Using Electrical Properties of Some Subsurface Sedimentary Rocks as a Tool to Detect Bedding Direction

نوع مقاله : مقاله پژوهشی

نویسنده

Professor, Department of Geophysical Sciences, National Research Center, Cairo, Egypt

چکیده

The direction of bedding is not natural to be detected using laboratory measurements. Cretaceous rocks are mainly composed of sandstone and clay (clastic facies, sandstones, siltstones, mudstone). Electrical characteristics were measured perpendicular and parallel to layer direction (42 Hz to 5 MHz) to detect anisotropy and homogeneity of samples. Electrical characteristics of samples were measured at the dry state and three different salines (NaCl) concentrations at a constant temperature. Electrical anisotropy and homogeneity of samples are contributed mainly to load pressure direction compaction. Previous factors are an excellent diagenetic feature and changes from one example to another. Elongation of conductor and insulator grains will change electrical properties. Due to the homogeneity of samples, the only variable in electrical characteristics will relate to the anisotropy of grains. When the grains are, more or less, spherical, then electrical components will be similar at two perpendicular directions. Whereas, when grains are needles or disks, later, electrical characteristics will be changed. This paper tries to detect qualitatively and as a quick tool, anisotropy and homogeneity of samples by measuring their electrical properties. Anisotropy in studied samples was described by slight to moderate electric lineation and foliation.

کلیدواژه‌ها

موضوعات

عنوان مقاله [English]

Using Electrical Properties of Some Subsurface Sedimentary Rocks as a Tool to Detect Bedding Direction

نویسنده [English]

  • Mohamed M. Gomaa
Professor, Department of Geophysical Sciences, National Research Center, Cairo, Egypt
چکیده [English]

The direction of bedding is not natural to be detected using laboratory measurements. Cretaceous rocks are mainly composed of sandstone and clay (clastic facies, sandstones, siltstones, mudstone). Electrical characteristics were measured perpendicular and parallel to layer direction (42 Hz to 5 MHz) to detect anisotropy and homogeneity of samples. Electrical characteristics of samples were measured at the dry state and three different salines (NaCl) concentrations at a constant temperature. Electrical anisotropy and homogeneity of samples are contributed mainly to load pressure direction compaction. Previous factors are an excellent diagenetic feature and changes from one example to another. Elongation of conductor and insulator grains will change electrical properties. Due to the homogeneity of samples, the only variable in electrical characteristics will relate to the anisotropy of grains. When the grains are, more or less, spherical, then electrical components will be similar at two perpendicular directions. Whereas, when grains are needles or disks, later, electrical characteristics will be changed. This paper tries to detect qualitatively and as a quick tool, anisotropy and homogeneity of samples by measuring their electrical properties. Anisotropy in studied samples was described by slight to moderate electric lineation and foliation.

کلیدواژه‌ها [English]

  • Electric
  • Dielectric constant
  • Complex conductivity
  • Clastic
  • Anisotropy
  • Heterogeneity

مراجع

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Gomaa, M.M., Abou El-Anwar, E., 2015, Electrical and geochemical properties of tufa deposits as related to mineral composition in South Western Desert, Egypt. Journal of Geophysics and Engineering, 12(3), 292-302.
Gomaa, M.M. and Abou El-Anwar, E., 2017, Electrical, mineralogical, and geochemical properties of Um Gheig and Um Bogma Formations, Egypt. Carbonates and Evaporites, 1-14, https://doi.org/10.1007/s13146-017-0370-5.
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فیزیک زمین و فضا
دوره 46، شماره 4
بهمن 1399
صفحه 13-26

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