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Volume 36 Number 10
  • ISSN: 0263-5046
  • E-ISSN: 1365-2397

Abstract

Abstract

Freshwater availability is a growing problem all over the world. This is especially true in drier regions with marked population growth. That is the case at the Cape Verde archipelago off the coast of West Africa. The problem of water availability has been part of the archipelago’s history since the 15th century, when these uninhabited islands were discovered by Portuguese navigators. The inconstancy and shortage of drinking water has always been related to low rainfall and prolonged drought. Most of the islands do not have high elevations, which does not favour orographic precipitation. Population and agricultural activity have always been limited by the use of existing water; either stored from the rainy season or from wells excavated in the valley’s riverbanks. To overcame this condition many boreholes have been drilled since the 1950s and 1960s at the known aquifiers. This was done under the scope of geologic and hydrogeological data and methods. The present study is an electromagnetic geophysical survey at Santiago Island, the biggest and most populated of the archipelago. Beginning in 2005, there was at least one campaign a year until 2009. The surveyed regions are the most important valleys and agricultural areas, where the water needs are bigger. The problem of groundwater is not just its amount and availability but also its quality. The problem of sea or salty water intrusion into the near sea groundwater aquifers was detected at many boreholes and by the wells’ hydrochemistry data. The aim of this EM survey was to image the groundwater condition; location and quality throughout the studied areas. To fulfill this, transient electroMagnetic (TEM) soundings have been done. In addition some very low frequency (VLF) profiles and magnetoteluric (MT) soundings have been carried on to confirm and cross-check TEM data.

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2018-10-01
2024-04-19

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References

  1. Bear, J., Cheng, A. H-D., Sorek, S., Ouazar, D. and Herrera, I.
    [1999]. Seawater intrusion in coastal aquifers – concepts, methods and practices.Kluwer Academic Publishers, Dordrecht.
     [Google Scholar]
  2. Carreira, P. M., Marques, J. M., Pina, A.
    , et al. [2010]. Groundwater assessment at Santiago Island (Cabo Verde): a multidisciplinary approach to a recurring source of water supply.Water Resources Management, 24, 1139–1159.
     [Google Scholar]
  3. Egbert, G.D., Booker, J.R.
    , [1986]. Robust estimation of geomagnetic transfer functions.Geophysical Journal of the Royal Astronomical Society, 87, 173–194.
     [Google Scholar]
  4. Gonçalves, R.
    [2012]. Hydrochemical water prediction (water quality) with transient electromagnetic soundings (TEM). PhD thesis, University of Lisbon, Portugal, 314.
     [Google Scholar]
  5. Gonçalves, R., MohammadF., Monteiro Santos, F., Represas, P., Gomes, M., Pina, A. F., Almeida, E.
    , [2017]. Application of Time-Domain Electromagnetic Method in Investigating Saltwater Intrusion of Santiago Island (Cape Verde), Pure and Applied Geophysics, Springer International Publishing AG. DOI 10.1007/s00024‑017‑1642‑7.
     https://doi.org/10.1007/s00024-017-1642-7 [Google Scholar]
  6. Kaufman, A.A. and Keller, G.V.
    [1983]. Frequency and transient soundings.Amsterdam, Elsevier.
     [Google Scholar]
  7. Matos Alves, C.A., Macedo, J.R., Celestino Silva, L., Serralheiro, A., Peixoto Faria, A.F.
    , [1979]. Geologic, petrological and vulcanological study of Santiago Island (Cape Verde). Revista Garcia de Orta, Série de Geologia, 3 (1–2), 70–81.
     [Google Scholar]
  8. Mota Gomes, A.
    , [2007]. Hidrogeologia e recursos hídricos da ilha de Santiago (Cabo Verde). PhD thesis, University of Aveiro, 296, (in Portuguese).
     [Google Scholar]
  9. Monteiro Santos, F.A., Almeida, E.P., Gomes, A.M. and Pina, A.F.L.
    [2006]. Hydrogeological investigation in Santiago Island (Cabo Verde) using magnetotellurics and VLF methods.Journal of African Earth Sciences, 45, 421–430.
     [Google Scholar]
  10. Nabighian, M. and MacnaeJ.
    [1991]. The magnetotelluric method. In: M.N.Nabighian (Ed.), Electromagnetic methods in applied geophysics, Vol. 2, Society of Exploration Geophysicists.
     [Google Scholar]
  11. Pina, A.F.
    [2009]. Hydrochemistry and quality in the groundwater of Santiago Island– Cabo Verde. PhD thesis, University of Aveiro, 208 (in Portuguese).
     [Google Scholar]
  12. Ramalho, R., Helffrich, G., Cosca, M., Vance, D., Hoffmann, D. and Schmidt, D. N.
    [2010a]. Episodic swell growth inferred from variable uplift of the Cape Verde hotspot islands.Nature Geoscience, 3, 774–777.
     [Google Scholar]
  13. [2010b]. Vertical movements of ocean island volcanoes: insights from a stationary plate environment.Marine Geology, 275, 84–95.
     [Google Scholar]
  14. Ramalho, R., Helffrich, G., Schmidt, D. N. and Vance, D.
    [2010c]. Tracers of uplift and subsidence in the Cape Verde archipelago.Journal of the Geological Society, 167, 1–19.
     [Google Scholar]
  15. Serralheiro, A.
    , [1974]. A Geologia da Ilha de Santiago (Cabo Verde). PhD thesis, University of Lisbon, 218, (in Portuguese).
     [Google Scholar]
  16. Schön, J. H.
    [1998]. Physical properties of rocks. Fundamentals and Principles of Petrophysics.Handbook of geophysical exploration seismic exploration, 18. Elsevier, Oxford, 583.
     [Google Scholar]
  17. Vozoff, K.
    [1991]. The magnetotelluric method. In: Nabighian, M.N. (Ed.), Electromagnetic Methods in Applied Geophysics II. Soc. Exp. Geophys, 641–711.
     [Google Scholar]
  18. TEM-RESearcher manual.
    TEM-RESearcher manual. [2007]. Version 7, Applied electromagnetic research (AEMR), the Netherlands.
     [Google Scholar]
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Water resources detection at Santiago Island, Cape Verde using electromagnetic methods
First Break 36, 53 (2018); https://doi.org/10.3997/1365-2397.n0126
/content/journals/10.3997/1365-2397.n0126
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  • Article Type: Research Article

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