Passive seismic reflection interferometry: A case study from the Aquistore CO2 storage site, Saskatchewan, Canada

Seismic reflection interferometry has recently been tested in a few resource-exploration applications. We have evaluated passive seismic interferometry results for data from the Aquistore [Formula: see text] storage site, Saskatchewan, Canada, with the objective of testing the method’s ability to image the subsurface geology and its potential for time-lapse imaging. We analyzed passive seismic data recorded along two perpendicular geophone lines for two time periods that include 23 days in June 2014 and 13 days in February 2015. Beam-forming analysis showed that a nearby power plant is the dominant source of ambient noise. We retrieved virtual shot gathers not only by correlating long noise panels (1 h) for both recording periods, but also by correlating shorter noise panels (10 s) from two days of each recording period. We applied illumination diagnosis to the noise panels from the two chosen days for each period to help suppress the surface waves. Comparisons of the common-midpoints stacked sections, resulting from the virtual shot gathers, with colocated active-source images and log-based synthetic seismograms showed that the best ambient-noise images were obtained for the longest recording periods. The application of illumination diagnosis revealed that only a small percentage of the noise panels are dominated by body waves. Thus, images formed using only this subset of noise panels failed to improve the images obtained from the 23 and 13 days of noise recording. To evaluate the passive images, we performed log-based correlations that showed moderate correlation ranging from approximately 0.5–0.65 in the two-way time range of 0.8–1.5 s. For the 13 to 23 days of noise used in our analysis, the resulting images at the reservoir depth of 3200 m or [Formula: see text] are unlikely to be suitable for time-lapse imaging at this site. This is most likely due to the limited directional illumination and dominance of surface-wave noise.

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Passive Seismic Ambient Noise Correlation: An Example from the Ketzin Experimental CO2 Storage Site, Germany

Energy Procedia ◽

10.1016/j.egypro.2014.10.353 ◽

2014 ◽

Vol 59 ◽

pp. 90-96 ◽

Cited By ~ 2

Author(s):

Fengjiao Zhang ◽

Christopher Juhlin ◽

Daniel Sopher

Keyword(s):

Ambient Noise ◽

Co2 Storage ◽

Noise Correlation ◽

Storage Site ◽

Seismic Ambient Noise ◽

Passive Seismic

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Borehole seismic methods for geologic CO2 storage monitoring

The Leading Edge ◽

10.1190/tle40060434.1 ◽

2021 ◽

Vol 40 (6) ◽

pp. 434-441

Author(s):

Don White ◽

Thomas M. Daley ◽

Björn Paulsson ◽

William Harbert

Keyword(s):

Co2 Storage ◽

Geophysical Methods ◽

Time Lapse ◽

Microseismic Monitoring ◽

Seismic Methods ◽

Geologic Co2 Storage ◽

Subsurface Monitoring ◽

Borehole Seismic ◽

Time Lapse Imaging

Borehole geophysical methods are a key component of subsurface monitoring of geologic CO2 storage sites because boreholes form a locus where geophysical measurements can be compared directly with the controlling geology. Borehole seismic methods, including intrawell, crosswell, and surface-to-borehole acquisition, are useful for site characterization, surface seismic calibration, 2D/3D time-lapse imaging, and microseismic monitoring. Here, we review the most common applications of borehole seismic methods in the context of storage monitoring and consider the role that detailed geophysical simulations can play in answering questions that arise when designing monitoring plans. Case study examples are included from the multitude of CO2 monitoring projects that have demonstrated the utility of borehole seismic methods for this purpose over the last 20 years.

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Assessment of 4D seismic repeatability and CO2 detection limits using a sparse permanent land array at the Aquistore CO2 storage site

Geophysics ◽

10.1190/geo2014-0201.1 ◽

2015 ◽

Vol 80 (2) ◽

pp. WA1-WA13 ◽

Cited By ~ 43

Author(s):

Lisa A. N. Roach ◽

Donald J. White ◽

Brian Roberts

Keyword(s):

Co2 Storage ◽

Time Lapse ◽

Data Sets ◽

Storage Site ◽

Processing Sequence ◽

Time Migration ◽

Receiver Array ◽

Co2 Detection ◽

4D Seismic ◽

The Impact

Two 3D time-lapse seismic surveys were acquired in 2012 and 2013 at the Aquistore [Formula: see text] storage site prior to the start of [Formula: see text] injection. Using these surveys, we determined the background time-lapse noise at the site and assessed the feasibility of using a sparse areal permanent receiver array as a monitoring tool. Applying a standard processing sequence to these data, we adequately imaged the reservoir at 3150–3350 m depth. Evaluation of the impact of each processing step on the repeatability revealed a general monotonic increase in similarity between the data sets as a function of processing. The prestack processing sequence reduced the normalized root mean squared difference (nrms) from 1.13 between the raw stacks to 0.13 after poststack time migration. The postmigration cross-equalization sequence further reduced the global nrms to 0.07. A simulation of the changes in seismic response due to a range of [Formula: see text] injection scenarios suggested that [Formula: see text] was detectable within the reservoir at the Aquistore site provided that zones of greater thickness than 6–13 m have reached [Formula: see text] saturations of greater than 5%.

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Comparison of seismic interferometry techniques for the retrieval of seismic body waves in CO2 sequestration monitoring

Journal of Geophysics and Engineering ◽

10.1093/jge/gxz079 ◽

2019 ◽

Vol 16 (6) ◽

pp. 1094-1115

Author(s):

Haitao Cao ◽

Roohollah Askari

Keyword(s):

Co2 Sequestration ◽

Field Data ◽

Cross Correlation ◽

Time Lapse ◽

Body Waves ◽

Seismic Interferometry ◽

Storage Site ◽

Phase Information ◽

Wave Data ◽

The Cross

Abstract Ambient noise seismic interferometry performed by cross-correlation has been proven to be a potential cost-effective technique for geological studies. To improve the resolution of images created by interferometry, additional techniques using deconvolution and cross-coherence have been introduced. While all three methods have previously been evaluated using surface wave data for shear-wave imaging of the near surface, comparatively little study has been devoted to assess the three methods for the retrieval of body waves in reflection surveys for time-lapse application. Moreover, although the application of seismic interferometry to CO2 sequestration by cross-correlation has been investigated by many researchers, to our knowledge, similar time-lapse studies have not been conducted using deconvolution and cross-coherence methods. We evaluate the three methods of cross-correlation, deconvolution and cross-coherence for the retrieval of phase information contained in virtual seismic records by applying seismic interferometry to synthetic data, using a model reservoir before and after CO2 injection. By examining two approaches of regularization and smoothing factors to suppress spurious reflection events observed on the deconvolution and cross-coherence results, we note that both approaches provide similar results. We investigate noise effects by adding random noise independently at each geophone. Finally, we apply these techniques to field data recorded near the CO2 storage site in Ketzin, Germany. For both our numerical and field data studies, we find that the cross-coherence technique retrieves the phase information of body-wave data more effectively than the cross-correlation and deconvolution techniques, and is less sensitive to uncorrelated noise from shallow sources.

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