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| Titel |
Pressure tomography for exploring CO2 plume evolution in a deep saline homogeneous aquifer |
| VerfasserIn |
Linwei Hu, Peter Bayer, Peter Alt-Epping, Alexandru Tatomir, Martin Sauter, Ralf Brauchler |
| Konferenz |
EGU General Assembly 2015
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| Medientyp |
Artikel
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| Sprache |
Englisch
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| Digitales Dokument |
PDF |
| Erschienen |
In: GRA - Volume 17 (2015) |
| Datensatznummer |
250107234
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| Publikation (Nr.) |
 EGU/EGU2015-6929.pdf |
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| Zusammenfassung |
| Deep saline aquifers serve as the potential CO2 storage formations due to their often large storage capacity. For characterizing and monitoring CO2 migration in deep saline aquifers, cost-efficient and expressive field methods are required to provide direct insight into the prevailing physical conditions of the subsurface. In our study, we propose an innovative pressure tomography approach to characterize the initial flow properties of the aquifer and the development of CO2 plume based on a virtual homogeneous saline aquifer. Deep CO2 injection has an impact on the flow properties of the CO2 and brine mixture depending on the saturation. Variations of the flow properties, such as hydraulic diffusivity, are considered as indicators for tracking the plume, which can roughly be approximated by a single-phase model. Comparable to seismic tomography experiments, pressure tomography generates streamline patterns by either injecting brine at variable depths (sources) prior to full-scale CO2 injection, or by injecting small amounts of CO2 into the CO2-brine system during later stages of storage. The streamlines are derived by recording the introduced pressure responses at given observation locations (receivers). An eikonal-based pressure tomographical framework allows the quantification of the apparent single-phase or mixed-phase diffusivity of the formation. By applying the inversion at different times and by comparison of the inverted diffusivity tomograms, the evolution of the CO2 plume shape can be monitored temporally in a time-lapse strategy. |
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