The origin of Garow saline water springs, are located 50 km South of Mashhad city-Iran, and the groundwater quality in these springs are investigated using geochemistry and stable isotopes. Garow springs is surrounded by red sediments of Neogene formation and precipitated travertan. Field observation indicated that these spring are faulty conducted. However, the high electrical conductivity (11000 μmohs/cm), high concentration of Na, Cl, and SO4 (3150, 2870, 1375 mg/l, respectively) and scaping gass bobles from these springs is attributed to the long residence time of water and firly deep origination of water. The 18O and 2H isotopes and the carbon isotope mass balance between three water, solid and gass phases indicates strong rock/water intractions. In general, the fairly enriched 13C value of dissolved inorganic carbon in springs water (average of 5.8 permill) confirms the contribution of calcite dissolution from geological formations and CO2 releasing at lower depth due to precipitation of travertan (with average of 11 permill).

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