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

Document Type : Research Article

Author

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

Abstract

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.

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References

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Journal of the Earth and Space Physics
Volume 46, Issue 4
February 2021
Pages 13-26

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