Geotechnical analysis of two Nigerian soils for use as clay liners

The cretaceous Auchi shale and the Tertiary Imo shale in SW Nigeria were investigated for their suit- ability for use as a clay seal in waste disposal landfills. Geotechnical analyses indicated they are highly plastic inorganic clays. Although their geotechnical and chemical properties were within the range suggested by various authors for use as mineral seals, care would need to be taken with the Okada shales as they contain smectite and would be difficult to work and liable to cracking.