TITLE:
Relevance of AEM and TEM to Detect the Groundwater Aquifer at Faiyum Oasis Area, Faiyum, Egypt
AUTHORS:
A. A. Basheer, A. I. Taha, A. El-Kotb, F. A. Abdalla, S. O. Elkhateeb
KEYWORDS:
Airborne Electromagnetic [Frequency-Domain], Ground Electromagnetic [Time-Domain] AEM, TEM, Hydrogeophysics, Al Faiyum Oasis/Lake, Egypt
JOURNAL NAME:
International Journal of Geosciences,
Vol.5 No.6,
May
16,
2014
ABSTRACT:
This study
investigates the groundwater aquifer located in Fayuim oasis. In this study, two
of the electromagnetic measurement methods have been used in determining the hydrological
situation in the Fayoum oasis. The first is airborne electromagnetic (AEM) which,
sometimes is referred to as Helicopter electromagnetic (HEM) and the second is ground
Time-domain Electromagnetic method (TEM). The subsurface consists of four geoelectrical
layers with a rough slope towards the center. The third and the fourth layers in
the succession are suggested to be the two-groundwater aquifers. The third layer
saturates with fresh water overlying saline water which exists in the bottom of
the second one. It is worth mentioning that the depth of the fresh water surface
undulates between the surface level in two lakes in the study area and 57 meters
below the ground, whereas the thickness of the fresh water aquifer varies from 13
to 36 meters. The depth of the saline water surface undulates between 59 and 81
meters below the ground. In general, airborne electromagnetic surveying has the
advantage of fast resistivity mapping with high lateral resolution. Groundbased
geophysical surveys are often more accurate, but they are definitely slower than
airborne surveys. It depends on targets of interest, time, budget, and manpower
available by the method or the combination of methods that will be chosen. A combination
of different methods is useful to obtain a detailed understanding of the subsurface
resistivity distribution.