GEOSCAN, résultats de la recherche


TitreAirborne electromagnetic surveys over concealed glacial aquifers, United States and Canada
AuteurSmith, B D; Abraham, J A; Lundstrom, S C; Oldenborger, G
SourceProceedings of Near Surface 2010 - 16th European Meeting of Environmental and Engineering Geophysics; 2010, 4 pages
Séries alt.Secteur des sciences de la Terre, Contribution externe 20100216
RéunionNear Surface 2010, 16th European Meeting of Environmental and Engineering Geophysics; Zurich; CH; Septembre 6-8, 2010
Sujetslevés géophysiques; levés magnétiques; levés électromagnétiques; levés aéroélectromagnétiques; aquifères; eau souterraine; ressources en eau souterraine; dépôts glaciaires; elements glaciaires; géophysique; hydrogéologie; géologie des dépôts meubles/géomorphologie
Illustrationslocation maps
ProgrammeAquifer Assessment & support to mapping, Géoscience des eaux souterraines
Résumé(disponible en anglais seulement)
Over the last decade, helicopter electromagnetic (HEM) frequency and time domain (HFEM and HTEM) electrical resistivity surveys have been performed over buried glacial features that constitute major aquifers in different regions of central North America. These surveys have been conducted to map geology, contaminants, and hydrogeology for groundwater studies. This paper summarizes the applications in four different glacial terrains. The HFEM systems applied in the surveys described here used frequencies from 400 to 140,000 Hz that, in electrically conductive areas may be limited to mapping depths less than 60 m. The HTEM survey described here used gate times from 50 microseconds to 5.4 milliseconds and can map to depths of more than 100 m. The HEM surveys provide an insight into subsurface mapping capabilities and into the hydrogeologic framework of buried glacial valleys that host important local and regional aquifers.