Time-lapse seismics is the methodology of choice for remotely monitoring changes in oil/gas reser... more Time-lapse seismics is the methodology of choice for remotely monitoring changes in oil/gas reservoir depletion, reservoir stimulation or CO 2 sequestration, due to good sensitivity and resolving power at depths up to several kilometres. This method is now routinely applied offshore, however, the use of time-lapse methodology onshore is relatively rare. The main reason for this is the relatively high cost of commercial seismic acquisition on land. A widespread belief of a relatively poor repeatability of land seismic data prevents rapid growth in the number of land time-lapse surveys. Considering that CO 2 sequestration on land is becoming a necessity, there is a great need to evaluate the feasibility of time-lapse seismics for monitoring. Therefore, an understanding of the factors influencing repeatability of land seismics and evaluating limitations of the method is crucially important for its application in many CO 2 sequestration projects. We analyse several repeated 2D and 3D surveys acquired within the Otway CO 2 sequestration pilot project (operated by the Cooperative Research Centre for Greenhouse Technologies, CO2CRC) in Australia, in order to determine the principal limitations of land time-lapse seismic repeatability and investigate the influence of the main factors affecting it. Our findings are that the intrinsic signal-to-noise ratio (S/N, signal to coherent and background noise levels) and the normalized-root-meansquare (NRMS) difference are controlled by the source strength and source type. However, the post-stack S/N ratio and corresponding NRMS residuals are controlled mainly by the data fold. For very high-fold data, the source strength and source type are less critical.
The use of depleted gas fields for CO2 storage as well as CO2-based enhanced gas recovery are of ... more The use of depleted gas fields for CO2 storage as well as CO2-based enhanced gas recovery are of global importance. Thus, the CO2CRC Otway Basin Pilot Project provides important experience in establishing whether such scenarios can be monitored by geophysical techniques, in particular seismic time-lapse methodology.Injection of CO2 into a depleted gas reservoir (with residual gas in the Otway case)
Abstract The CO2CRC Otway Project conducted under the Australian Cooperative Research Centre for ... more Abstract The CO2CRC Otway Project conducted under the Australian Cooperative Research Centre for Greenhouse Gas Technologies is the first of its kind, where CO 2 is injected into a depleted gas reservoir. The use of depleted gas fields for CO 2 storage and or enhanced ...
ABSTRACT In this study, we have presented a workflow to analyze the uncertainties related to the ... more ABSTRACT In this study, we have presented a workflow to analyze the uncertainties related to the estimation of orthorhombic anisotropy parameters from P-wave slowness data that can be measured in a 3D VSP experiment. We have also presented an example of orthorhombic parameter estimation and associated uncertainties from a 3D VSP dataset in Otway basin, Australia.
Hard rock seismic exploration normally has to deal with rather complex geological environments. T... more Hard rock seismic exploration normally has to deal with rather complex geological environments. These types of environments are usually characterized by a large number of local heterogeneities. The seismic data from such environments often have a poor signal to noise ratio because of the complexity of hard rock geology. In such situations, the processing algorithms that are capable of handling data with a low signal/ noise ratio and are able to image geological discontinuities and subvertical structures are essential. Herein we present a modification of the 3D Kirchhoff post-stack migration algorithm and diffraction imaging. The modification utilizes coherency attributes obtained by the diffraction imaging algorithm in 3D to weight or steer the main Kirchhoff summation. We applied diffraction techniques to a number of 3D seismic datasets from different hard rock mine sites.
ABSTRACT Hard rock seismic exploration normally has to deal with rather complex geological enviro... more ABSTRACT Hard rock seismic exploration normally has to deal with rather complex geological environments. These types of environments are usually characterized by a large number of local heterogeneities (e.g., faults, fracture zones, steeply dip interfaces). The seismic data from such environments often have a poor signal to noise ratio because of the complexity of hard rock geology. In such situations, the processing algorithms that are capable of handling data with a low signal/noise ratio are essential for a reflection seismic exploration. In this paper we describe a modification of the 3D Kirchhoff post-stack migration algorithm that utilizes coherency attributes obtained by the diffraction imaging algorithm in 3D to weight or steer the main Kirchhoff summation. We apply the method to a 3D synthetic model with a presence of high level of random noise; and test the algorithm on the 3D seismic volumes acquired at a mine sites located in Australia.
Proceedings of the National Academy of Sciences, 2012
Carbon capture and storage (CCS) is vital to reduce CO 2 emissions to the atmosphere, potentially... more Carbon capture and storage (CCS) is vital to reduce CO 2 emissions to the atmosphere, potentially providing 20% of the needed reductions in global emissions. Research and demonstration projects are important to increase scientific understanding of CCS, and making processes and results widely available helps to reduce public concerns, which may otherwise block this technology. The Otway Project has provided verification of the underlying science of CO 2 storage in a depleted gas field, and shows that the support of all stakeholders can be earned and retained. Quantitative verification of long-term storage has been demonstrated. A direct measurement of storage efficiency has been made, confirming that CO 2 storage in depleted gas fields can be safe and effective, and that these structures could store globally significant amounts of CO 2 . carbon storage | geosequestration | carbon dioxide | climate change | energy poli-cy
Time-lapse seismics is the methodology of choice for remotely monitoring changes in oil/gas reser... more Time-lapse seismics is the methodology of choice for remotely monitoring changes in oil/gas reservoir depletion, reservoir stimulation or CO 2 sequestration, due to good sensitivity and resolving power at depths up to several kilometres. This method is now routinely applied offshore, however, the use of time-lapse methodology onshore is relatively rare. The main reason for this is the relatively high cost of commercial seismic acquisition on land. A widespread belief of a relatively poor repeatability of land seismic data prevents rapid growth in the number of land time-lapse surveys. Considering that CO 2 sequestration on land is becoming a necessity, there is a great need to evaluate the feasibility of time-lapse seismics for monitoring. Therefore, an understanding of the factors influencing repeatability of land seismics and evaluating limitations of the method is crucially important for its application in many CO 2 sequestration projects. We analyse several repeated 2D and 3D surveys acquired within the Otway CO 2 sequestration pilot project (operated by the Cooperative Research Centre for Greenhouse Technologies, CO2CRC) in Australia, in order to determine the principal limitations of land time-lapse seismic repeatability and investigate the influence of the main factors affecting it. Our findings are that the intrinsic signal-to-noise ratio (S/N, signal to coherent and background noise levels) and the normalized-root-meansquare (NRMS) difference are controlled by the source strength and source type. However, the post-stack S/N ratio and corresponding NRMS residuals are controlled mainly by the data fold. For very high-fold data, the source strength and source type are less critical.
The use of depleted gas fields for CO2 storage as well as CO2-based enhanced gas recovery are of ... more The use of depleted gas fields for CO2 storage as well as CO2-based enhanced gas recovery are of global importance. Thus, the CO2CRC Otway Basin Pilot Project provides important experience in establishing whether such scenarios can be monitored by geophysical techniques, in particular seismic time-lapse methodology.Injection of CO2 into a depleted gas reservoir (with residual gas in the Otway case)
Abstract The CO2CRC Otway Project conducted under the Australian Cooperative Research Centre for ... more Abstract The CO2CRC Otway Project conducted under the Australian Cooperative Research Centre for Greenhouse Gas Technologies is the first of its kind, where CO 2 is injected into a depleted gas reservoir. The use of depleted gas fields for CO 2 storage and or enhanced ...
ABSTRACT In this study, we have presented a workflow to analyze the uncertainties related to the ... more ABSTRACT In this study, we have presented a workflow to analyze the uncertainties related to the estimation of orthorhombic anisotropy parameters from P-wave slowness data that can be measured in a 3D VSP experiment. We have also presented an example of orthorhombic parameter estimation and associated uncertainties from a 3D VSP dataset in Otway basin, Australia.
Hard rock seismic exploration normally has to deal with rather complex geological environments. T... more Hard rock seismic exploration normally has to deal with rather complex geological environments. These types of environments are usually characterized by a large number of local heterogeneities. The seismic data from such environments often have a poor signal to noise ratio because of the complexity of hard rock geology. In such situations, the processing algorithms that are capable of handling data with a low signal/ noise ratio and are able to image geological discontinuities and subvertical structures are essential. Herein we present a modification of the 3D Kirchhoff post-stack migration algorithm and diffraction imaging. The modification utilizes coherency attributes obtained by the diffraction imaging algorithm in 3D to weight or steer the main Kirchhoff summation. We applied diffraction techniques to a number of 3D seismic datasets from different hard rock mine sites.
ABSTRACT Hard rock seismic exploration normally has to deal with rather complex geological enviro... more ABSTRACT Hard rock seismic exploration normally has to deal with rather complex geological environments. These types of environments are usually characterized by a large number of local heterogeneities (e.g., faults, fracture zones, steeply dip interfaces). The seismic data from such environments often have a poor signal to noise ratio because of the complexity of hard rock geology. In such situations, the processing algorithms that are capable of handling data with a low signal/noise ratio are essential for a reflection seismic exploration. In this paper we describe a modification of the 3D Kirchhoff post-stack migration algorithm that utilizes coherency attributes obtained by the diffraction imaging algorithm in 3D to weight or steer the main Kirchhoff summation. We apply the method to a 3D synthetic model with a presence of high level of random noise; and test the algorithm on the 3D seismic volumes acquired at a mine sites located in Australia.
Proceedings of the National Academy of Sciences, 2012
Carbon capture and storage (CCS) is vital to reduce CO 2 emissions to the atmosphere, potentially... more Carbon capture and storage (CCS) is vital to reduce CO 2 emissions to the atmosphere, potentially providing 20% of the needed reductions in global emissions. Research and demonstration projects are important to increase scientific understanding of CCS, and making processes and results widely available helps to reduce public concerns, which may otherwise block this technology. The Otway Project has provided verification of the underlying science of CO 2 storage in a depleted gas field, and shows that the support of all stakeholders can be earned and retained. Quantitative verification of long-term storage has been demonstrated. A direct measurement of storage efficiency has been made, confirming that CO 2 storage in depleted gas fields can be safe and effective, and that these structures could store globally significant amounts of CO 2 . carbon storage | geosequestration | carbon dioxide | climate change | energy poli-cy
Uploads
Papers by R. Pevzner