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Ghassan Alregib - One of the best experts on this subject based on the ideXlab platform.
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noise robust detection and tracking of Salt Domes in postmigrated volumes using texture tensors and subspace learning
arXiv: Image and Video Processing, 2018Co-Authors: Zhen Wang, Zhiling Long, Tamir Hegazy, Ghassan AlregibAbstract:The identification of Salt Dome boundaries in migrated seismic data volumes is important for locating petroleum reservoirs. The presence of noise in the data makes computer-aided Salt Dome interpretation even more challenging. In this paper, we develop noise-robust algorithms that can label boundaries of Salt Domes both effectively and efficiently. Our research is twofold. First, we utilize a texture-based gradient to accomplish Salt Dome detection. We show that by employing a dissimilarity measure based on two-dimensional (2D) discrete Fourier transform (DFT), the algorithm is capable of efficiently detecting Salt Dome boundaries with accuracy. At the same time, our analysis shows that the proposed algorithm is robust to noise. Once the detection is performed for an initial 2D seismic section, we propose to track the initial boundaries through the data volume to accomplish an efficient labeling process by avoiding parameters tuning that would have been necessary if detection had been performed for every seismic section. The tracking process involves a tensor-based subspace learning process, in which we build texture tensors using patches from different seismic sections. To accommodate noise components with various levels in a texture tensor, we employ noise-adjusted principal component analysis (NA-PCA), so that principal components corresponding to greater signal-to-noise ratio values may be selected for tracking. We validate our detection and tracking algorithms through experiments using seismic datasets acquired from Netherland offshore F3 block in the North Sea with very encouraging results.
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a texture based interpretation workflow with application to delineating Salt Domes
Interpretation, 2017Co-Authors: Muhammad Amir Shafiq, Ghassan Alregib, Zhen Wang, Asjad Amin, M DericheAbstract:AbstractWe propose a texture-based interpretation workflow and apply it to delineate Salt Domes in 3D migrated seismic volumes. First, we compute an attribute map using a novel seismic attribute, 3D gradient of textures (3D-GoT), which measures the dissimilarity between neighboring cubes around each voxel in a seismic volume across the time or depth, crossline, and inline directions. To evaluate the texture dissimilarity, we introduce five 3D perceptual and nonperceptual dissimilarity functions. Second, we apply a global threshold on the 3D-GoT volume to yield a binary volume and demonstrate its effects on Salt-Dome delineation using objective evaluation measures such as receiver operating characteristic curves and the areas under the curves. Third, with an initial seed point selected inside the binary volume, we use a 3D region growing method to capture a Salt body. For an automated 3D region growing, we adopt a tensor-based automatic seed point selection method. Finally, we apply morphological postproce...
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noise robust detection and tracking of Salt Domes in postmigrated volumes using texture tensors and subspace learning
Geophysics, 2015Co-Authors: Zhen Wang, Zhiling Long, Tamir Hegazy, Ghassan AlregibAbstract:ABSTRACTThe identification of Salt-Dome boundaries in migrated seismic data volumes is important for locating petroleum reservoirs. The presence of noise in the data makes computer-aided Salt-Dome interpretation even more challenging. We have developed noise-robust algorithms that could label boundaries of Salt Domes effectively and efficiently. Our research is twofold. First, we used a texture-based gradient to accomplish Salt-Dome detection. We found that by using a dissimilarity measure based on the 2D discrete Fourier transform, the algorithm was capable of efficiently detecting Salt-Dome boundaries with accuracy. At the same time, our analysis determined that the proposed algorithm was robust to noise. Once the detection is performed for an initial 2D seismic section, we track the initial boundaries through the data volume to accomplish an efficient labeling process by avoiding the parameter tuning that would have been necessary if detection had been performed for every seismic section. The tracking ...
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Tensor-based subspace learning for tracking Salt-Dome boundaries
2015 IEEE International Conference on Image Processing (ICIP), 2015Co-Authors: Zhen Wang, Zhiling Long, Ghassan AlregibAbstract:The exploration of petroleum reservoirs has a close relationship with the identification of Salt Domes. To efficiently interpret Salt-Dome structures, in this paper, we propose a method that tracks Salt-Dome boundaries through seismic volumes using a tensor-based subspace learning algorithm. We build texture tensors by classifying image patches acquired along the boundary regions of seismic sections and contrast maps. With features extracted from the subspaces of texture tensors, we can identify tracked points in neighboring sections and label Salt-Dome boundaries by optimally connecting these points. Experimental results show that the proposed method outperforms the state-of-the-art Salt-Dome detection method by employing texture information and tensor-based analysis.
Douglas S Dreger - One of the best experts on this subject based on the ideXlab platform.
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moment tensor inversion of seismic events associated with the sinkhole at napoleonville Salt Dome louisiana
Bulletin of the Seismological Society of America, 2014Co-Authors: Avinash Nayak, Douglas S DregerAbstract:Abstract The formation of a large sinkhole at the Napoleonville Salt Dome, Assumption Parish, Louisiana, in August 2012 was accompanied by a rich sequence of complex seismic events. We implemented a grid‐search approach for automatic detection, location, and full moment tensor (MT) inversion of these events using 0.1–0.2 Hz displacement waveforms and 1D velocity models for the Salt Dome and the surrounding sedimentary strata. We were able to detect 62 events, with a 70% variance reduction (VR) detection threshold, during the one‐day period (19:00 hours, 1 August to 19:00 hours, 2 August, 2012) just before the discovery of the sinkhole. The source mechanisms of these events show large isotropic volume‐increase components (61%–82%), with magnitudes varying from M w 1.3 to 1.6 and good waveform fits (71%–86% VR). Locations are well constrained to an approximate depth of 470 m at the western edge of the Salt Dome, close to the sinkhole. For one representative event, the large volume‐increase component in the full MT solution is statistically significant over the deviatoric MT solution and stable with respect to: (1) the velocity models and stations used in the inversion, and (2) the uncertainties in the hypocenter and the MT solution itself. The network sensitivity solution computed for this event using both waveforms and P ‐wave first motion polarities provides greater confidence in the dominantly explosive source mechanism, which can be attributed to high‐pressure flow of natural gas or gas–water mixture through the disturbed rock zone below the sinkhole or pre‐existing zones of weaknesses in the source region. Online Material: Figures showing Q sensitivity, spatial distribution of moment tensor solutions, waveform fits from inversion and 1D models, and tables of the velocity model and event catalog.
Zhen Wang - One of the best experts on this subject based on the ideXlab platform.
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noise robust detection and tracking of Salt Domes in postmigrated volumes using texture tensors and subspace learning
arXiv: Image and Video Processing, 2018Co-Authors: Zhen Wang, Zhiling Long, Tamir Hegazy, Ghassan AlregibAbstract:The identification of Salt Dome boundaries in migrated seismic data volumes is important for locating petroleum reservoirs. The presence of noise in the data makes computer-aided Salt Dome interpretation even more challenging. In this paper, we develop noise-robust algorithms that can label boundaries of Salt Domes both effectively and efficiently. Our research is twofold. First, we utilize a texture-based gradient to accomplish Salt Dome detection. We show that by employing a dissimilarity measure based on two-dimensional (2D) discrete Fourier transform (DFT), the algorithm is capable of efficiently detecting Salt Dome boundaries with accuracy. At the same time, our analysis shows that the proposed algorithm is robust to noise. Once the detection is performed for an initial 2D seismic section, we propose to track the initial boundaries through the data volume to accomplish an efficient labeling process by avoiding parameters tuning that would have been necessary if detection had been performed for every seismic section. The tracking process involves a tensor-based subspace learning process, in which we build texture tensors using patches from different seismic sections. To accommodate noise components with various levels in a texture tensor, we employ noise-adjusted principal component analysis (NA-PCA), so that principal components corresponding to greater signal-to-noise ratio values may be selected for tracking. We validate our detection and tracking algorithms through experiments using seismic datasets acquired from Netherland offshore F3 block in the North Sea with very encouraging results.
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a texture based interpretation workflow with application to delineating Salt Domes
Interpretation, 2017Co-Authors: Muhammad Amir Shafiq, Ghassan Alregib, Zhen Wang, Asjad Amin, M DericheAbstract:AbstractWe propose a texture-based interpretation workflow and apply it to delineate Salt Domes in 3D migrated seismic volumes. First, we compute an attribute map using a novel seismic attribute, 3D gradient of textures (3D-GoT), which measures the dissimilarity between neighboring cubes around each voxel in a seismic volume across the time or depth, crossline, and inline directions. To evaluate the texture dissimilarity, we introduce five 3D perceptual and nonperceptual dissimilarity functions. Second, we apply a global threshold on the 3D-GoT volume to yield a binary volume and demonstrate its effects on Salt-Dome delineation using objective evaluation measures such as receiver operating characteristic curves and the areas under the curves. Third, with an initial seed point selected inside the binary volume, we use a 3D region growing method to capture a Salt body. For an automated 3D region growing, we adopt a tensor-based automatic seed point selection method. Finally, we apply morphological postproce...
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noise robust detection and tracking of Salt Domes in postmigrated volumes using texture tensors and subspace learning
Geophysics, 2015Co-Authors: Zhen Wang, Zhiling Long, Tamir Hegazy, Ghassan AlregibAbstract:ABSTRACTThe identification of Salt-Dome boundaries in migrated seismic data volumes is important for locating petroleum reservoirs. The presence of noise in the data makes computer-aided Salt-Dome interpretation even more challenging. We have developed noise-robust algorithms that could label boundaries of Salt Domes effectively and efficiently. Our research is twofold. First, we used a texture-based gradient to accomplish Salt-Dome detection. We found that by using a dissimilarity measure based on the 2D discrete Fourier transform, the algorithm was capable of efficiently detecting Salt-Dome boundaries with accuracy. At the same time, our analysis determined that the proposed algorithm was robust to noise. Once the detection is performed for an initial 2D seismic section, we track the initial boundaries through the data volume to accomplish an efficient labeling process by avoiding the parameter tuning that would have been necessary if detection had been performed for every seismic section. The tracking ...
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Tensor-based subspace learning for tracking Salt-Dome boundaries
2015 IEEE International Conference on Image Processing (ICIP), 2015Co-Authors: Zhen Wang, Zhiling Long, Ghassan AlregibAbstract:The exploration of petroleum reservoirs has a close relationship with the identification of Salt Domes. To efficiently interpret Salt-Dome structures, in this paper, we propose a method that tracks Salt-Dome boundaries through seismic volumes using a tensor-based subspace learning algorithm. We build texture tensors by classifying image patches acquired along the boundary regions of seismic sections and contrast maps. With features extracted from the subspaces of texture tensors, we can identify tracked points in neighboring sections and label Salt-Dome boundaries by optimally connecting these points. Experimental results show that the proposed method outperforms the state-of-the-art Salt-Dome detection method by employing texture information and tensor-based analysis.
J.t. Neal - One of the best experts on this subject based on the ideXlab platform.
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mine induced sinkholes over the u s strategic petroleum reserve spr storage facility at weeks island louisiana geological mitigation and environmental monitoring
6. multidisciplinary conference on sinkholes and the engineering and environmental impacts of Karst Springfield MO (United States) 6-9 Apr 1997, 1997Co-Authors: J.t. NealAbstract:A sinkhole formed over the former Salt mine used for crude oil storage by the U.S. Strategic Petroleum Reserve at Weeks Island, Louisiana. This created a dilemma because in-mine grouting was not possible, and external grouting, although possible, was impractical. However, environmental protection during oil withdrawal and facility decommissioning was considered critical and alternative solutions were essential. Mitigation of, the sinkhole growth over the Salt mine was accomplished by injecting saturated brine directly into the sinkhole throat, and by constructing a cylindrical freeze curtain around and into the dissolution orifice at the top of the Salt Dome. These measures vastly reduced the threat of major surface collapse around the sinkhole during oil transfer and subsequent brine backfill. The greater bulk of the crude oil was removed from the mine during 1995-6. Final skimming operations will remove residual oil trapped in low spots, concurrent with initiating backfill of the mine with saturated brine. Environmental monitoring during 1995-9 will assure that environmental surety is achieved.
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summary of events and geotechnical factors leading to decommissioning of the strategic petroleum reserve spr facility at weeks island louisiana
Other Information: PBD: Oct 1996, 1996Co-Authors: J.t. Neal, S.j. Bauer, B L EhgartnerAbstract:A sinkhole discovered over the edge of the Strategic Petroleum Reserve storage facility at Weeks Island Salt Dome, Louisiana, led to decommissioning the site during 1995--1998, following extensive diagnostics in 1994. The sinkhole resulted from mine-induced fractures in the Salt which took may years to develop, eventually causing fresh water to leak into the storage chamber and dissolve the overlying Salt, thus causing overburden collapse into the void. Prior to initiating the oil removal, a freeze wall was constructed at depth around the sinkhole in 1995 to prevent water inflow; a freeze plug will remain in place until the mine is backfilled with brine in 1997--8, and stability is reached. Residual oil will be removed; environmental monitoring has been initiated and will continue until the facility is completely plugged and abandoned, and environmental surety is achieved.
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strategic petroleum reserve spr additional geologic site characterization studies bryan mound Salt Dome texas
1994Co-Authors: J.t. Neal, T.r. Magorian, S AhmadAbstract:This report revises the original report that was published in 1980. Some of the topics covered in the earlier report were provisional and it is now practicable to reexamine them using new or revised geotechnical data and that obtained from SPR cavern operations, which involves 16 new caverns. Revised structure maps and sections show interpretative differences as compared with the 1980 report and more definition in the Dome shape and caprock structural contours, especially a major southeast-northwest trending anomalous zone. The original interpretation was of westward tilt of the Dome, this revision shows a tilt to the southeast, consistent with other gravity and seismic data. This interpretation refines the evaluation of additional cavern space, by adding more Salt buffer and allowing several more caverns. Additional storage space is constrained on this nearly full Dome because of low-lying peripheral wetlands, but 60 MMBBL or more of additional volume could be gained in six or more new caverns. Subsidence values at Bryan Mound are among the lowest in the SPR system, averaging about 11 mm/yr (0.4 in/yr), but measurement and interpretation issues persist, as observed values are about the same as survey measurement accuracy. Periodic flooding is a continuing threat because ofmore » the coastal proximity and because peripheral portions of the site are at elevations less than 15 ft. This threat may increase slightly as future subsidence lowers the surface, but the amount is apt to be small. Caprock integrity may be affected by structural features, especially the faulting associated with anomalous zones. Injection wells have not been used extensively at Bryan Mound, but could be a practicable solution to future brine disposal needs. Environmental issues center on the areas of low elevation that are below 15 feet above mean sea level: the coastal proximity and lowland environment combined with the potential for flooding create conditions that require continuing surveillance.« less
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Strategic Petroleum Reserve (SPR) additional geologic site characterization studies, Bayou Choctaw Salt Dome, Louisiana
1993Co-Authors: J.t. Neal, T.r. Magorian, K.o. Byrne, S. DenzlerAbstract:This report revises and updates the geologic site characterization report that was published in 1980. Revised structure maps and sections show interpretative differences in the Dome shape and caprock structural contours, especially a major east-west trending shear zone, not mapped in the 1980 report. Excessive gas influx in Caverns 18 and 20 may be associated with this shear zone. Subsidence values at Bayou Choctaw are among the lowest in the SPR system, averaging only about 10 mm/yr but measurement and interpretation issues persist, as observed values often approximate measurement accuracy. Periodic, temporary flooding is a continuing concern because of the low site elevation (less than 10 ft), and this may intensify as future subsidence lowers the surface even further. Cavern 4 was re-sonared in 1992 and the profiles suggest that significant change has not occurred since 1980, thereby reducing the uncertainty of possible overburden collapse -- as occurred at Cavern 7 in 1954. Other potential integrity issues persist, such as the proximity of Cavern 20 to the Dome edge, and the narrow web separating Caverns 15 and 17. Injection wells have been used for the disposal of brine but have been only marginally effective thus far; recompletions into more permeable more » lower Pleistocene gravels may be a practical way of increasing injection capacity and brinefield efficiency. Cavern storage space is limited on this already crowded Dome, but 15 MMBBL could be gained by enlarging Cavern 19 and by constructing a new cavern beneath and slightly north of abandoned Cavern 13. Environmental issues center on the low site elevation: the backswamp environment combined with the potential for periodic flooding create conditions that will require continuing surveillance. « less
Byoung Yoon Park - One of the best experts on this subject based on the ideXlab platform.
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geomechanical model calibration using field measurements for a petroleum reserve
Rock Mechanics and Rock Engineering, 2018Co-Authors: Byoung Yoon Park, Steven R. Sobolik, Courtney G HerrickAbstract:A finite element numerical analysis model has been constructed that consists of a mesh that effectively captures the geometries of Bayou Choctaw (BC) Strategic Petroleum Reserve (SPR) site and multimechanism deformation (M-D) Salt constitutive model using the daily data of actual wellhead pressure and oil–brine interface location. The Salt creep rate is not uniform in the Salt Dome, and the creep test data for BC Salt are limited. Therefore, the model calibration is necessary to simulate the geomechanical behavior of the Salt Dome. The cavern volumetric closures of SPR caverns calculated from CAVEMAN are used as the field baseline measurement. The structure factor, A2, and transient strain limit factor, K0, in the M-D constitutive model are used for the calibration. The value of A2, obtained experimentally from BC Salt, and the value of K0, obtained from Waste Isolation Pilot Plant Salt, are used for the baseline values. To adjust the magnitude of A2 and K0, multiplication factors A2F and K0F are defined, respectively. The A2F and K0F values of the Salt Dome and Salt drawdown skins surrounding each SPR cavern have been determined through a number of back analyses. The cavern volumetric closures calculated from this model correspond to the predictions from CAVEMAN for six SPR caverns. Therefore, this model is able to predict behaviors of the Salt Dome, caverns, caprock, and interbed layers. The geotechnical concerns associated with the BC site from this analysis will be explained in a follow-up paper.
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three dimensional simulation for big hill strategic petroleum reserve spr
2005Co-Authors: Brian L. Ehgartner, Byoung Yoon Park, Steven R. Sobolik, M Y LeeAbstract:3-D finite element analyses were performed to evaluate the structural integrity of caverns located at the Strategic Petroleum Reserve's Big Hill site. State-of-art analyses simulated the current site configuration and considered additional caverns. The addition of 5 caverns to account for a full site and a full Dome containing 31 caverns were modeled. Operations including both normal and cavern workover pressures and cavern enlargement due to leaching were modeled to account for as many as 5 future oil drawdowns. Under the modeled conditions, caverns were placed very close to the edge of the Salt Dome. The web of Salt separating the caverns and the web of Salt between the caverns and edge of the Salt Dome were reduced due to leaching. The impacts on cavern stability, underground creep closure, surface subsidence and infrastructure, and well integrity were quantified. The analyses included recently derived damage criterion obtained from testing of Big Hill Salt cores. The results show that from a structural view point, many additional caverns can be safely added to Big Hill.
