Effect of dry-wet cycles on material composition of badlands

Raghunandan, M.E., and Azam, S. (2012)., Proceedings of 65th Canadian Geotechnical Conference, GeoManitoba 2012, Manitoba, Canada, Paper No. 338, 2012

Geology and climate govern the evolution of badland sediments at Avonlea, Saskatchewan. Given the recent infrastructure development in the area, there is a need to understand the variation in material composition due to alternating dry-wet cycles. The main objective of this paper was to study the effect of drying and wetting on composition of three typical surface sediments: sandstone, mudrock, and pediment. Based on the laboratory testing, results indicate increase in fines from 17% to 34% in sandstone, 4% to 98% in mudrock, and 21% to 42% in pediment. Mineralogical analysis showed dominance of non-clay minerals including quartz (60 to 75%), feldspar (15 to 20%), and calcite (3 to 6%), whereas smectite, illite, kaolinite and chlorite were the clay minerals. Decrease in amount of illite in sandstone and pediment indicate illite being eroded within the layers as result of washing.