Salinity and water effect on electrical properties of fragile clayey sandstone

Applied Water Science

Mohamed Mahmoud Gomaa¹ 

[1] Geophysical Sciences Department, National Research Centre;

关键词: Electrical conductivity;    Dielectric constant;    Complex impedance;    Saturation;    Loose clayey sandstone;    Frequency domain;   

DOI  :  10.1007/s13201-020-01189-0

来源: DOAJ

【 摘 要 】

Abstract There are enormous variations in the electrical characteristics of rocks and minerals according to many factors. Electrical measurements were taken to define the weight of these variations. Water saturation effect (partially and fully) on electrical characteristics of loose clayey sandstone samples was studied. Measurements were taken at room temperature (~ 19 °C) and a frequency range of (0.0005 Hz–100 kHz). Changes in water content are the only factor that controls changes in electrical properties. Change in frequency with water content is an important factor for electrical properties. At relatively low frequencies and low saturations, an interface between grains (charge accumulation at grain surfaces and bound water) is the dominating factor. Also, the bulk material properties at high frequency and full saturations are the controlling factors. At moderate saturations, there are surface charge displacement and exchange of excess ions between grains. For high saturations, due to existence of high mobilities of excess ions, the diffusion or membrane polarization is the main controlling mechanisms. The water used in the sample is 4 g of NaCl/100 g of distilled water. The electrical conductivity of the samples increases gradually with the addition of saline water. With an increase in frequency, variations of conductivity may be negligible.

【 授权许可】

Unknown