Scientific publications
Ondoua Oyono Joseph Sadrac
Ipan Antoinette Solange
Edima Yana Roland William
Bidjo Emvoutou Géry Christian
Bitom Dieudonné
Journal of Geosciences and Geomatics
The aim of the present study is to characterize a weathering mantle developed on pelitic rock in the tropical forest region precisely in Mintom (South East Cameroun). This characterization include morphology, physico-chemical and mineralogic analyses. The region is characterize by a hot and wet climate consisting of four seasons of inequal length and intensity. The average temperature is about 24°C and the mean rainfall is about 1633mm/years. The rocks in the area consist of limestone, dolomites and pelites. Fieldwork consist of landscape analysis, geologic prospection and soil profile description. Mineralogical and physico-chemical was carried out on various samples in the laboratory. Morphological results show that the studied profile has a general brownish yellow aspect, with a thickness of about 6m and a silty-clayey texture. Five horizons can be distinguished from top to bottom: a humiferous horizon, a loose yellow set, a yellow horizon bearing quartz fragments and large indurated blocks, a saprolite consisting of a fine and coarse saprolite possessing some pelite relics of variable sizes and a deep red colour just like that of the parent rock. The parent rock is a massive pelite with a reddish colour when wet and a violet colour when dry. It has a powdery feel. Analytically, the soils have an acidic pH (4,0 to 4,2), a high organic matter content (4,8%), a C/N ratio of about 6,76, a cationic exchange capacity of 7,64meq/100g with a saturation rate S/T of about 7. Particle size distribution shows that the silty fraction is dominant (59%), followed by the clayey fraction (30%). The main minerals are kaolinite, quartz, smectites, calcites, dolomites, goethite and hematite.
