Geochemical characterization of geothermal systems in Turkey as natural analogues for geological storage of Co2/

Elidemir, Sanem
To mitigate the unfavourable effect of CO2 emission on global warming and climate change, geological storage of CO2 is currently regarded to be one of the major strategies. Deep saline formations constitute one of the alternative reservoirs for hosting the injected CO2 and the information about the behaviour of these reservoirs is provided via the studies of natural analogues. This thesis is concerned with the geothermal systems of Turkey as natural analogues for CO2 storage sites and the evaluation of their geochemical characteristics in terms of possible hydrogeochemical processes involved in CO2 storage. For the selected geothermal fields from western, eastern and northern Anatolia, the hydrogeochemical processes and potential trapping mechanisms controlling the systems are determined with the assistance of various geochemical approaches including the geochemical characterization of the system, speciation-solubility calculations, estimation of relative contribution of carbonate and sulphate minerals to the system, and modelling studies (such as inverse modelling, dedolomitization modelling) depending on the behaviour of the field. The results lead to the recognition of three different groups of geothermal systems with respect to the dominant trapping mechanisms: mineral trapping, solubility trapping and mineral ± solubility trapping. In some of the fields from western Anatolia, mineral trapping seems to be the major mechanism, while the others show the effects of both mineral and solubility trapping; a special mechanism named dedolomitization is also identified for Emet geothermal field. For eastern Anatolian fields, and for the fields located along the North Anatolian Fault Zone, solubility trapping is the dominant mechanism.


Geochemical characterization of geothermal systems in western Anatolia (Turkey): implications for CO2 trapping mechanisms in prospective CO2-EGS sites
Elidemir, Sanem; Güleç, Nilgün Türkan (2018-02-01)
Geological storage of CO2 is currently regarded as one of the major strategies to mitigate the increasing CO2 concentrations in the atmosphere due to anthropogenic emissions from large-scale point sources. Enhanced geothermal systems (EGS) are a novel concept in which CO2 is used as a working fluid to increase energy recovery, combined with its subsurface storage. In this study, the geothermal systems of western Anatolia are considered as potential sites for EGS, and the published hydrogeochemical data rele...
Geochemical modeling of CO2-water-rock interaction in indonesian geothermal fields for a possible future carbon capture and storage project
Utomo, Gagas Pambudi; Yılmaz, Koray K.; Department of Geological Engineering (2019)
The rise of CO2 concentration in Earth’s atmosphere from anthropogenic emissions is the main cause of global warming and climate change. Carbon Capture and Storage (CCS) is considered as an effective method to reduce such emission. CCS can be performed in various sites including geothermal reservoirs. This study is concerned with geochemical modeling of CO2-water-rock interaction for a possible future CCS project in Indonesian geothermal fields, namely Ungaran, Baturaden, Dieng and Awibengkok. The modeling ...
Geothermal systems as natural analogues for geological storage of CO2: implications for trapping mechanisms from hydrogeochemistry of western Anatolian fluids (Turkey).
Elidemir, Sanem; Güleç, Nilgün Türkan (2017-08-13)
Carbon Capture and Storage (CCS) is a widely accepted strategy to reduce the unfavourable effects of CO2 emission on global warming. Natural analogues provide a valuable source for the investigation of the behaviour of CO2 at subsurface after its injection. Geothermal fields, representing deep saline aquifers, are considered as natural analogues for CO2 storage sites. This study focuses on the geothermal systems of western Anatolia (Turkey) to investigate the possible CO2-fixation mechanisms by using the pu...
Estimation of carbon footprint: a case study for Middle East Technical University
Turanlı, Ayşe Merve; Mehmetoğlu, Mustafa Tanju; Okandan, Ender; Department of Petroleum and Natural Gas Engineering (2015)
As the amount of the greenhouse gas emission increases, its effect on climate change becomes accordingly important. This fact is proved by the measurements conducted by NASA in terms of mole fraction of CO2. After 1950’s due to rapid rise in industrial activity of post-industrial revolution period, CO2 amount in the air increased constantly. Atmospheric concentration of CO2 increases at an accelerating rate . In year 2014, the CO2 emission value had reached 398.78 ppm. This increase led the investigators to...
Sustainability Assessments of Urban Railway Systems: Case Study Evaluations in Turkey
YÜKSEL, MÜGE; Tanyer, Ali Murat; Pekeriçli, Mehmet Koray (Springer, 2019-01-01)
There are ongoing efforts to control global warming via reducing CO2 emissions, which are mostly based on human activities. Through life cycle assessment (LCA) carbon footprint (CFP) calculations provide a clear picture of embodied carbon (EC). In this study, the significance of EC estimation and reduction for railway projects are explored. The main motivation is having applicable sustainability strategies for railway systems in Turkey. Since there is no certification system, range or database, these effort...
Citation Formats
S. Elidemir, “Geochemical characterization of geothermal systems in Turkey as natural analogues for geological storage of Co2/,” M.S. - Master of Science, Middle East Technical University, 2014.