Fast dual-domain reduced-rank algorithm for 3D deblending via randomized QR decomposition

We have developed a fast dual-domain algorithm based on matrix rank reduction for separating simultaneous-source seismic data. Our algorithm operates on 3D common receiver gathers or offset-midpoint gathers. At a given monochromatic frequency slice in the [Formula: see text]-[Formula: see text]-[Formula: see text] domain, the spatial data of the ideal unblended common receiver or offset-midpoint gather could be represented via a low-rank matrix. The interferences from the randomly and closely fired shots increased the rank of the aforementioned matrix. Therefore, we could minimize the misfit between the blended observation and the predicted blended data subject to a low-rank constraint that was applied to the data in the [Formula: see text]-[Formula: see text]-[Formula: see text] domain. The low-rank constraint could be implemented via the classic truncated singular value decomposition (SVD) or via a randomized QR decomposition (rQRd). The rQRd yielded nearly one order of processing time improvement with respect to the truncated SVD. We have also discovered that the rQRd was less stringent on the selection of the rank of the data. The latter was important because we often had no precise knowledge of the optimal rank that was required to represent the data. We adopted a synthetic 3D vertical seismic profile and a real seismic data set acquired at the North Viking Graben to test the performance of the proposed source separation algorithm. The proposed algorithm effectively eliminated the interferences while preserving the desired unblended signal. Especially for the synthetic vertical seismic profile example, experiments were evaluated under different survey time ratios. Our tests indicated that the proposed method could save up to 90% of acquisition time under a self-simultaneous source acquisition scenario.

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Integrated prestack depth migration of vertical seismic profile and surface seismic data from the Rocky Mountain Foothills of southern Alberta, Canada

Geophysics ◽

10.1190/1.1635031 ◽

2003 ◽

Vol 68 (6) ◽

pp. 1782-1791 ◽

Cited By ~ 1

Author(s):

M. Graziella Kirtland Grech ◽

Don C. Lawton ◽

Scott Cheadle

Keyword(s):

Seismic Data ◽

Rocky Mountain ◽

Velocity Model ◽

Seismic Profile ◽

Vertical Seismic Profile ◽

Prestack Depth Migration ◽

Data Set ◽

Depth Migration ◽

Southern Alberta ◽

Vsp Data

We have developed an anisotropic prestack depth migration code that can migrate either vertical seismic profile (VSP) or surface seismic data. We use this migration code in a new method for integrated VSP and surface seismic depth imaging. Instead of splicing the VSP image into the section derived from surface seismic data, we use the same migration algorithm and a single velocity model to migrate both data sets to a common output grid. We then scale and sum the two images to yield one integrated depth‐migrated section. After testing this method on synthetic surface seismic and VSP data, we applied it to field data from a 2D surface seismic line and a multioffset VSP from the Rocky Mountain Foothills of southern Alberta, Canada. Our results show that the resulting integrated image exhibits significant improvement over that obtained from (a) the migration of either data set alone or (b) the conventional splicing approach. The integrated image uses the broader frequency bandwidth of the VSP data to provide higher vertical resolution than the migration of the surface seismic data. The integrated image also shows enhanced structural detail, since no part of the surface seismic section is eliminated, and good event continuity through the use of a single migration–velocity model, obtained by an integrated interpretation of borehole and surface seismic data. This enhanced migrated image enabled us to perform a more robust interpretation with good well ties.

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Enhanced low-rank matrix estimation for simultaneous denoising and reconstruction of five-dimensional seismic data

Geophysics ◽

10.1190/geo2020-0773.1 ◽

2021 ◽

pp. 1-96

Author(s):

Yapo Abolé Serge Innocent Oboué ◽

Yangkang Chen

Keyword(s):

Seismic Data ◽

Hankel Matrix ◽

Low Rank ◽

The Novel ◽

Proximity Function ◽

Rank Reduction ◽

Matrix Estimation ◽

Useful Signal ◽

Truncated Svd ◽

Noisy Observation

Noise and missing traces usually influence the quality of multidimensional seismic data. It is, therefore, necessary to e stimate the useful signal from its noisy observation. The damped rank-reduction (DRR) method has emerged as an effective method to reconstruct the useful signal matrix from its noisy observation. However, the higher the noise level and the ratio of missing traces, the weaker the DRR operator becomes. Consequently, the estimated low-rank signal matrix includes a unignorable amount of residual noise that influences the next processing steps. This paper focuses on the problem of estimating a low-rank signal matrix from its noisy observation. To elaborate on the novel algorithm, we formulate an improved proximity function by mixing the moving-average filter and the arctangent penalty function. We first apply the proximity function to the level-4 block Hankel matrix before the singular value decomposition (SVD), and then, to singular values, during the damped truncated SVD process. The relationship between the novel proximity function and the DRR framework leads to an optimization problem, which results in better recovery performance. The proposed algorithm aims at producing an enhanced rank-reduction operator to estimate the useful signal matrix with a higher quality. Experiments are conducted on synthetic and real 5-D seismic data to compare the effectiveness of our approach to the DRR approach. The proposed approach is shown to obtain better performance since the estimated low-rank signal matrix is cleaner and contains less amount of artifacts compared to the DRR algorithm.

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Imaging below a complex overburden with borehole-seismic data

Geophysics ◽

10.1190/geo2019-0123.1 ◽

2020 ◽

Vol 85 (3) ◽

pp. S135-S150

Author(s):

Jakob B. U. Haldorsen ◽

Leif Jahren

Keyword(s):

Economic Evaluation ◽

Seismic Data ◽

Seismic Profile ◽

Profile Data ◽

Vertical Seismic Profile ◽

S Waves ◽

Critical Information ◽

Measured Polarization ◽

Borehole Seismic

We have determined how the measured polarization and traveltime for P- and S-waves can be used directly with vertical seismic profile data for estimating the salt exit points in a salt-proximity survey. As with interferometry, the processes described use only local velocities. For the data analyzed in this paper, our procedures have confirmed the location, inferred from surface-seismic data, of the flank of a steeply dipping salt body near the well. This has provided us more confidence in the estimated reservoir extent moving toward the salt face, which in turn has added critical information for the economic evaluation of a possible new well into the reservoir. We also have found that ray-based vector migration, based on the assumptions of locally plane wavefronts and locally plane formation interfaces, can be used to create 3D reflection images of steeply dipping sediments near the well, again using only local velocities. Our local reflection images have helped confirm the dips of the sediments between the well and the salt flank. Because all parameters used in these processes are local and can be extracted from the data themselves, the processes can be considered to be self-sufficient.

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A procedure for optimally removing localized coherent noise

Geophysics ◽

10.1190/1.1443746 ◽

1995 ◽

Vol 60 (1) ◽

pp. 191-203 ◽

Cited By ~ 23

Author(s):

A. Frank Linville ◽

Robert A. Meek

Keyword(s):

Seismic Data ◽

Seismic Profile ◽

Noise Attenuation ◽

Signal Distortion ◽

Coherent Noise ◽

Vertical Seismic Profile ◽

Seismic Records ◽

Signal Distortions ◽

Notch Filtering ◽

Phase Differences

Primary reflections in seismic records are often obscured by coherent noise making processing and interpretation difficult. Trapped water modes, surface waves, scattered waves, air waves, and tube waves to name a few, must be removed early in the processing sequence to optimize subsequent processing and imaging. We have developed a noise canceling algorithm that effectively removes many of the commonly encountered noise trains in seismic data. All currently available techniques for coherent noise attenuation suffer from limitations that introduce unacceptable signal distortions and artifacts. Also, most of those techniques impose the dual stringent requirements of equal and fine spatial sampling in the field acquisition of seismic data. Our technique takes advantage of characteristics usually found in coherent noise such as being localized in time, highly aliased, nondispersive (or only mildly so), and exhibit a variety of moveout patterns across the seismic records. When coherent noise is localized in time, a window much like a surgical mute is drawn around the noise. The algorithm derives an estimate of the noise in the window, automatically correcting for amplitude and phase differences, and adaptively subtracts this noise from the window of data. This signal estimate is then placed back in the record. In a model and a land data example, the algorithm removes noise more effectively with less signal distortion than does f-k filtering or velocity notch filtering. Downgoing energy in a vertical seismic profile (VSP) with irregular receiver spacing is also removed.

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PRACTICAL USE OF BOREHOLE SEISMIC IN EXPLORATION

The APPEA Journal ◽

10.1071/aj83034 ◽

1984 ◽

Vol 24 (1) ◽

pp. 429

Author(s):

F. Sandnes W. L. Nutt ◽

S. G. Henry

Keyword(s):

Seismic Data ◽

Seismic Profile ◽

Seismic Survey ◽

Vertical Seismic Profile ◽

Direct Signal ◽

Seismic Fault ◽

Time Calibration ◽

Vsp Data ◽

Borehole Seismic ◽

Processing Techniques

The improvement of acquisition and processing techniques has made it possible to study seismic wavetrains in boreholes.With careful acquisition procedures and quantitative data processing, one can extract useful information on the propagation of seismic events through the earth, on generation of multiples and on the different reflections coming from horizons that may not all be accessible by surface seismic.An extensive borehole seismic survey was conducted in a well in Conoco's contract area 'Block B' in the South China Sea. Shots at 96 levels were recorded, and the resulting Vertical Seismic Profile (VSP) was carefully processed and analyzed together with the Synthetic Seismogram (Geogram*) and the Synthetic Vertical Seismic Profile (Synthetic VSP).In addition to the general interpretation of the VSP data, i.e. time calibration of surface seismic, fault identification, VSP trace inversion and VSP Direct Signal Analysis, the practical inclusion of VSP data in the reprocessing of surface seismic data was studied. Conclusions that can be drawn are that deconvolution of surface seismic data using VSP data must be carefully approached and that VSP can be successfully used to examine phase relationships in seismic data.

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Antialiasing condition and filter for the reciprocity equation of correlation type

Geophysics ◽

10.1190/1.3495542 ◽

2010 ◽

Vol 75 (6) ◽

pp. WB219-WB224 ◽

Cited By ~ 1

Author(s):

Weiping Cao ◽

Gerard T. Schuster

Keyword(s):

Seismic Data ◽

Seismic Profile ◽

Numerical Results ◽

Numerical Implementation ◽

Vertical Seismic Profile ◽

Vsp Data ◽

And Migration

An antialiasing formula has been derived for interferometric redatuming of seismic data. More generally, this formula is valid for numerical implementation of the reciprocity equation of correlation type, which is used for redatuming, extrapolation, interpolation, and migration. The antialiasing condition can be, surprisingly, more tolerant of a coarser trace sampling compared to the standard antialiasing condition. Numerical results with synthetic vertical seismic profile (VSP) data show that interferometry artifacts are effectively reduced when the antialiasing condition is used as a constraint with interferometric redatuming.

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Reflectivity randomness revisited

Geophysics ◽

10.1190/1.1444668 ◽

1999 ◽

Vol 64 (5) ◽

pp. 1630-1636 ◽

Cited By ~ 1

Author(s):

Ayon K. Dey ◽

Larry R. Lines

Keyword(s):

Seismic Data ◽

Real Data ◽

Seismic Profile ◽

Synthetic Seismograms ◽

Seismic Exploration ◽

Well Log ◽

Simple Test ◽

Vertical Seismic Profile ◽

Seismic Reflectivity

In seismic exploration, statistical wavelet estimation and deconvolution are standard tools. Both of these processes assume randomness in the seismic reflectivity sequence. The validity of this assumption is examined by using well‐log synthetic seismograms and by using a procedure for evaluating the resulting deconvolutions. With real data, we compare our wavelet estimations with the in‐situ recording of the wavelet from a vertical seismic profile (VSP). As a result of our examination of the randomness assumption, we present a fairly simple test that can be used to evaluate the validity of a randomness assumption. From our test of seismic data in Alberta, we conclude that the assumption of reflectivity randomness is less of a problem in deconvolution than other assumptions such as phase and stationarity.

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A rapid seismic data calibration technique using integrated micro-electro-mechanical system inertial sensor groups for a 3C vertical seismic profile

Geophysics ◽

10.1190/geo2016-0218.1 ◽

2017 ◽

Vol 82 (6) ◽

pp. P109-P118

Author(s):

Huailiang Li ◽

Xianguo Tuo ◽

Tong Shen ◽

Mark Julian Henderson ◽

Jérémie Courtois

Keyword(s):

Mechanical System ◽

Seismic Data ◽

Inertial Sensors ◽

Inertial Sensor ◽

Low Cost ◽

Measuring Method ◽

Seismic Profile ◽

Micro Electro Mechanical System ◽

Vertical Seismic Profile ◽

Sensor Package

Calibration of 3C vertical seismic profile (VSP) data is an exciting challenge because the orientation of the tool is random when only seismic data are considered. We have augmented the sensor package on the VSP tool with micro-electro-mechanical system (MEMS) inertial sensors and applied a gesture measuring method to determine the tool orientation and calibration. This technique can quickly produce high precision, orientation, and angle information when integrated with the seismometer. The augmented sensor package consists of a low-cost triaxial MEMS gyroscope, an electronic compass, and an accelerometer. The technique to process the gesture information is based on the OpenGL software for 3D modeling. We have tested this approach on a large number of field data sets and it appeared to be faster and more reliable than other approaches.

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Subsalt Depth Imaging Using 3-D VSP Technique in the Ras El Ush Field, Gulf of Suez, Egypt

GeoArabia ◽

10.2113/geoarabia0403363 ◽

1999 ◽

Vol 4 (3) ◽

pp. 363-378

Author(s):

Mohammed A. Badri ◽

Taha M. Taha ◽

Robert W. Wiley

Keyword(s):

Seismic Data ◽

Seismic Profile ◽

Poor Quality ◽

Gulf Of Suez ◽

Geological Model ◽

Vertical Seismic Profile ◽

Depth Imaging ◽

Vsp Data ◽

Basement High ◽

Definition Of

ABSTRACT In 1995 oil was discovered in the pre-Miocene Matulla and Nubia Sandstones in the Ras El Ush field, Gulf of Suez, Egypt. The discovery was based on an aeromagnetic anomaly from a basement high. After drilling several delineation wells, based on a geological model, it became evident that the field is very complex as it is broken into tilted and rotated compartmental blocks by two perpendicular fault systems. Also the 2-D seismic data were of poor quality beneath the thick Miocene South Gharib Evaporite. Since part of the field lies below shallow-water, 3-D seismic was considered to be too costly. When a delineation well did not encounter the reservoir, due to an unanticipated fault, a 2-D walkaway Vertical Seismic Profile (VSP) was acquired. It clearly revealed the presence of a cross fault. The success of the 2-D VSP in imaging the fault led to the acquisition of the first Middle East 3-D VSP survey in the following well. A downhole, tri-axial, five geophone array tool was used to acquire the 3-D VSP. The 3-D volume of the final migrated VSP data provided the means for the reliable mapping of horizons beneath the South Gharib Evaporite. These maps improved the definition of the field and helped detect previously unrecognized prospective blocks. Four further successful delineation wells confirmed the 3-D VSP interpretation.

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An integrated surface seismic/seismic profile case study: Simonette area, Alberta

Geophysics ◽

10.1190/1.1443383 ◽

1993 ◽

Vol 58 (11) ◽

pp. 1676-1688

Author(s):

Ronald C. Hinds ◽

Neil L. Anderson ◽

Richard Kuzmiski

Keyword(s):

Seismic Data ◽

Cost Effective ◽

Seismic Profile ◽

Viable Alternative ◽

Target Area ◽

Vertical Seismic Profile ◽

Subsurface Geology ◽

Well Location ◽

Vsp Data

On the basis of conventional surface seismic data, the 13–15–63–25W5M exploratory well was drilled into a low‐relief Leduc Formation reef (Devonian Woodbend Group) in the Simonette area, west‐central Alberta, Canada. The well was expected to intersect the crest of the reef and encounter about 50–60 m of pay; unfortunately it was drilled into a flank position and abandoned. The decision to abandon the well, as opposed to whipstocking in the direction of the reef crest, was made after the acquisition and interpretive processing of both near( and far‐offset (252 and 524 m, respectively) vertical seismic profile (VSP) data, and after the reanalysis of existing surface seismic data. The near‐ and far‐offset VSPs were run and interpreted while the drill rig remained on‐site, with the immediate objectives of: (1) determining an accurate tie between the surface seismic data and the subsurface geology; and (2) mapping relief along the top of the reef over a distance of 150 m from the 13–15 well location in the direction of the adjacent productive 16–16 well (with a view to whipstocking). These surveys proved to be cost‐effective in that the operators were able to determine that the crest of the reef was out of the target area, and that whipstocking was not a viable alternative. The use of VSP surveys in this situation allowed the operators to avoid the costs associated with whipstocking, and to feel confident with their decision to abandon the well.

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