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Frequency-Dependent Electrical Characterization of Rock Types from Ewekoro, Eastern Dahomey Basin, Nigeria


Affiliations
1 Department of Physics, University of Lagos, Lagos, Nigeria
2 CSIRO Earth Science and Resource Engineering, 26 Dick Perry Ave, Kensington, Western Australia 6151, Australia
 

Dielectric measurements (40 Hz-110 MHz) conducted on samples of limestone and its associated rocks from Ewekoro, Eastern Dahomey Basin, Nigeria has yielded vital information for characterization. Cole-Cole plots manifest a distribution of relaxation times in the rock samples common for multicomponent systems. All the rock types show dielectric dispersion in dry and partially saturated conditions, but the frequency range differs for the rock types and depends on wettability. At partial water saturation there is: (i) enhanced polarization resulting in increase in real and imaginary permittivities; (ii) shortened region of dielectric dispersion; (iii) broadened electrode polarization plateau; and (iv) steeper and shorter dispersion region. Irrespective of the state of the rocks, dielectric parameters for shale and glauconite are at least an order greater than for limestone and sandstone. Geometric or textural effects are partly responsible for the observed differences coupled with the presence of charged clay/clay-like particles in shale and glauconite. Decrease in relaxation and critical frequencies in partial saturation for shale in contrast to the increase in these frequencies for the other three rock types is due the effect of pore geometry on overall dielectric relaxation. This study shows that dielectric measurement can complement geochemical analysis in laboratory evaluation and characterization of rock raw materials.

Keywords

Dielectric Dispersion, Frequency Response, Loss Tangent, Partial Saturation, Rock Types.
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  • Cook, N. J., Mineral characterization of industrial mineral deposits at the Geological Survey of Norway: a short introduction. NGU Bull., 2000, 436, 189–192.

  • Worrell, E., Galitsky, C. and Price, L., Energy efficiency improvement opportunities for the cement industry. Environmental Energy Technologies Division LBNL-72E, Berkeley National Laboratory, CA, USA, 2008.

  • Harrison, D. J., Industrial mineral laboratory manual – limestone. Technical Report WG/92/29, Mineralogy and Petrology Series, British Geological Survey, UK, 1993.

  • British Geological Survey, UK, Mineral Profile-Cement Raw Materials, 2005, p. 20.

  • van Straaten, P., Rocks for crops: agrominerals for Sub-Saharan Africa. ICRAF, Nairobi, Kenya, 2002, pp. 227–230.

  • Kogbe, C. A., The Cretacious and Paleocene sediments of southern Nigeria. In Geology of Nigeria (ed. Kogbe, C. A.), Abiprint and Pak Ltd, Ibadan, Nigeria, 1975, p. 436.

  • Schneider, H., A study of glauconite. J. Geol., 1927, 35(4), 289–310.

  • Aldieb, M. A. and Ibrahim, H. G., Variation of feed chemical composition and its effect on clinker formation–simulation process. In Proceedings of the World Congress on Engineering and Computer Science, San Francisco, USA, 20–22 October 2010, vol. 2.

  • Josh, M., Clennell, B. and Siggins, A. Practical broadband dielectric measurement of geological materials. In SPWLA 50th Annual Logging Symposium, Texas, USA, 21–24 June 2009.

  • Josh, M., Esteban, L., Delle Piane, C., Sarout, J., Dewhurst, D. N. and Clennell, M. B., Laboratory characterization of shale properties. J. Petr. Sci. Eng., 2012, 88, 107–124.

  • Knight, R. J., The dielectric constant of sandstones: 5 Hz to 13 MHz: Ph D thesis, Stanford University, USA, 1984.

  • Knight, R., The use of complex plane plots in studying the electrical response of rocks. J. Geomagn. Geoelectr., 1984, 35, 767–776.

  • Knight, R. J. and Nur, A., The dielectric constant of sandstones, 50 kHz to 4 MHz. Geophysics, 1987, 52, 644–654.

  • Knight, R. J. and Nur, A., Geometrical effects in the dielectrical response of partially saturated sandstones. Log Anal., 1987, 28, 513–519.

  • Garrouch, A. A. and Sharma, M. M., Dielectric dispersion of partially saturated porous media in the frequency range 10 Hz to 10 MHz. Log Anal., 1998, 39, 48–53.

  • Garrouch, A. A., A systematic study revealing resistivity dispersion in porous media. Log Anal., 1999, 40, 271–279.

  • Adisoemarta, P. S., Complex electrical properties of shale as a function of frequency and water content. Ph D thesis, Texas Tech University, Texas, USA, 1999.

  • Seleznev, N. V., Theoretical and laboratory investigation of dielectric properties of partially saturated carbonate rocks. Ph D thesis, TU Delft, The Netherlands, 2005.

  • Josh, M., Dielectric permittivity: a petrophysical parameter for shales. Petrophysics, 2014, 55(4), 319–332.

  • Knight, R. J. and Endres, A. L., A new concept in modeling the dielectrical response of sandstones: defining a wetted rock and bulk water system. Geophysics, 1990, 55, 586–594.

  • Garrouch, A. A. and Sharma, M. M., The influence of clay content, salinity, sress, and wettability on the dielectric properties of brine-saturated rocks: 10 Hz to 10 MHz. Geophysics, 1994, 59(6), 909–917.

  • Gomaa, M. M., Relation between electric properties and water saturation for hematitic sandstone with frequency. Ann. Geophys., 2008, 51(5/6), 801–811.

  • Toumelin, E., Torres-Verdin, C. and Bona, N., Improving the petrophysical assessment of rock-fluid systems with wide-band electromagnetic measurements. In Annual Technical Conference and Exhibition, Dallas, Texas, USA, SPE 96258, 9–12 October 2005.

  • Toumelin, E., Torres-Verdin, C. and Bona, N., Improving petrophysical interpretation with wide-band electromagnetic measurements. SPE J., 2008, 13(2), 205–215.

  • Chelidze, T. L. and Gueguen, Y., Electrical spectroscopy of porous rocks: a review – I. Theoretical models. Geophys. J. Int., 1999, 137, 1–15.

  • Chelidze, T. L., Gueguen, Y. and Ruffet, C., Electrical spectroscopy of porous rocks: a review – II. Experimental results and interpretation. Geophys. J. Int., 1999, 137, 16–34.

  • Bigakle, J., A study concerning the conductivity of porous rock. Phys. Chem. Earth, 2000, A25, 189–194.

  • Sengwa, R. J. and Soni, A., Dielectric properties of some minerals of western Rajasthan. Indian J. Radio Space Phys., 2008, 37, 57–63.

  • Knight, R. J. and Abad, A., Rock/water interaction in dielectric properties: experiments with hydrophobic sandstones. Geophys., 1995, 60(2), 431–436.

  • Fechner, T., Borner, F. D., Richter, T., Yaramanci, U. and Weihnacht, B., Lithological interpretation of the spectral properties of limestone. Near Surf. Geophys., 2004, 3, 150–159.

  • Bekhit, M. M. and Khalil, S. A., Electrical properties of moist limestone samples in the frequency range 1 Hz–10 MHz from Abu Rawash Area. Aust. J. Basic Appl. Sci., 2007, 1(4), 741–750.

  • Hu, K. and Liu, C. R., Theoretical study of the dielectric constant in porous sandstone saturated with hydrocarbon and water. IEEE Trans. Geosci. Remote Sensing, 2000, 38(3), 1328–1336.

  • Szerbiak, R. B., McMechan, G. A. Forster, C. and Snelgrove, S. H., Electrical and petrophysical modelling of Ferron sandstone. Geophysics, 2006, 71, 197–210.

  • Fam, M. A. and Dusseault, M. B., High-frequency complex permittivity of shales (0.02–1.30 GHz). Can. Geotech. J., 1998, 35(3), 524–531.

  • Sweeney, J., Roberts, J. and Harben, P., Study of dielectric properties of dry and saturated Green River oil shale. Energy Fuels, 2007, 21, 2769–2777.

  • Srodon, J., Drits, V. A., MCcarty, D. K., Hsieh, J. C. C. and Eberl, D. D., Quantitative X-ray diffraction analysis of clay-bearing rocks from random preparation. Clays Clay Miner., 2001, 49(6), 514–528.

  • Obiajunwa, E. I. and Nwachukwu, J. I., Elemental analysis of limestone samples from Ewekoro limestone deposit in southwest Nigeria. Nucl. Instrum. Meth. Phys. Res. B, 2000, 170, 427–431.

  • Cole, K. S. and Cole, R. H., Dispersion and absorption in dielectrics. J. Chem. Phys., 1941, 9, 341–351.

  • Debye, P., Ver. Deut. Phys. Gesell., 1913, 15, 777; reprinted in collected papers of Peter J. W. Debye, Interscience, New York, 1954.

  • Debye, P., Polar Molecules, Dover Publication, New York, USA, 1929.

  • Jonsher, A. K., Dielectric relaxation in solids. J. Phys. D: Appl. Phys., 1999, 32, R57–R70.

  • Olhoeft, G. R., Electrical properties of rocks. In Physical Properties of Rocks and Minerals (eds Touloukian, Y. S., Judd, W. R. and Roy, R. F.), McGraw-Hill, New York, 1976.

  • Sen, P. N., Relation of certain geometric features to the dielectric anomaly of rocks. Geophysics, 1981, 46, 1714–1720.

  • Sen, P. N. and Chew, W. C., The frequency dependent dielectric and conductivity response of sedimentary rocks. J. Microwave Power, 1983, 18(1), 95–105.

  • Chew, W. C. and Sen, P. N., Dielectric enhancement due to electrochemical double layer: thin double layer approximation. J. Chem. Phys., 1982, 77(9), 4683–4693.

  • Gruner, J. W., The structural relationship of glauconite and mica. J. Mineral. Soc. Am., 1935, 20, 699–714.

  • Jarrar, G., Amireh, B. and Zachmann, D., The major, trace and rare earth element geochemistry of glauconites from the early Cretaceous Kurnub Group of Jordan. Geochem. J., 2000, 34, 207–222.

  • Odin, G. S. and Matter, A., De glauconiarum origine. Sedimentology, 1981, 28, 611–641.

  • Odin, G. S., Green marine clays. In Development in Sedimentology, Amsterdam, Elsevier, 1988, p. 45.

  • Myers, M. T., A saturation interpretation model for the dielectric constant of shaly sands. SCA Conference Paper 9118, San Antonio, Texas, USA, August 1991.


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  • Frequency-Dependent Electrical Characterization of Rock Types from Ewekoro, Eastern Dahomey Basin, Nigeria

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Authors

O. B. Olatinsu
Department of Physics, University of Lagos, Lagos, Nigeria
D. O. Olorode
Department of Physics, University of Lagos, Lagos, Nigeria
M. Josh
CSIRO Earth Science and Resource Engineering, 26 Dick Perry Ave, Kensington, Western Australia 6151, Australia
B. Clennell
CSIRO Earth Science and Resource Engineering, 26 Dick Perry Ave, Kensington, Western Australia 6151, Australia
L. Esteban
CSIRO Earth Science and Resource Engineering, 26 Dick Perry Ave, Kensington, Western Australia 6151, Australia

Abstract


Dielectric measurements (40 Hz-110 MHz) conducted on samples of limestone and its associated rocks from Ewekoro, Eastern Dahomey Basin, Nigeria has yielded vital information for characterization. Cole-Cole plots manifest a distribution of relaxation times in the rock samples common for multicomponent systems. All the rock types show dielectric dispersion in dry and partially saturated conditions, but the frequency range differs for the rock types and depends on wettability. At partial water saturation there is: (i) enhanced polarization resulting in increase in real and imaginary permittivities; (ii) shortened region of dielectric dispersion; (iii) broadened electrode polarization plateau; and (iv) steeper and shorter dispersion region. Irrespective of the state of the rocks, dielectric parameters for shale and glauconite are at least an order greater than for limestone and sandstone. Geometric or textural effects are partly responsible for the observed differences coupled with the presence of charged clay/clay-like particles in shale and glauconite. Decrease in relaxation and critical frequencies in partial saturation for shale in contrast to the increase in these frequencies for the other three rock types is due the effect of pore geometry on overall dielectric relaxation. This study shows that dielectric measurement can complement geochemical analysis in laboratory evaluation and characterization of rock raw materials.

Keywords


Dielectric Dispersion, Frequency Response, Loss Tangent, Partial Saturation, Rock Types.

References





DOI: https://doi.org/10.18520/cs%2Fv113%2Fi02%2F253-263