Hydrogeological properties of fractured rocks (granites, metasediments and volcanites) under the humid tropical climate of West Africa

  • M. Koïta
  • H. Jourde
Part of the Environmental Earth Sciences book series (EESCI)


This study aims to propose a vertical structuring of water production zones for three types of fractured rocks encountered in Ivory Coast, West Africa. In a first step, the methodology consists of the characterization of the weathering profiles based on: i) bedrocks and weathering layers observations at outcrop; ii) interpretation and synthesis of geophysical data and lithologs from different boreholes. In a second step, the evolution with depth of flow rate (air-lift discharge rates) as well as the frequency and the density of water production zones during drilling are statistically analyzed. Then, the distributions of these various properties versus the depth are fitted to probability laws. For each of the geological formations (granites, metasediments and volcanites) the related weathering profile comprises, from top to bottom, four separate layers: alloterite, isalterite, fissured layer and fractured fresh basement; these weathering profiles are systematically covered by a soil layer. In granites, the maximal values of flow, frequency and density of the water production zones (WPZ) are situated around 40 m depth systematically within the fractured fresh granite layer. In metasediments and volcanites, the maximal values of flow, as well as the maximal frequency and density of WPZ are identified at two distinct depths. The first WPZ, around 40 m depth, is associated to the fissured layer for both profiles; the second WPZ, around 80 m depth is associated to the fractured fresh sandstone layer for the weathering profile in metasediments and to the fractured fresh metabasalt layer, for the weathering profile in volcanites.


Fracture Rock Ivory Coast Hydrogeology Journal Hydrogeological Property Humid Tropical Climate 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.


Unable to display preview. Download preview PDF.

Unable to display preview. Download preview PDF.


  1. Berger J, Camerlo J, Fahy J.C, Haubert M (1980) Etude des ressources en eaux souterraines dans une région de socle cristallin: “la Boucle de cacao” en Côte d’Ivoire. Bull. BRGM. Sér. II. Sect. III. 4, 3350-338Google Scholar
  2. Dewandel B., Lachassagne, P., Wyns R., Maréchal J C., Krishnamurthy NS (2006) A generalized 3-D geological and hydrogeological conceptual model of granites aquifers conrolled by single or multiphase weathering, Journal of Hydrology 330, 260-284CrossRefGoogle Scholar
  3. Finsterle, S., Fabryka-Martin JT., Wang JSY (2002) Migration of a water pulse through fractured porous media. Journal of contaminant Hydrology 54 (2002) 37-57CrossRefGoogle Scholar
  4. Freyssinet P., Farah A S (2000) Geochemical mass balance and weathering rates of ultramafic schists in Amazonia, Chemical Geology 170 (2000), 133-151CrossRefGoogle Scholar
  5. Geirnaert W, Groen M, Van Der Sommen J, Leusink A (1984) Isotope studies as a final stage in groundwater investigations on the African shield, challenges in African Hydrology and water resources (Proceeding of the Harare Symposium, July 1984). IAHS publ. 144, 141-153Google Scholar
  6. Neves M A, Morales N (2007) Well productivity controlling factors in crystalline terrains of southeastern Brazil, Hydrogeology Journal 15, 471-482CrossRefGoogle Scholar
  7. Peltre P (1977) Le «V» baoulé: Héritage géomorphologique et paléoclimatique dans le tracé du contact forêt-savane, Cahier ORSTOM, 190Google Scholar
  8. Taylor R., Howard K (2000) A tectono-geomorphic model of the hydrogeology of deeply weathered crystalline rock: Evidence from Uganda, Hydrogeology Journal, 8:279-294CrossRefGoogle Scholar
  9. Wright E P (1992) The hydrogeology of crystalline basement aquifers in Africa, Geological Society, London, Special Publications, Vol. 66, doi: 10. 1144/GSL.SP.1992.066.01.01, 1-27Google Scholar
  10. Wyns R., Gourry JC., Baltassat JM., Lebert F (1999) Caracterisation multiparametres des horizons de subsurface (0-100 m) en contexte de socle altéré. In: I. BRGM, IRD, UPMC (Eds), 2ème Colloque GEOFCAN, Orléans, France, 105-110Google Scholar
  11. Yao D, Delor C, Gadou G, Kohou P, Okou A, Konaté S, Diaby I (1995) Notice explicative de la carte géologique feuille de Dimbokro, Mémoire SODEMI, Abidjan (Côte d’Ivoire)Google Scholar

Copyright information

© Springer-Verlag Berlin Heidelberg 2011

Authors and Affiliations

  • M. Koïta
    • 1
  • H. Jourde
    • 1
  1. 1.Laboratoire HydroSciences Montpellier UMR 5569Université MontpellierMontpellier Cedex 5France

Personalised recommendations