TY  - JOUR
TI  - Hydrochemical characteristics and geothermometry applications of thermal waters in
the Çürüksu Graben, western Turkey
AB  - In this study, we investigate chemical and isotopic characteristics of low-temperature geothermal waters issuing from carbonate
reservoirs in the Çürüksu Graben within the eastern termination of the Büyük Menderes Graben in western Turkey. Temperatures and
pH values of geothermal waters vary from 20.1 to 24.6 ºC and 6.62 to 7.11 and those of cold waters are 17.1 to 19.9 ºC and 6.85 to 7.72, respectively. Geothermal waters are of $Ca-HCO_3$ and $Ca-SO_4$ types whereas cold waters are characterized by these two types and $Mg-HCO_3$as well. $δ^{18}O$ and δD values of samples vary from –9.27‰ to –7.69‰ (VSMOW) and –58.06‰ to –52.2‰ and indicate a
meteoric origin with local recharge. Tritium contents are from 0.12 to 2.17 TU for thermal waters and 0.28 to 4.85 TU for the cold
waters implying relatively longer residence time for the hot waters. Thermal water samples mostly have positive $^{δ13}C$ values (varying
from –0.32‰ to +1.99‰) and carbon in these waters is likely derived from marine limestone or metamorphic $CO_{2}.$ $δ^{34}S$ and $δ^{18}O$ values
of dissolved sulfate in the waters indicate that sulfur originates from dissolution of marine evaporite deposits (e.g., gypsum). Çürüksu
waters are generally oversaturated with respect to calcite, dolomite and quartz but undersaturated with respect to gypsum. Common ion
effect exerted a strong control for the formation of travertine deposits in the area. Chemical and isotopic evaluations indicated that the
diversity in the water chemistry of samples is attributed to a combination of processes including water-rock interaction, ion exchange
and mixing of various types of waters. Çürüksu thermal waters are immature and not in chemical equilibrium with the reservoir
rock. Among the various geothermometers applied to Çürüksu thermal waters, temperatures computed by chalcedony, quartz and CaMg geothermometers are 21–52 ºC, 49–83 ºC and 73–96 ºC, respectively. $HCO_3-SO_4-F$ and anhydrite-chalcedony (quartz) diagrams estimated a temperature range of 63–86 ºC and $δ^{18}O$$(SO_4 -H_2O)$ isotope geothermometer yielded 67–78 ºC.
AU  - Mutlu, Halim
AU  - Gokgoz, Ali
AU  - Akman, Mehmet Ali
DO  - 10.3906/yer-2111-18
PY  - 2022
JO  - Turkish Journal of Earth Sciences
VL  - 31
IS  - 3
SN  - 1300-0985
SP  - 260
EP  - 283
DB  - TRDizin
UR  - http://search/yayin/detay/521994
ER  -