Induced Polarization signal is affected by the surface plasmon waves. Simulation results of the Induced Polarization signal for a gallium phosphide SIL (NA=2.64) are discussed.

  • Evanescent imaging with Induced Polarization by using a solid immersion lens
    Optics Letters, 2006
    Co-Authors: Tao Chen, Thomas D Milster, Seung Hune Yang, Delbert Hansen
    Abstract:

    Image contrast enhancement, high lateral resolution, and height information are obtained with Induced Polarization evanescent imaging using a solid immersion lens. Experiments are conducted by imaging features on a patterned Si substrate. Imaging theory is used to predict optimum orientation of high-spatial-frequency samples, and a topographical image is derived from the Induced Polarization image through a calibration procedure. A numerical aperture of 1.5 is used in the experiment. Height accuracy of +/-2 nm is demonstrated with a known sample.

  • Near-Field Induced Polarization Imaging for Optical Data Storage Metrology
    2006 Optical Data Storage Topical Meeting, 2006
    Co-Authors: Tao Chen, T.d. Milster
    Abstract:

    It is shown that when the Induced Polarization is used to acquire near-field Induced Polarization images, both a high-resolution near-field image and height information of the object are obtained

  • Semiconductor pattern analysis with Induced Polarization
    25th Annual BACUS Symposium on Photomask Technology, 2005
    Co-Authors: Tao Chen, Thomas D Milster, Seung Hune Yang
    Abstract:

    Image contrast enhancement, resolution improvement and accurate height information are obtained by near-field Induced Polarization imaging using a solid immersion lens (SIL) microscopy. A semiconductor PC processor is investigated by this imaging technology. With 520nm linear Polarization illumination, around 100nm feature size is resolvable, and topographical information is also achieved from this Induced Polarization image. We demonstrate this near-field Induced Polarization imaging is a fast acquisition, large field and high resolution metrology solution.

Thomas D Milster - One of the best experts on this subject based on the ideXlab platform.

  • Properties of Induced Polarization evanescent reflection with a solid immersion lens (SIL)
    Optics Express, 2007
    Co-Authors: Tao Chen, Thomas D Milster
    Abstract:

    Properties of the Induced Polarization signal with a solid immersion lens (SIL) are investigated by experiments and simulations. A LaSFN9 SIL (NA=1.5) is used in the experiment. Physics of the Induced Polarization signal are described for several configurations of optical systems and substrates. Induced Polarization signals from evanescent-wave coupling to dielectric, semiconductor and metal substrates are studied in detail. It is shown that surface plasmon waves are excited with Au substrates and the Induced Polarization signal is affected by the surface plasmon waves. Simulation results of the Induced Polarization signal for a gallium phosphide SIL (NA=2.64) are discussed.

  • Evanescent imaging with Induced Polarization by using a solid immersion lens
    Optics Letters, 2006
    Co-Authors: Tao Chen, Thomas D Milster, Seung Hune Yang, Delbert Hansen
    Abstract:

    Image contrast enhancement, high lateral resolution, and height information are obtained with Induced Polarization evanescent imaging using a solid immersion lens. Experiments are conducted by imaging features on a patterned Si substrate. Imaging theory is used to predict optimum orientation of high-spatial-frequency samples, and a topographical image is derived from the Induced Polarization image through a calibration procedure. A numerical aperture of 1.5 is used in the experiment. Height accuracy of +/-2 nm is demonstrated with a known sample.

  • Semiconductor pattern analysis with Induced Polarization
    25th Annual BACUS Symposium on Photomask Technology, 2005
    Co-Authors: Tao Chen, Thomas D Milster, Seung Hune Yang
    Abstract:

    Image contrast enhancement, resolution improvement and accurate height information are obtained by near-field Induced Polarization imaging using a solid immersion lens (SIL) microscopy. A semiconductor PC processor is investigated by this imaging technology. With 520nm linear Polarization illumination, around 100nm feature size is resolvable, and topographical information is also achieved from this Induced Polarization image. We demonstrate this near-field Induced Polarization imaging is a fast acquisition, large field and high resolution metrology solution.

Tong Maosong - One of the best experts on this subject based on the ideXlab platform.

  • Estimation of permeability of shaly sand reservoir from Induced Polarization relaxation time spectra
    Journal of Petroleum Science and Engineering, 2004
    Co-Authors: Tong Maosong, Wang Wei-nan, Jiang Yi-zhong, Shi Deqin
    Abstract:

    Abstract The Induced Polarization (IP) decay curve contains more information than the polarizability which was used in the conventional Induced Polarization logging tool. The Singular Value Decomposition (SVD) method makes it possible to transform Induced Polarization decay data into relaxation time spectra. The appropriate number of relaxation arrangement points in relaxation data inversion ranges from 32 to 64. The Induced Polarization relaxation time spectrum can be used to quantitatively estimate the pore size distribution of the shaly sands saturated with the NaCl brine. Combining the average IP relaxation time constant with the porosity can markedly improve the accuracy of determining the permeability over using total porosity from core measurements.

  • Research on determining permeability with Induced Polarization relaxation spectra
    Journal of Jiling University, 2004
    Co-Authors: Tong Maosong, Wang Wei-nan, Jiang Yi-zhong, Fan Qing-hua, Wang Rong, Du Guo-tong
    Abstract:

    Induced Polarization relaxation is a function of pore size. The singular value decomposition algorithm is used to inverse the Induced Polarization multi-relaxation data of rock samples. The relaxation spectrum is smoothly and shows a multi-peak shape. The influence of electrolytes on the spectra results from difference of diffusion constants. Spectra shift left with increasing the constant. In addition, the relationship between relaxation spectra and permeability is also investigated by combining the core porosity, permeability and formation factor. The results show that IP relaxation related to the reservoir permeability logK has linear relationship to log(T~(1/2 )_g/ F) and log(T_(g) /F).