| Badlands are characterized by rills, gullies and steep cemented sandstone slopes rising above pedimented materials with intervening mudrock slopes. These distinct features closely reflect lithologic variations and different erosion resistance of the various materials. Badlands engineering behaviour is governed by materials composition, climatic and environmental factors. Based on field observations and laboratory investigations, this research characterized badland sediments from Avonlea, located (latitude 50 01° N, longitude 104 59° W) at a distance of about 60 km SSW of Regina, Saskatchewan.;Sample mineralogical compositions were determined to be; 15% clay, 85% non clay and 52% calcite for the cemented sandstone, 79% clay, 21% non clay and 19% smectite for the weathered mudrock and 9% clay, 91 non clay and 17% calcite for the basal pediment. Swelling potential for the samples were calculated to be; (SP = 9%) for the cemented sandstone, (SP = 13%) for the weathered mudrock and (SP = 0.3%) for the basal pediment, respectively.;The hydraulic conductivity---void ratio relationships was found to obey the power law function and the trends for cemented sandstone and basal pediment were similar and steep. In contrast, the hydraulic conductivity trend was flatter for the weathered mudrock and spanned over a wider void ratio range. Mineralogical composition correlated well with the geology of the area, volume change and geotechnical index properties of samples.;Field investigation revealed the presence of rills, gullies and steep sided slopes in the cemented sandstone, desiccation cracks in the weathered mudrock and flat alluvial deposition in the basal pediments. Laboratory investigations conducted on surface samples retrieved from three distinct slope surfaces, namely; cemented sandstone, a mid-slope formed in bentonitic weathered mudrock, and a relatively flat basal pediment surface, revealed that Avonlea badlands exhibit extensive variability in the engineering properties during seasonal climate variations causing alternative cycles of saturation and desiccation. Consistency limits indicated high water adsorption capabilities in the weathered mudrock (WL = 67.6%, Wp = 45.9%), followed by the cemented sandstone (WL = 39.9%, Wp = 31.2%) and then basal pediment (WL = 24.5%, Wp = 21.9%). Grain size distribution analysis signified the phenomenon of grain size thinning in which the fine size contents (materials finer than 0.075mm) increased by 17%, 78%, and 35% in the cemented sandstone, weathered mudrock and basal pediment, respectively, due to saturation. |
