Hydrogeochemical Characterization of Leaking, Carbon Dioxide—Charged Fault Zones in East-Central Utah, With Implications for Geological Carbon Storage

Authors

Jason E. Heath, Utah State University
Thomas E. Lachmar, Utah State UniversityFollow
James P. Evans, Utah State UniversityFollow
Peter T. Kolesar, Utah State UniversityFollow
Anthony P. Williams

Document Type

Contribution to Book

Journal/Book Title/Conference

Carbon Sequestration and Its Role in the Global Carbon Cycle

Volume

183

Publisher

American Geophysical Union

Publication Date

2009

First Page

147

Last Page

158

Abstract

We examined a natural, CO₂-charged subsurface system located near two fault zones in East-Central Utah that is analogous to engineered sequestration sites. Geologic information and geochemical and isotopic data from water and gas samples were used to develop a conceptual model of the flow system. This flow-system description indicates that CO₂ from a depth >800 m migrates upward through a system of shallower, stacked aquifers. The geologic structure in the area serves to focus the CO₂-rich waters at the location of a faulted, anticlinal trap. The faults in the area impede horizontal flow but allow vertical leakage through thick, low-permeability formations. An important implication from this CO₂-sequestration analog is that leakages occur along discrete flow paths in the subsurface; thus, in sequestration scenarios, detailed understanding of discrete flow paths will be necessary. Another implication is that groundwater can transport a significant amount of CO₂, and thus, sampling groundwater chemistries from wells may be a better way to identify leakages than using monitoring techniques at the surface. Finally, even though mineralization occurs during CO₂ leakage to the surface, self-sealing has not occurred at this natural analog and may not occur at engineered sequestration sites.

Comments

Originally published by the American Geophysical Union. Book available for purchase through remote link. Chapter fulltext not available online.

Recommended Citation

Heath, J. E., Lachmar, T. E., Kolesar, P. T., and Evans, J. P., Hydrogeochemical Characterization of Leaking, Carbon Dioxide—Charged Fault Zones in East-Central Utah, With Implications for Geological Carbon Storage, in: McPherson, B. J., Sundquist, E., eds., Carbon Sequestration and Its Role in the Global Carbon Cycle AGU Geophysical Monograph Series 183, p. 147- 158.