Metelka V., Baratoux Lenka, Jessell Mark, Naba S. (2015). Visible and infrared properties of unaltered to weathered rocks from Precambrian granite-greenstone terrains of the West African Craton. In :
Jessell Mark (ed.), Liégeois J.P. (ed.). Tectonics, mineralisation and regolith evolution of the West African Craton. Journal of African Earth Sciences, 112, part B (No spécial), p. 570-585. ISSN 1464-343X.
Titre du document
Visible and infrared properties of unaltered to weathered rocks from Precambrian granite-greenstone terrains of the West African Craton
Année de publication
2015
Auteurs
Metelka V., Baratoux Lenka, Jessell Mark, Naba S.
In
Jessell Mark (ed.), Liégeois J.P. (ed.), Tectonics, mineralisation and regolith evolution of the West African Craton
Source
Journal of African Earth Sciences, 2015,
112, part B (No spécial), p. 570-585 ISSN 1464-343X
In situ and laboratory 0.35 mu m-2.5 mu m spectra of rocks from a Paleoproterozoic granite-greenstone terrain along with its Neoproterozoic sedimentary cover and derived regolith materials were examined in western Burkina Faso. The reflectance spectra show the influence of typical arid to semi-arid weathering with the formation of desert varnish, iron films, and dust coatings. Fe and Mg-OH absorption features related to chlorite, amphibole, pyroxene, epidote, and biotite are observable in the mafic and intermediate meta-volcanic rocks as well as in the granodiorites and tonalites. Al-OH absorption caused by kaolinite, smectite, illite/muscovite are typical for meta-volcano-sedimentary schists, Tarlcwaian-type detrital meta-sediments, sandstones of the Taoudeni basin, all of the weathered surfaces and regolith materials. Ferric and ferrous iron absorptions related to both primary rock-forming minerals and secondary weathering minerals (goethite, hematite) were observed in most of the sampled materials. The results show that although weathering alters the spectral signature of the fresh rock, indicative absorption features located in the short wave infrared region remain detectable. In addition, spectra of soils partially reflect the mineral composition of the weathered rock surfaces. The analysis of the hyperspectral data shows the potential of differentiating between the sampled surfaces. The library presents a primary database for the geological and regolith analysis of remote sensing data in West Africa.
Plan de classement
Géologie et formations superficielles [064]
;
Pédologie [068]
;
Etudes, transformation, conservation du milieu naturel [082]
Description Géographique
AFRIQUE DE L'OUEST ; BURKINA FASO ; ZONE ARIDE
Localisation
Fonds IRD [F B010066073]
Identifiant IRD
fdi:010066073
