An Integrated Approach for Assessment of Groundwater Potentialities Arid Areas
Abstract
We applied an integrated approach to assess the ground water potentiality in the Eastern Desert (ED) of Egypt. Inferences from a wide range of data sets (Remote sensing: [Landsat TM, SIR-C, SRTM, TRMM]; geochemical [O, H stable isotope composition, solute chemistry], geological [structures, lithology], hydrological [lithology, water table, etc.,] were used to address the nature and sources of groundwater in the Eastern Desert (ED) and to determine the groundwater potentialities across area. Data integration, analysis, and visualization was conducted in a GIS environment. Three potential ground water sources were identified. The first is the shallow alluvial aquifers that fossil water of the Nubian Aquifer. The Nubian Aquifer deep water access the deep and sub-vertical fault systems defining the River Nile graben, and the Gulf of Suez graben. Criteria used in the definition of these reservoirs are: (a) isotopic compositions similar to those of paleo-water in the Eastern Desert, (b) NW-trending fault systems intersecting or bounding the alluvial sediments in question, and (c) presence of thick alluvial deposits proximal to the deep seated faults. The second is meteoric precipitation over the Red Sea hills that are channeled as surface runoff in the valleys and as subsurface groundwater flow in the underlying alluvial aquifers; a portion of this water gets trapped within underlying highly fractured basement reservoirs. Criteria used in the definition of these reservoirs are: (a) well-developed drainage network across a large area within the crystalline basement (~300 km2) (b) within the targeted watersheds, valleys are narrow and are floored by minimal alluvial deposits to minimize losses within the valley network to evaporation, (c) intersecting fracture patterns and/or shear zones that promote porosity, (d) presence of rock types that readily dissolve (e.g., carbonates) within the fractured system. The third is sporadic precipitation over extensive networks encompassing the crystalline basement and adjacent sedimentary that ultimately recharge the alluvial aquifers draining the main valleys within the network. Criteria used in the definition of these reservoirs are: (a) presence of extensive drainage network across the Eastern Desert, (b) isotopic compositions similar to those of present meteoric precipitation, and (c) thick alluvial deposits (e.g., proximity of River Nile Graben).
- Publication:
-
AGU Spring Meeting Abstracts
- Pub Date:
- May 2005
- Bibcode:
- 2005AGUSM.H21C..05M
- Keywords:
-
- 1640 Remote sensing;
- 1800 HYDROLOGY;
- 1829 Groundwater hydrology;
- 9305 Africa