The origin of hydrogen sulphide found in abnormally saline groundwaters in Kuwait City, Kuwait

• Published in: Arabian journal of geosciences Vol. 14; no. 14
• Main Authors: Al-Hajeri, Mubarak Matlak, Amer, Aimen
• Format: Journal Article
• Language: English
• Published: Cham Springer International Publishing 01-07-2021; Springer Nature B.V
• Subjects: Anthropogenic factors; Carbon dioxide; Earth and Environmental Science; Earth science; Earth Sciences; Fluids; Geochemistry; Geographical variations; Geological faults; Groundwater; High temperature; Hydrogen sulfide; Hydrogen sulphide; Hydrologic data; Isotopes; Low temperature; Oil reservoirs; Original Paper; Sulfate reduction; Sulfates; Sulphate reduction; Sulphides; Tectonics; Water chemistry; Water sampling; Kuwait; H2S; Upfault water migration; Kuwait city groundwater; Kuwait; Sulphur isotopes; Groundwater salinity
• ISSN: 1866-7511; 1866-7538
• DOI: 10.1007/s12517-021-07321-x

The paper presents a qualitative assessment water geochemistry study to understand the deep non-anthropogenic origin of dissolved H
2
S in anomalously abnormal saline groundwaters in Kuwait City. The groundwater samples show geographical variation in water chemistry, salinity, CO
2
and H
2
S concentrations and δ
34
S isotope data. The variation was found to be controlled by the proximity to the abandoned Medina Field. Three geographical areas in Kuwait City with different groundwater properties were identified: Area-A with very high H
2
S concentration (> 100 mg/l); Area-B with moderate H
2
S concentration (50–100 mg/l) and Area-C with low H
2
S concentration (< 50 mg/l). The δ
34
S isotope data of dissolved H
2
S in the groundwater samples showed a range of −8.9 to −12.9‰. The variation of δ
34
S values indicate the origin of H
2
S sourced from mixing of low-temperature sulphate reduction (BSR) with high-temperature thermochemical sulphate reduction (TSR) fluids migrated up-fault from deeper and hotter oil reservoirs through reactivated NE-SW deep-seated faults during recent tectonic events.