The nature and origin of the aeolian mantles of central northern Nigeria

Evidence is presented here to show that the upland soils of central northern Nigeria are formed in aeolian mantles deposited by two aeolian processes: aeolian suspension (or dust) deposition and aeolian saltation (or dune sand) deposition. The soils to the south and west of Kano are largely the product of Harmattan dust deposition, whereas the northern soils appear to originate from dune sand migration from the Quaternary dune fields to the east of the study area. The spatial pattern of particle-size populations (or quanta) and quartz grain roundness characteristics, within the mantles and dune sands, indicates that considerable mixing of dune sands and dust has occurred in the formation of these mantles.