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Thermal properties are usually the key parameters governing the heat transfer through any material. Hence in modeling the thermal behavior of materials, accurate determination of thermal properties is quite imperative. This paper deals with the determination of thermal conductivity, thermal diffusivity and volumetric heat capacity of rocks by block method with thermal contact resistance consideration and the validation of the results with that of KD2 device. Thermal properties of granite, limestone and gneiss rocks were determined in the laboratory with the use of thermal interface material (TIM) Arctic Silver to find out the effect of contact resistance. KD2 probe was also used with and without TIM to compare thermal conductivities results. Thermal conductivity of granite, limestone and gneiss increased from 2.96 to 3.96 W/mK, 2.02 to 2.68 W/mK, and 1.64 to 2.20 W/mK respectively while Thermal diffusivity increased from 0.41 x 10-4 to 0.67 × 10-4 m2/s, 1.09 × 10-4 to 7.38 x 10-4 m2/s, and 0.65 x 10-4 to 1.44 x 10-4 m2/s respectively. Thermal conductivities with and without TIM were tested statistically using (FPLSD) and it was found that using TIM to correct contact resistance was significant at (P > 0.05). [ABSTRACT FROM AUTHOR]

Investigation of electrical conductivity of contaminated earth is becoming increasingly relevant in geophysical sciences, where global environmental safety is a key issue. Riverbed sands were collected from the five south-western states of Nigeria, and electrical conductivity determined after samples have been contaminated with varying concentrations of petrol, cow dung, palm oil, manganese (IV) oxide, cement, cassava extract, wood ash, and washing soda. Impact of density was also studied for solid contaminant. Conductivity was largely proportional to contaminant concentration in all the samples in general. However with increase in concentrations of petrol and palm oil, decrease in electrical conductivity of samples was observed while increase in concentrations of other contaminants increased conductivity of samples. Conductivity was also largely influenced by the density of contaminated samples. At higher concentrations of contaminants, conductivity became constant especially when conductivity values of contaminants itself was achieved. [ABSTRACT FROM AUTHOR]