Environmental Hydrochemistry and Seasonal Variations in Radon Concentration in Geno Hot Spring, North of Hormozgan, Iran

Article history: Geno hot spring is one of the famous hot springs and hydrotherapy centers in Iran which has been used since ancient times. The spring is located on the eastern edge of anticline of double plunges of Geno from the series of Zagros folded corrosion. The average water temperature in Geno hot spring is 41/22 ° C and releases a strong odor of hydrogen sulfide due to sulfate rduction. The water type is sodium chloride (Na-Cl) due to the outcrop of salt domes of Hormuz Series, possible flow of water at great depth and flows back to the surface. The water is in a relative maturity and has reached a rather equilibrium with its rock repository. Weak correlation between magnesium and chloride ions in the samples of Geno hot spring can be the result of mixing of surface waters with deep brine. The water is saturated toward aragonite, calcite and dolomite and is under saturated toward phases such as gypsum, halite and anhydrite. Water temperature in the reservoir of Geno hot spring is estimated to be 55 to 154 0 C based on