Asian Journal of Earth Sciences1819-18862152-3509Science International10.3923/ajes.2008.16.30Al-HarbiOmar HussainG. KhanM.M. 1200811Al-Awshaziyah inland sabkha is an elongated north-south depression, almost flat, enclosed by Khuff Formation (Permian-Triassic) in Al-Qaseem region, Saudi Arabia. It is situated between latitude 26° N and longitude 44° E. and covers more than 18 km2. The area is an important agricultural region in Saudi Arabia due to its huge groundwater reserves. A field study was carried out to determine the hydrogeochemical processes and the isotopic characteristics of the Sabkha for its management and rehabilitation. Sabkha water is highly saline, where the dominant cations concentration order is Na+ >Mg++ >K+ >Ca++ and that of anions is Cl– >SO4–G>NO3– >HCO3–. The total dissolved solids (TDS) of the Sabkha water ranged from 124860-464750 mg L–1 with an average value of 351670 mg L–1. Sabkha water is dominant by sodium-magnesium chloride, magnesium-sodium-chloride and sodium-chloride water types. Halite is the most abundant evaporate mineral which is an economic source of NaCl salt in the region. The dominant cations and anions concentration order of shallow wells is Na+ >Ca++ >Mg++ >K+ and Cl– >SO4–G->NO3– >HCO3 –, respectively. Whereas the dominant cations and anions concentration order of deep wells is Na+ >Ca++ >Mg++ >K+ and SO4–->Cl– >NO3–>HCO3–, respectively. The total dissolved solids (TDS) ranged from 7184-9952 mg L–1 with an average value of 8982 mg L–1 for the shallow wells and from 4340-8580 mg L–1 with an average value of 6265 mg L–1 for the deep wells. The hydro-geochemical processes and the isotopic composition (δ18O and δ2H) indicated that the source of Sabkha water, shallow wells and deep well water is of meteoric origin. It also showed some mixing and ion-exchange phenomenon between Sabkha water, shallow and deep well waters. Further investigations are needed to explore more about the occurrence of these inland Sabkhas and their environmental impact in the area.]]>Al-Alawi, J. and M. Abdul Razzak,19941994Al-Harbi, O.A., G. Hussain and M.M. Khan,200620117132Ali, K.M. and D. Hossain,198871723Andreo, Y.D.,20042004Aqrawi, M.,1995152259268Bayumi, T.H., M.S. Alyamani, M.S. Subyani and M.E. Al-Ahmadi,20042004Bhatt, K.B. and S. Saklani,199648171182BRGM.,19841st Edn.,Delfour, J., R. Dhellemmes, P. Elsaaa, D. Vaslet, J. Brosse, Y. M. Le Nindre and O. Dottin,19821982Duffy, C.J. and S. Al-Hasan,19882416751688Hamdi-Aissa, B., V. Valles, A. Aventurier and O. Ribozi,200418103106Hem, J.D.,19921992Hossain, D. and K.M. Ali,198821347359Hsu, K.J.,19631288310Hsu, K.J. and C. Siegenthaler,1969121126James, A.N. and A.L. Little,198619209214Lloyd, J.W. and J.A. Heathcote,19851st Edn.,pp: 296-296pp: 296-296Manivit, J., D. Vaslet, A. Berthianx, P. Snet and J. Fourniguet,19861986Oweis, I. and J. Bowman,1981107319338Parkhurst, D.L.,19951995Portugal, E.A. and B.I. Romero,200688139143Rodriguez-Rodriguez, M.,20022002Rodriguez-Rodriguez, M., J. Benavente, J.J.J. Cruz-San and F. Moral Martos,200666272289Sabtan, A.A. and W.M. Shehata,200321423429MAW,19851st Edn.,White, D.E., J.D. Hem, G.A. Waring,19631963