To what extent have laterites contributed to the geochemical, surface reflectance and magnetic properties of adjacent tropical soils? Evidence from Niger and Burkina Faso

摘要: The present study is based on a suite of surface samples from exposures eroded laterite, considered to be Tertiary in age, and nearby soils the Sahelian region SW Niger Burkina Faso. X-Ray Fluorescence (XRF), Diffraction (XRD), Computer Controlled Scanning Electron Microscopy (CCSEM), Energy Dispersive X-ray Spectroscopy (EDS), Diffuse UV/Visual Reflectance (DRS) magnetic measurements have been used shed light origin their possible derivation adjacent, laterite outcrops. On basis wide range data obtained, we conclude that mineralogy properties precludes direct laterites without further weathering modification. Nor does evidence support view evolved entirely independently, uninfluenced by input laterites. only conclusion consistent with all lines erosion provided at least significant part material upon which soil formation took place. This must occurred time early enough permit long period subsequent development during iron oxides, specifically haematite ferrimagnetic minerals, were significantly modified. From this, infer discontinuous has contributed remotely sensed, distinctive reflectance characteristics Sahel surfaces. provide for situ neo-formation fine, secondary, pedogenic magnetite/maghemite grains typical those found many across elsewhere both temperate tropical environments.