Gana’da bazı topluluklarında elektromanyetik ve elektrik rezistivite yöntemlerle kullunılarak yeraltı su kaynakları araştırması
Yıl 2016,
, 133 - 139, 01.08.2016
Hafiz Mohammed Nazifi
,
Levent Gülen
,
Can Karavul
Öz
Gana’ nın merkez bölgesinde bulunan Twifo – Hemang Lower Denkyira ilçesindeki bazı topluluklardan yüksek yeraltı su potansiyeline sahip bölgeleri belirlemek ve belirlenen bu yerler doğrultusunda toplulukların su ihtiyacını karşılayabilecek uygun sondaj yerleri önermek için Elektromanyetik (EM) Profili ve Düşey Elektrik Sondajı (DES) verileri alınmıştır. Bu çalışmada, sırasıyla Esukese Ekyire, Kwanyarko ve Nyameyeadom kasabalarına ait etüd sonuçları tartışılacaktır. İlk olarak, EM ölçülerin alımı gerçekleştirilmiştir. Daha sonra EM verileri nitelik olarak yorumlanmış ve bunun sonucunda çatlak ve/veya kırık zonları tespit edilmiştir. Schlumberger elektrot dizilimi kullanılarak DES ölçümleri kayaç bozunması gözlenen noktalarda elektromanyetik ölçüm alınan yerlerde yapılmıştır. ZONDIP1D yazılımı, sondaj noktaları altındaki jeolojik yeraltı yapılarının 1D sondaj eğri modellerinin üretilmesinde kullanılmıştır. Modellemenin sonuçları bölgede üç veya dört jeolojik zon bulunduğunu göstermiştir. DES verilerinin 1D ters çözümü yorumlamaları katmanlarının özdirenç ve kalınlık değerlerini vermektedir. Su temini için gerekli olan sondaj kuyu yerleri 1D sondaj eğrisi modeli ve yeraltı katmanlarının kalınlıklarına göre önerilmiştir.
Kaynakça
- D. V Fitterman and M. T. Stewartj, “Transient electromagnetic sounding for groundwater,” Geophysics, vol. 51, no. 4, pp. 995–1005, 1986.
- E. Obuobie and B. Barry, “Groundwater in sub-Saharan Africa : Implications for food security and livelihoods.,” Accra, Ghana, 2010.
- P. Gyau-Boakye and S. Dapaah-Siakwan, “Groundwater as source of Rural Water supply in Ghana,” Jounal Appl. Sci. anf Technol., vol. 5, no. 1 & 2, pp. 77–86, 2000.
- W. M. Telford, L. P. Geldart, and R. E. Sheriff, Telford - Applied Geophysics. 1990.
- P. Kearey, M. Brooks, and I. Hill, An Introduction to Geophysical Exploration, 3rd ed. Iowa: Blackwell Science Ltd, 2002.
- J. M. Reynolds, An Introduction to Applied and Environmental Geophysics, First. West Sussex, England: John Wiley & Sons Ltd., 1997.
- P. V. Sharma, Environmental and Engineering Geophysics, vol. 20. Cambridge University Press, 1997.
- E. Robinson S. and C. Çoruh, Basic Exploration Geophysics. Singapore: John Wiley & Sons Ltd., 1988.
- K. Reinhard, Ed., Groundwater Geophysics: A TOOL FOR HYDROGEOLOGY. Heidelberg, Germany: Springer, 2006.
- G. O. Kesse, The mineral and rock resources of Ghana. Rotterdam, Netherlands: A. A. Balkema, 1985.
- E. A. Gyamera and J. S. Kuma, “Hydrogeological studies on soils developed over granitic deposits,” vol. 2, pp. 29–40, 2014.
- B. K. Beeson and C. R. C. Jones, “The Combined EMT/VES Geophysical Method of Siting Boreholes,” Groundwater, vol. 26, no. No.1, p. pp 54–63., 1988.
- A. Roy and A. Apparao, “Depth of Investigation in Direct Current Methods,” Geophysics, vol. 36, no. 5, pp. 943–959, 1971.
- P. Okafor and L. Mamah, “Integration of Geophysical Techniques for Groundwater Potential Investigation in Katsina - Ala, Benue State, Nigeria,” Pract. J. Sci. Technol., vol. 13, no. 2, pp. 463–474, 2012.
- G. O. Omosuyi, “Geoelectric Assessment of Groundwater Prospect and Vulnerability of Overburden Aquifers at Idanre, Southwestern Nigeria,” Ozean J. Appl. Sci., vol. 3, no. 1, pp. 19 – 28, 2010.
- P. R. Worthington, “Geophysical Investigations of Groundwater Resources in the Kalahari Basin,” Geophysics, vol. 42, no. 4, pp. 838 – 849, 1977.
Groundwater investigations in Ghana using electromagnetic and electrical resistivity methods
Yıl 2016,
, 133 - 139, 01.08.2016
Hafiz Mohammed Nazifi
,
Levent Gülen
,
Can Karavul
Öz
The electromagnetic profiling and Vertical Electrical Sounding (VES) data were acquired from some communities in the Twifo – Hemang Lower Denkyira District of the Central region of Ghana, in order to determine zones of high groundwater potentials and to recommend suitable sites to drill boreholes for community water supply. The research reported here covered three communities namely; Esukese Ekyire, Kwanyarko. First the electromagnetic measurements were carried out, qualitative interpretations of the data were carried out and weathered rock zones were identified. Then the VES measurements using Schlumberger array were conducted at points on the electromagnetic traverse that displayed weathered zones. ZONDIP1D software was used in creating 1D sounding curve models of geological subsurface structures beneath the sounding points. Results of the modelling suggest that the communities are underlain by three to four geological layers. Interpretations of the 1D inversion of the VES data provide the resistivities and thicknesses of subsurface layers. On the basis of resistivity values and thicknesses of the layers in the 1D models, sites were recommended to drill boreholes for community water supply.
Kaynakça
- D. V Fitterman and M. T. Stewartj, “Transient electromagnetic sounding for groundwater,” Geophysics, vol. 51, no. 4, pp. 995–1005, 1986.
- E. Obuobie and B. Barry, “Groundwater in sub-Saharan Africa : Implications for food security and livelihoods.,” Accra, Ghana, 2010.
- P. Gyau-Boakye and S. Dapaah-Siakwan, “Groundwater as source of Rural Water supply in Ghana,” Jounal Appl. Sci. anf Technol., vol. 5, no. 1 & 2, pp. 77–86, 2000.
- W. M. Telford, L. P. Geldart, and R. E. Sheriff, Telford - Applied Geophysics. 1990.
- P. Kearey, M. Brooks, and I. Hill, An Introduction to Geophysical Exploration, 3rd ed. Iowa: Blackwell Science Ltd, 2002.
- J. M. Reynolds, An Introduction to Applied and Environmental Geophysics, First. West Sussex, England: John Wiley & Sons Ltd., 1997.
- P. V. Sharma, Environmental and Engineering Geophysics, vol. 20. Cambridge University Press, 1997.
- E. Robinson S. and C. Çoruh, Basic Exploration Geophysics. Singapore: John Wiley & Sons Ltd., 1988.
- K. Reinhard, Ed., Groundwater Geophysics: A TOOL FOR HYDROGEOLOGY. Heidelberg, Germany: Springer, 2006.
- G. O. Kesse, The mineral and rock resources of Ghana. Rotterdam, Netherlands: A. A. Balkema, 1985.
- E. A. Gyamera and J. S. Kuma, “Hydrogeological studies on soils developed over granitic deposits,” vol. 2, pp. 29–40, 2014.
- B. K. Beeson and C. R. C. Jones, “The Combined EMT/VES Geophysical Method of Siting Boreholes,” Groundwater, vol. 26, no. No.1, p. pp 54–63., 1988.
- A. Roy and A. Apparao, “Depth of Investigation in Direct Current Methods,” Geophysics, vol. 36, no. 5, pp. 943–959, 1971.
- P. Okafor and L. Mamah, “Integration of Geophysical Techniques for Groundwater Potential Investigation in Katsina - Ala, Benue State, Nigeria,” Pract. J. Sci. Technol., vol. 13, no. 2, pp. 463–474, 2012.
- G. O. Omosuyi, “Geoelectric Assessment of Groundwater Prospect and Vulnerability of Overburden Aquifers at Idanre, Southwestern Nigeria,” Ozean J. Appl. Sci., vol. 3, no. 1, pp. 19 – 28, 2010.
- P. R. Worthington, “Geophysical Investigations of Groundwater Resources in the Kalahari Basin,” Geophysics, vol. 42, no. 4, pp. 838 – 849, 1977.