Chemical Survey and Reservoir Temperature Estimations of Tbilisi Geothermal Deposit by Application of Silica-Enthalpy Mixing Method

Nino A. Kapanadze, George I. Melikadze, Istvan V. Forizs, Sophio G. Vepkhvadze, Marina Sh. Todadze, Elene V. Chikviladze, Ludmila E. Ghlonti


This study is the first attempt to use geochemical techniques to evaluate geothermal reservoir in Georgia. The geographical area of the study is named the Tbilisi geothermal reservoir and belongs to the Sartichala sub-zone of the Adjara-Trialeti folded system of the Lesser Caucasus. Thirteen thermal water samples were taken from existing thermal boreholes on the territory of Tbilisi, additionally one sample of river Legvtakhevi, to be used as cold water component for estimation of reservoir temperature. The samples revealed the majority have Na-K-HCO3 composition compared to just few of them Na-K-Cl-SO4 and Ca-Mg-SO4-Cl. Water-type changes from bicarbonate to Sulfate-Chloride from the West to the East were also observed. Reservoir temperature estimations by silica-enthalpy method is 130 ºC, 163 ºC, 212 ºC. 

The results of this and other current studies manifest the need for further researches and the steps and methodology thereof.


geochemistry, geothermal reservoir, geothermometers, silica-enthalpy mixing method

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