論文

査読有り
2018年7月1日

Identifying Groundwater Potential in Crystalline Basement Rocks Using Remote Sensing and Electromagnetic Sounding Techniques in Central Western Mozambique

Natural Resources Research
  • Luís André Magaia
  • ,
  • Tada-nori Goto
  • ,
  • Alaa Ahmed Masoud
  • ,
  • Katsuaki Koike

27
3
開始ページ
275
終了ページ
298
記述言語
英語
掲載種別
研究論文(学術雑誌)
DOI
10.1007/s11053-017-9360-5
出版者・発行元
Springer New York LLC

Exploring for groundwater in crystalline rocks in semiarid areas is a challenge because of their complex hydrogeology and low potential yields. An integrated approach was applied in central western Mozambique, in an area covered by Precambrian crystalline basement rocks. The approach combined a digital elevation model (DEM), remote sensing, and a ground-based geophysical survey. The aim was to identify groundwater zones with high potential and to identify geological structures controlling that potential. Lineaments were extracted from the DEM that had been enhanced using an adaptive-tilt, multi-directional, shading technique and a non-filtering technique to characterize the regional fracture system. The shallowness and amount of stored groundwater in the fracture zones was assessed using vegetation indices derived from Landsat 8 OLI images. Then, 14 transient electromagnetic (TEM) survey profiles were taken in different geological settings across continuous lineaments that were considered to be aligned along inferred faults. In the central lineament zones, the TEM soundings gave resistivity values of less than 300 Ωm at a depth of 20–80 m. The values varied with location. Conversely, values greater than 400 Ωm were observed at the sites away from the central zones. This contrast is probably caused by the differences in permeability and degree of weathering along the fractured zones. These differences could be key factors in determining groundwater occurrence. By integrating five water-related factors (lineament density, slope, geology, vegetation index, and proximity to lineaments), high groundwater potential zones were located in the vicinity of the lineaments. In these zones, vegetation remains active regardless of the season.

リンク情報
DOI
https://doi.org/10.1007/s11053-017-9360-5
ID情報
  • DOI : 10.1007/s11053-017-9360-5
  • ISSN : 1573-8981
  • ISSN : 1520-7439
  • SCOPUS ID : 85035098548

エクスポート
BibTeX RIS