Imaging of CO{sub 2} injection during an enhanced-oil-recovery experiment
A series of time-lapse seismic cross well and single well experiments were conducted in a diatomite reservoir to monitor the injection of CO{sub 2} into a hydrofracture zone, using P- and S-wave data. During the first phase the set of seismic experiments were conducted after the injection of water into the hydrofrac-zone. The set of seismic experiments was repeated after a time period of 7 months during which CO{sub 2} was injected into the hydrofractured zone. The issues to be addressed ranged from the detectability of the geologic structure in the diatomic reservoir to the detectability of CO{sub 2} within the hydrofracture. During the pre-injection experiment, the P-wave velocities exhibited relatively low values between 1700-1900 m/s, which decreased to 1600-1800 m/s during the post-injection phase (-5 percent). The analysis of the pre-injection S-wave data revealed slow S-wave velocities between 600-800 m/s, while the post-injection data revealed velocities between 500-700 m/s (-6 percent). These velocity estimates produced high Poisson ratios between 0.36 and 0.46 for this highly porous ({approx} 50 percent) material. Differencing post- and pre-injection data revealed an increase in Poisson ratio of up to 5 percent. Both, velocity and Poisson estimates indicate the dissolution of CO{sub 2} in the liquid phase of the reservoir accompanied by a pore-pressure increase. The results of the cross well experiments were corroborated by single well data and laboratory measurements on core data.
- Research Organization:
- Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States)
- Sponsoring Organization:
- USDOE Director, Office of Basic Energy Sciences, Division of Engineering and Geosciences, GEO-SEQ project, DOE National Energy Technology Laboratory, DE-AC03-76SF00098; Chevron USA Production Co., National Petroleum Office, DE-FC22-95BC14938, Class III Field Demonstration Project (US)
- DOE Contract Number:
- AC03-76SF00098
- OSTI ID:
- 816368
- Report Number(s):
- LBNL-52626; R&D Project: G20401; TRN: US200320%%442
- Resource Relation:
- Conference: Underground Injection Science and Technology Symposium, Berkeley, CA (US), 10/22/2003--10/25/2003; Other Information: PBD: 29 Apr 2003
- Country of Publication:
- United States
- Language:
- English
Similar Records
Small Scale Field Test Demonstrating CO2 Sequestration In Arbuckle Saline Aquifer And By CO2-Eor At Wellington Field, Sumner County, Kansas
Passive characterization of hydrofracture properties using signals from the hydraulic pumps