الفهرس 
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Abstract
The study area is located between Belbies and the north Tenth of Ramadan cities, southeast of the Nile Delta, Egypt. The present work aimed to delineate the shallow Quaternary and deep Miocene groundwater aquifers in this area to search for additional water resources for suitable developments using hydrogeological and geophysical investigations. The DC resistivity, time-domain electro-magnetic (TDEM) and magneto-telluric (MT) geophysical techniques are applied for this purpose. The quantitative interpretation of the above data was carried out at thirty-two sites along with the main four profiles in the study area to obtain the true resistivity and thicknesses of subsurface layers by using many inversion algorithms. from the 1D lateral constrained (1D-LCI) inversion results of DC resistivity data, 1D inversion results of time-domain electro-magnetic data, and the DC-TDEM joint inversions results, five geo-electrical layers are identified and they are interpreted into four geological layers along with the main profiles. The last layer shows a low resistivity value (10.7 to 110 Ω.m) and recorded depth ranging between 34.5 m and 138.8 m. It consists probably of saturated sand that may represent the water-bearing formations of the shallow Quaternary aquifer. These results agree with the geological information from the nearest water wells where the top depth of the shallow Quaternary aquifer begin at 80 m. from the 1D inversion of MT data and DC-MT joint inversion results, seven geo-electrical layers were estimated along with the all profiles. Only eight and nine geo-electrical layers were estimated only at some sites. These geo-electric layers can be interpreted with five geological layers. The resistivity value of the deep Miocene aquifer zone ranges between 0.9 Ω.m and 57.8 Ω.m, which are found at depths from 158 m to 268 m. Finally, the above results agree with the previous studies which applied on the Tenth of Ramadan City and its surroundings where the water depth of this aquifer varies from 160 m to 240 m. Also, these results agree with the information from nearest water wells where the top depth of the Miocene sediments including the deep Miocene aquifer begins at depth of 180 m. from true resistivity maps of the deep Miocene aquifer in the study area, the top depth for this aquifer decreases toward the south and south-eastern part where both of the shallow Quaternary and deep Miocene aquifers may be interconnected in the southern part of the study area and the groundwater aquifers are mixed. This agrees with the previous hydrogeological sections’ studies in the study area where the both aquifers are interconnected directly south of the Tenth of Ramadan City. The 2D-DC inversion results reflect three mains, where the last conductive layer (5 Ω.m) reflects the saturated zone of the groundwater aquifer where its depth around 100 m. The 2D-MT inversion results show two low resistivity zones; the first zone (10 to 30 Ω.m) presents at shallow depth between 80 m and 100 m which may indicate the shallow Quaternary aquifer, and the other zone (1 to 3 Ω.m) at deeper depth of about 200 m which may indicate the deep Miocene aquifer. The study area seems to be affected by some normal faults which take a direction perpendicular to the main profiles (N-S) at the southern part near from the Tenth of Ramadan City that agree with the previous known geology. These faults form horst structures that control upward water leakage and interconnection between the shallow Quaternary and deep Miocene aquifers. They may act as a barrier and prevent the lateral movement of groundwater inside these aquifers. Finally, it is recommended to add new water wells in the newly reclaimed arid area, and to apply the 1D-LCI inversion technique, and 1D and 2D joint inversion techniques on all data sets in case of studying the areas with few wells and the geological information.