Avances en la investigación en ciencias aplicadas Acceso abierto

Abstracto

Radio frequency dielectric properties of limestone and sandstone from Ewekoro, Eastern Dahomey Basin

Olatinsu O. B., Olorode D. O. and Oyedele K. F.

The dielectric properties of nine rock samples [limestone (8) and sandstone (4)] collected from Ewekoro in Ogun State, Nigeria were studied in the range 10 kHz – 110 MHz under ambient atmospheric conditions. It is found that dielectric constant ( r e¢ ) values of the dry samples decreases with increase in frequency in the range of measurement. Dielectric dispersion is relatively large in almost all the samples. Conductivity dispersions followed the opposite trend increasing in values with increase in frequency. Peaks are more pronounced in loss tangent (D) curve than in dielectric loss ( r e¢ ) curve. This is an indication that overall electrical response of these samples is better revealed by loss tangent variation than dielectric loss variation. All the studied samples are governed by Cole-Cole dispersion which indicates a distribution of relaxation times which is common for multicomponent systems. This is confirmed by the value of the spread parameter which is below 0.5 for all the samples