الفهرس 
History of falajesOnly 14 pages are availabe for public view
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Abstract
In addition to their importance as a renewable water resource, falajes represent a part of the U. A. E. history. The Falaj is a man-made channel which intercepts ground water at the footslopes of high mountains and brings it to the surface for irrigation purposes. The main objective of this thesis is to study the geological setting and their hydrogeological characters of the A1 Ain falajes. The specific objectives are to: (I) study the climate of A1 Ain area, especially rainfall, (2) investigate the geological setting of Falaj A1 Aini and Falaj A1 Daudi, (3) define the factors affecting discharge and water chemistry of A1 Ain falajes and (4) determine the physical and chemical properties of water in the falajes and evaluate its suitability for different purposes. To achieve these objectives, 73 water samples were collected from the Quaternary aquifer and A1 Ain falajes in May 1995 and March 1996. Water samples were analyzed for major and minor chemical constituents in the Desert and Marine Research Center, U. A. E. University, and A1 Sulaymat Laboratory of the Department of Agriculture, A1 Ain. Results indicate that the A1 Ain falajes obtain their water mainly from the Quaternary alluvial aquifer. The sediments penetrated by the shafts of Falaj A1 Aini and Falaj A1 Daudi consists of, from base to top: crystalline limestone, calcareous mudstone, packstone, grainstone and ophiolitic conglomerate. The major rock-forming minerals identified by X-ray diffraction are calcite and dolomite. The minor minerals are lizardite, quartz, iron oxides and clay minerals. During the 1978- 1995 period, the total falaj discharge in the U. A. E. varied between 9.0 x lo6 m31yr in 1994 and 3 1.2 x 1 o6 m31yr in 1982, which represented 2.8 to 9.7%, respectively, of the total water use in the country. The salinity and concentrations of Fe, Mn, Cu, Co, Ni, Zn, Pb and Cd in water ofthe A1 Ain falajes are low and below the limits recommended by the World Health Organization (WHO) for drinking water. The dissolved salts in water of the falajes are Mg(HCO,), and Ca(HCO,), in the eastern part of the study area, and MgSO, and CaSO, in the west. The measured the electrical conductance (EC) and calculated sodium adsorption ratio (SAR) indicate that, except for the parts around and west of Jabal Hafit, the water of the A1 Ain falajes are excellent for irrigation purposes.