The results of experimental measurements of the complex dielectric permittivity (CDP) of powders of quartz granules with different sizes saturated with water and salt solution of weak concentration are given in the frequency band from 20 kHz to 1 GHz. It is shown that at values of saturation level from 0.6 to 0.9 the relaxation phenomena caused by interfacial polarization on the water-air bound can be observed. The result shows considerable reduction of attenuation in gradually saturated rocks, which allows for deeper sensing during georadar mapping. It is determined that in the dielectric relaxation band and at frequencies below it the hysteresis of the real part of the CDP and equivalent specific conductivity can be observed. Its character significantly depends on the sizes of granules. It is shown that the behavior of CDP and attenuation of an electromagnetic wave at frequencies from 0.1 to 10 MHz complicatedly depends on the sizes of granules, saturation level, salinity of the saturating solution and saturation history.
Anastasiya Sergeevna Lapina,
Pavel Petrovich Bobrov,
"Electromagnetic Waves Attenuation in the Sandstones with Grains of Different Size at Imbibition and Drying," Progress In Electromagnetics Research M,
Vol. 45, 9-16, 2016. doi:10.2528/PIERM15072502
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