Mineralogical characteristics of harmattan dust in Ilorin, Sub-sahara africa

Abstract

Mineralogical study was carried out on harmattan dust samples collected over Ilorin (8° 32' N, 4° 34' E) sub-Sahara region of West Africa. Minerals such as quartz [SiO₂ ] (76.5%), gibbsite [Al(OH)₃ ] (7.1%), rutile [TiO2 ](5.8%), goethite [Fe₂ O₃.H₂O] (4.6%), halloysite [Al₄ Si₄ O₁₀ (OH)₈ ·8H₂O] (3.9%) and kaolinite [Al₄ Si₄ O₁₀(OH)₈ ](2.1%) were detected. Quartz, halloysite, microcline and mica were similarly identified in harmattan dust sampled at Ile-Ife. However, gibbsite, rutile, goethite which were identified at Ilorin were not detected at Ile-Ife, while microcline and mica detected in Ile-Ife were not observed at Ilorin. The mineralogical composition of the harmattan dust at a locality is most probably determined by the source and the distance from the source of the harmattan dust.

Keywords: Bodele Depression, Harmattan Dust, Mineralogy, Ilorin.