 |
| Titel |
Assessment of CO2 discharge in a spring using time-variant stable carbon isotope data as a natural analogue study of CO2 leakage |
| VerfasserIn |
Soonyoung Yu, Gitak Chae, Minki Jo, Jeong-Chan Kim, Seong-Taek Yun |
| Konferenz |
EGU General Assembly 2015
|
| Medientyp |
Artikel
|
| Sprache |
Englisch
|
| Digitales Dokument |
PDF |
| Erschienen |
In: GRA - Volume 17 (2015) |
| Datensatznummer |
250104920
|
| Publikation (Nr.) |
 EGU/EGU2015-4361.pdf |
|
|
|
|
|
| Zusammenfassung |
| CO2-rich springs have been studied as a natural analogue of CO2 leakage through
shallow subsurface environment, as they provide information on the behaviors of CO2
during the leakage from geologic CO2 storage sites. For this study, we monitored the
δ13C values as well as temperature, pH, EC, DO, and alkalinity for a CO2-rich
spring for 48 hours. The water samples (N=47) were collected every hour in stopper
bottles without headspace to avoid the interaction with air and the CO2 degassing.
The δ13C values of total dissolved inorganic carbon (TDIC) in the water samples
were analyzed using a cavity ring-down spectroscopy (CRDS) system (Picarro).
The values of δ13CTDIC, temperature, pH, EC, DO, and alkalinity were in the
range of -9.43 ~ -8.91 o 12.3 ~ 13.2oC, 4.86 ~ 5.02, 186 ~ 189 μS/cm, 1.8
~ 3.4 mg/L, and 0.74 ~ 0.95 meq/L, respectively. The concentrations of TDIC
calculated using pH and alkalinity values were between 22.5 and 34.8 mmol/L.
The δ13CTDIC data imply that dissolved carbon in the spring was derived from a
deep-seated source (i.e., magmatic) that was slightly intermixed with soil CO2. Careful
examination of the time-series variation of measured parameters shows the following
characteristics: 1) the δ13CTDIC values are negatively correlated with pH (r = -0.59) and
positively correlated with TDIC (r = 0.58), and 2) delay times of the change of
pH and alkalinity following the change of δ13CTDIC values are 0 and -3 hours,
respectively; the pH change occurs simultaneously with the change of δ13CTDIC,
while the alkalinity change happens before 3 hours. Our results indicate that the
studied CO2-rich spring is influenced by the intermittent supply of deep-seated
CO2. [Acknowledgment] This work was financially supported by the fundamental
research project of KIGAM and partially by the "Geo-Advanced Innovative Action
(GAIA) Project (2014000530003)" from Korea Ministry of Environment (MOE). |
|
|
|
|
|
|