188bet vietnam Merging of 3D seismic data
Summary
Merging of individual seismic datasets into a single uniform dataset is useful for structure analysis, geological modelling, and seismic attribute analysis for a large area. However, many challenges are met, both from 188bet vietnam acquisition aspect to processing of data before merging. 188bet vietnam authors investigate in detail 188bet vietnam technical difficulties of merging data, and discuss methods to accomplish 188bet vietnam goal with an emphasis on post stack seismic merging, as well as merging results from our processing of field seismic datasets.
Key words: Merging seismic data, seismic data processing, special seismic techniques.
1. Introduction
Seismic survey data has 188bet vietnam pioneering role in laterally extending 188bet vietnam geological study area. A regional-scale seismic study, such as 188bet vietnam study of a basin, may face a stiff challenge where 188bet vietnam area is so vast that it might not be coverable by a single seismic survey. In order to do so, 188bet vietnam ability to combine and blend information from individual surveys becomes necessary.
Nowadays, a number of 3D seismic surveys has been carried out each year on 188bet vietnam continental shelf of Vietnam with a typical coverage area ranging from about 100km2 to 3,500km2, usually within a study block. 188bet vietnam division of 188bet vietnam continental shelf into blocks and assignment to different operation companies also implies that each 3D seismic survey is limited to 188bet vietnam block operated by a company. A regional-scale geological assessment, therefore, will be very difficult since 188bet vietnam data is a collection of patchy seismic surveys that often have different acquisition characteristics and thus distinctive recorded seismic data characteristics.
Certainly, reacquiring seismic data for 188bet vietnam whole region and processing 188bet vietnam data as a large single seismic dataset may solve part of 188bet vietnam problem of patchy data. However, this is unrealistic and prohibitive due to expensive costs and long computation time, not to mention 188bet vietnam regional administrative problems as well as difficulties with 188bet vietnam survey design phase to comprehensively cover various local structures’ orientation. A more feasible alternative is to merge available “small” overlapping 3D vintage seismic data into a single dataset with uniform amplitude, frequency, and phase. A merged seismic dataset should provide a reasonable approximation to full area acquired/processed data at a much economical cost and shorter operation/processing time.
In fact, seismic data merging has been performed regularly on many foreign projects [1 - 3] and 188bet vietnam results have been very encouraging. Figure 1 shows an example map of several overlapping surveys in India [1] subjected to 188bet vietnam merging process.
There are several important applications of merged seismic data. 188bet vietnam subsurface image of regions near 188bet vietnam edges of a local survey is usually distorted from 188bet vietnam migration due to 188bet vietnam deficiency of input seismic data, which eventually can be compensated by another overlapped survey data [1]. 188bet vietnam most important application is probably 188bet vietnam ability to carry out 188bet vietnam interpretation of structures continuously and seamlessly on 188bet vietnam merged seismic data from one local region to another, and hence enable many geological analyses for a large area such as 188bet vietnam structural analysis, sequence stratigraphy analysis, etc. Moreover, many attribute extraction applications can also be performed on 188bet vietnam merged dataset such as various seismic attribute analyses, PaleoScan software, etc.
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2. Technical difficulties with merging seismic data
188bet vietnam process of merging seismic data is basically related to 188bet vietnam compensation for 188bet vietnam differences in seismic characteristics of various overlapping datasets. 188bet vietnam variation in seismic characteristics between datasets can broadly be categorised as coming from 2 major sources: 188bet vietnam widely varying seismic acquisition configurations and 188bet vietnam differences in processing technologies. We will discuss 188bet vietnam effect of each type of variations on 188bet vietnam seismic characteristics as follow.
Effect of variations in acquisition schemes
Each seismic survey is usually designed with a specific goal suitable for a particular local region. Thus, different seismic surveys in nearby regions may have different acquisition parameters. We concentrate on a few important acquisition parameters.
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Figure 2. Drastic amplitude differences between two overlapping surveys
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Figure 3. 188bet vietnam impact of 188bet vietnam ghost notching frequency on 188bet vietnam frequency content of 188bet vietnam acquired signal [4]
188bet vietnam most obvious differences are due to 188bet vietnam acquisition configuration on 188bet vietnam survey boat such as 188bet vietnam source configuration, including 188bet vietnam types of 188bet vietnam source - air gun, vibroseis, dynamite, 188bet vietnam geometry of 188bet vietnam source array, and 188bet vietnam volumes of individual guns, etc. In addition, 188bet vietnam variation in 188bet vietnam configuration of 188bet vietnam receiver side may include 188bet vietnam number and length of 188bet vietnam streamer cables, 188bet vietnam interval of 188bet vietnam receivers, 188bet vietnam type of receivers such as hydrophones, velocity phones, 188bet vietnam recording and sampling intervals, 188bet vietnam frequency of anti-aliasing filter, etc. Those differences provide decisive impacts on 188bet vietnam amplitude and frequency content of 188bet vietnam acquired seismic data, 188bet vietnam signal to noise ratio (SNR), as well as 188bet vietnam fold density at local common middle points. Drastic amplitude differences between two overlapping surveys can be seen in Figure 2.
188bet vietnam frequency content differences may come from another source. Nearby surveys may have different source depths and receiver depths that can affect 188bet vietnam ghost frequencies. Typically, 188bet vietnam ghost notch frequency is related to 188bet vietnam source or receiver depth by 188bet vietnam formula [4]
Where Vwater is 188bet vietnam seismic velocity in 188bet vietnam water medium, d is 188bet vietnam depth of 188bet vietnam source or receiver and fnotch is 188bet vietnam notching frequency. 188bet vietnam effect of 188bet vietnam ghost notch on 188bet vietnam frequency content is illustrated in Figure 3.
188bet vietnam frequency limitation by 188bet vietnam ghost notches, in turn, will affect 188bet vietnam signal frequency bandwidth, which will impact 188bet vietnam seismic resolution as well as 188bet vietnam wavelet shape. Seismic frequency content and resolution differences, as a combination of several factors, can be seen in Figure 4 where 188bet vietnam survey on 188bet vietnam left has a much lower frequency content and resolution, comparing with 188bet vietnam survey on 188bet vietnam right.
New acquisition advancements such as PGS’s GeoStreamer/GeoSource [5, 6] or CGG-Veritas’ BroadSeis [7] technologies will further widen 188bet vietnam seismic frequency bandwidth/resolution differences comparing to 188bet vietnam seismic data acquired from 188bet vietnam traditional hydrophone - flat cable configuration.
188bet vietnam presence of external factors such as acquisition time (tidal change), changing weather (rough vs quiet sea for marine acquisition), changing unconsolidated layer thickness (for land acquisition) might result in another class of problems which is 188bet vietnam differences in phases and statics between overlapping surveys. 188bet vietnam phase/static differences are troublesome for interpretation horizons to align from a seismic dataset to another. 188bet vietnam effect and correction for phase/static problem is discussed further in Section 3.
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Figure 4. 188bet vietnam difference of 188bet vietnam signal frequency bandwidth/resolution
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Figure 5. Location map showing 188bet vietnam Grid orientation and Master grid
A parameter that is also frequently changing from survey to survey is 188bet vietnam acquisition azimuth/ orientation. This leads to 188bet vietnam differences to 188bet vietnam orientation of 188bet vietnam migration grid (inline-crossline grid) in 188bet vietnam post-acquisition seismic processing workflow. A typical 3 survey overlapping grid configuration is shown in Figure 5. As we can see, each grid system has a different inline orientation, as well as different grid binning dimensions, not to mention 188bet vietnam possible CMP- fold differences.
188bet vietnam discrepancy in 188bet vietnam grid orientations eventually leads to 188bet vietnam need to re-grid seismic datasets in to a common encompassing grid system (master grid) and re-number 188bet vietnam inline and crossline during 188bet vietnam seismic merging process (Section 3).
A less obvious effect of 188bet vietnam differences in 188bet vietnam sail-line’s direction is related to 188bet vietnam amount of seismic illumination. For a single survey orientation, underground geological objects may have certain seismic features being illuminated better than other depending on 188bet vietnam alignment of 188bet vietnam object and 188bet vietnam sail-line’s direction. This can be illustrated in Figure 6 where, as part of 188bet vietnam survey design process at 188bet vietnam VPI, we simulate 188bet vietnam seismic illumination of a target horizon/ fault under different sail-line azimuths of 188bet vietnam survey boat with other acquisition parameters kept 188bet vietnam same. As we can see a major fault is illuminated differently under different sail-line orientation. 188bet vietnam differences in 188bet vietnam amount of seismic illuminations on 188bet vietnam same geological object mean that 188bet vietnam images of 188bet vietnam same object on 188bet vietnam final overlapping seismic cube may have different apparent, amplitude and image quality, which requires 188bet vietnam amplitude conditioning before merging.
(a) (b) (c)
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Figure 6. Different seismic illumination on 188bet vietnam same fault depending on 188bet vietnam sail line azimuth: a. 168 degree, b. 258 degree, and c. 319 degree. Illumination by 188bet vietnam 258 degree sail lineazimuth appears to create 188bet vietnam clearest observation of 188bet vietnam fault surface.
Differences in seismic data processing routines
188bet vietnam differences in processing workflows from various contractors should also present some problems with merging seismic surveys. Each processing jobs may have dramatically different objectives, and technologies including:
- Different target objects that may lie at different depth (shallow vs. deep).
- Different technologies used in 188bet vietnam process, such as PSTM, PSDM, and CBM, etc.
- Different parameters used in 188bet vietnam flows (possibly on 188bet vietnam same dataset).
We highlight some major aspects, including phase/static, amplitudes, frequencies, and SNR, that 188bet vietnam differences impact 188bet vietnam merging process.
A common issue is related to 188bet vietnam misalignment of events between two overlapping datasets, also known as 188bet vietnam static/phase problem. Beside those originated from 188bet vietnam survey configuration differences, 188bet vietnam causes of 188bet vietnam misalignment might also be traced to several processing routines:
- 188bet vietnam difference in velocities used in 188bet vietnam seismic migration might lead to some events (dipping reflection planes) to be migrated to a different time/depth comparing to one processed from 188bet vietnam other routine.
- 188bet vietnam misalignment may also come from 188bet vietnam differences between 188bet vietnam time and depth migration, and 188bet vietnam dipping features may not align for 188bet vietnam PSTM and PSDM converted to time.
- Another source of misalignments is from 188bet vietnam different level of Q-compensation between datasets - leading to different phase shifts.
- Events at 188bet vietnam edges of a survey is usually observed to have incorrect imaging time/depth due to 188bet vietnam insufficient input seismic points for 188bet vietnam migration.
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Figure 7. Seismic event misalignments of two seismic survey
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Figure 8. Technology differences comparison - FX Migration vs PSTM Migration
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Figure 9. Technology differences comparison - PSDM vs CBM
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Figure 10. Combination of 188bet vietnam differences in seismic acquisition and processing may result in two overlapping seismic sections (left and right) with completely different appearances
Seismic event misalignments are serious because in case you are willing to align those events at a certain depth, events at other depths may still misalign.
Another discrepancy is about 188bet vietnam amplitude between overlapping seismic data. Beside 188bet vietnam cause from 188bet vietnam acquisition configuration factors (as discussed above), 188bet vietnam variation in 188bet vietnam seismic amplitude might be 188bet vietnam consequence of 188bet vietnam difference in migration apertures (each image point receives contributions from a varying number of traces). 188bet vietnam processing flow may further contribute to it by various amplitude compensation such as 188bet vietnam post stack time-variant scaling, Automatic Gain Control. Amplitude compensation for 188bet vietnam absorption (Q-compensation) might be different in workflows from different processing contractors.
Thedifferences in 188bet vietnam amount of Q-compensation might also be 188bet vietnam source of differences in 188bet vietnam frequency content of two overlapping surveys. Besides, frequency manipulation techniques such as spectral shaping, spectral whitening, spectral bluing, source deconvolution, and source wavelet de-ghosting, etc. might affect 188bet vietnam frequency content between two datasets. However, for 188bet vietnam marine data, these drastic frequency-altering techniques are not usually offered by 188bet vietnam processing contractor to preserve 188bet vietnam original frequency bandwidth (unless requested by 188bet vietnam client).
An often-overlooked aspect is 188bet vietnam merging of datasets with different SNR, which might make 188bet vietnam final results look synthetic (a poor dataset is stitched to a good dataset). Newer computing hardware resources enable more advanced processing/ imaging algorithms that can provide seismic results with enhanced SNR and new seismic features shown up comparing to 188bet vietnam vintage. 188bet vietnam example shown in Figure 8 is 188bet vietnam comparison of 188bet vietnam seismic quality from results processed by 188bet vietnam old FX migration in 2001 (left) and reprocessed by 188bet vietnam PSTM algorithm in 2002, in which, 188bet vietnam quality of PSTM seismic data is significantly improved, in terms of details (resolution) and frequency bandwidth, compared to 188bet vietnam old (possibly obsoleted) FX migration seismic data.
Figure 9 illustrates another comparison between 188bet vietnam old PSDM and 188bet vietnam newer CBM processing, where many features, such as faults, top basement show up more clearly on 188bet vietnam final CBM stack section, comparing to 188bet vietnam vintage PSDM processing. Overlapping seismic datasets with different level of SNR will cause difficulties in matching up data, or lining-up events. A possible remedy is to perform seismic enhancement for poor quality data such as one described in a recent study from our group [8], although 188bet vietnam results might be limited after stacking has been performed. Or better, input seismic data might be inspected before merging to select those with similar SNR.
188bet vietnam accumulation effect of various types of differences from 188bet vietnam survey configuration to seismic signal processing may result in seismic sections of 188bet vietnam overlapping region with significant different appearances such as one in Figure 10. In this case, a decision will need to be made regarding 188bet vietnam merge border, which, in turn, will decide which part of 188bet vietnam individual survey will remain in 188bet vietnam merged dataset, and which part will be thrown away.
3. Merging 3D post-stack data
188bet vietnam goal of 188bet vietnam merging of 3D post-stack seismic surveys is to create a single 3D seismic cube which balances 188bet vietnam phase and amplitude of individual stacked input seismic cubes. For geological structure and seismic attribute analysis, 188bet vietnam results might be adequate, but certainly cannot be as good as merging pre-migration seismic data. 188bet vietnam workflow can be summarised in 5 major processing steps as shown in Figure 11. Note that 188bet vietnam flow chart is over-simplified and each major step can be rerun as needed.
Regrid of seismic data
As discussed in Section 2, due to 188bet vietnam differences in survey orientations, overlapping surveys may have different migration grids with different azimuths and different CDP spacings. Re-gridding of seismic data is essentially spatial resampling (i.e. interpolation) of data by points on a common encompassing master grid (Figure 5). In our experiences, 188bet vietnam selection of 188bet vietnam master grid may fall into one of 188bet vietnam two popular choices:
- We can select 188bet vietnam orientation of 188bet vietnam majority of 188bet vietnam surveys, which has 188bet vietnam benefit of having a smaller number of surveys to be regridded.
- Or we can select 188bet vietnam orientation of 188bet vietnam master grid to be orthogonal to 188bet vietnam major fault or features of concern.
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Figure 11. Five major steps flowchart in merging post-stack seismic data
Various interpolation schemes exist such as bilinear interpolation, bicubic interpolation, polynomial interpolation or spline interpolation, etc. We chose 188bet vietnam sinc function interpolation (Whittaker- Shannon interpolation) since it is 188bet vietnam perfect reconstruction of 188bet vietnam original (continuous) signal according to 188bet vietnam Shannon sampling theorem [9]. In one dimension, 188bet vietnam interpolation takes 188bet vietnam form of:
Where t is 188bet vietnam continuous time/ space variable, sinc(t) = sin(πt)/(πt) and T is usually 188bet vietnam sampling rate that gives 188bet vietnam samples {x[n]}. From 188bet vietnam interpolation formula, resampling simply means to choose to resample t at a different discrete rate: t = T1, 2T1,…, nT1,… In our case of spatial resampling, we use 188bet vietnam extended 2D version of 188bet vietnam formula. An illustration of re-gridding can be seen in Figure 12 where spatial data points that misalign with 188bet vietnam master grid are resampled into points on 188bet vietnam master grid (located at 188bet vietnam centre of each new cell).
Amplitude conditioning
Amplitude equalisation between overlapping seismic dataset usually means correcting 188bet vietnam amplitude envelopes of one dataset to match with that of 188bet vietnam other one. Since there could be different gain functions applied to 188bet vietnam datasets, 188bet vietnam amplitude correction is usually time-variant too. Figure 13 illustrates 188bet vietnam results from amplitude conditioning where 188bet vietnam amplitude of 188bet vietnam left section is matched to 188bet vietnam one on 188bet vietnam right section. Care has been taken to preserve relative amplitude so that seismic anomalies (such as Direct Hydro Carbon Indicator (DHI)) still show up correctly after amplitude conditioning, as 188bet vietnam amplitude conditioning step only applies a constant smooth gain function (for 188bet vietnam most part of 188bet vietnam merging seismic cubes). As illustrated in Figure 14, a bright spot remains relatively standing out after amplitude conditioning.
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Figure 12. Basemaps grid point before and after re-gridding
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Figure 13. Two merging seismic sections before and after amplitude conditioning
(a) (b)
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Figure 14. A stack section with a bright spot before (a) and after (b) amplitude conditioning. Notice 188bet vietnam range of amplitude of 188bet vietnam original seismic is about -4e5 to 4e5, while 188bet vietnam range of amplitude of 188bet vietnam merging seismic is about -4 to 4. 188bet vietnam bright spot has a relatively high amplitude in both cases.
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Figure 15. Average amplitude spectra from different campaigns [10]
Frequency conditioning
Some special regions may require frequency conditioning due to 188bet vietnam obvious differences in 188bet vietnam frequency spectra. Thus, 188bet vietnam frequency conditioning step aims to minimise 188bet vietnam difference in amplitude spectra (rather than 188bet vietnam energy in 188bet vietnam different section). This is usually accomplished by a matching or shaping filter.
188bet vietnam process of frequency matching may contain an inherent conflict goal. On 188bet vietnam one hand, we want uniform frequency bandwidth on 188bet vietnam merged cube for 188bet vietnam attribute analysis on 188bet vietnam final result and 188bet vietnam easiest way is to choose 188bet vietnam seismic cube with 188bet vietnam lowest frequency bandwidth as 188bet vietnam reference and band-limit 188bet vietnam frequency of other higher-quality cubes. Certainly, this approach will degrade 188bet vietnam quality of some input seismic. On 188bet vietnam other hand, we also desire to preserve as much frequency bandwidth/time resolution as possible, this implies to use 188bet vietnam seismic cube with wider bandwidth as 188bet vietnam reference and to perform shaping filter to enhance 188bet vietnam frequency content of 188bet vietnam seismic data with lower bandwidth (whitening 188bet vietnam data). However, 188bet vietnam result might be limited as whitening 188bet vietnam data too much will amplify 188bet vietnam noise. In drastic cases, a decision on a compromise frequency bandwidth might be made.
An example of performing frequency conditioning can be seen in Figure 15 [10] where 188bet vietnam authors apply spectral whitening to smooth out frequency spectra across 188bet vietnam datasets.
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Figure 16. Two merging seismic sections before and after static conditioning
188bet vietnam differences in 188bet vietnam amount of Q-compensation might be another aspect that is crucial to 188bet vietnam discrepancy in 188bet vietnam frequency content on 188bet vietnam deeper section. Thus, techniques such as to apply inverse Q-compensation and reapply an equal amount of Q can also be carried out if information from 188bet vietnam processing report is available.
Static/phase conditioning
This step is to match 188bet vietnam timing and phase of reflection events on 188bet vietnam overlapping region. Static/phase conditioning is crucial to merging and responsible for 188bet vietnam smooth/seamless look of 188bet vietnam merged cube. In 188bet vietnam actual processing, 188bet vietnam first thing to consider is to make sure all seismic dataset has 188bet vietnam same polarity. This is usually obvious by inspecting major events. Optionally, performing Q-conditioning on 188bet vietnam phase, again, might also be helpful to improve alignments of events on 188bet vietnam deeper sections.
Static/phase conditioning, then, try to align events by 188bet vietnam sub-sample levels. Techniques to estimate 188bet vietnam amount of misalignment may include 188bet vietnam time correlation or 188bet vietnam phase spectra matching. This conditioning step then adjusts 188bet vietnam data by static shifts and phase rotation. In our experiences, events at 188bet vietnam outermost edges might not be easily matched due to 188bet vietnam migration distortion, but they are usually discarded anyway in 188bet vietnam next step.
Figure 16 shows 188bet vietnam effect of matching 188bet vietnam statics from two different datasets. As we can see, major events can be matched and, hence, run continuously between 188bet vietnam two surveys. However, 188bet vietnam result is not perfect as some small residual artifacts of 188bet vietnam borders remain. This is 188bet vietnam basic limitation of performing merging on 188bet vietnam post-stack dataset as static/phase conditioning may not be able to match all events from 188bet vietnam shallow to 188bet vietnam deeper intervals.
Stitching final results
188bet vietnam last step is to merge conditioned seismic cube together. This involves border design and throwing away redundant seismic data (as shown in Figure 10). 188bet vietnam usual added benefit is that discarded seismic is usually 188bet vietnam data at 188bet vietnam edges of 188bet vietnam surveys where major distortions occur.
4. Field data results
We present field data results from 188bet vietnam merging process performed at EPC-VPI. Some more merging results are shown in Figure 17 where we had a seismic section before and after 188bet vietnam merging process. As we can see, events are continuous and 188bet vietnam whole merged section has a uniform amplitude, giving 188bet vietnam perception of a dataset from a single seismic acquisition. 188bet vietnam continuity of 188bet vietnam events can be further illustrated in Figure 18 where we took a time slice before and after 188bet vietnam merging. In this case, after merging, 188bet vietnam border disappears and events are continuous from one side of 188bet vietnam border to 188bet vietnam other side.
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Figure 17. Two merging seismic sections before and after merging process
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Figure 18. Time slice of two merging seismic sections before and after merging process
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Figure 19. RMS analysis on 188bet vietnam merged seismic cube
We also attempted to run an RMS seismic attribute extraction from 188bet vietnam merged seismic cube on a horizon within 188bet vietnam Oligocene layer and 188bet vietnam result is successful (Figure 19). 188bet vietnam attribute map looks continuous throughout 188bet vietnam merge borders, allowing an interpretation of features and abnormal amplitudes, although some minor artifacts from a very small overlapping area (low fold edge region) may remain.
5. Towards 3D premigration pre-stack seismic data merging
As we have seen in Sections 3 and 4, 188bet vietnam problem of misalignments of seismic events can be partially solved by matching phase/static from post-stack seismic cubes (Section 3.2). However, residual artifacts are frequently observed, especially on 188bet vietnam dipping events. This problem can only be solved completely by performing a merge on 188bet vietnam premigration pre-stack seismic data (merging before imaging) such as 188bet vietnam studies in [10 - 13].
Technically, reprocessing and merging from raw data should provide a better result due to 188bet vietnam combination of a common processing/conditioning routine, a common velocity analysis, a common migration grid, and a common migration algorithm. 188bet vietnam advantages of 188bet vietnam premigration- prestack merge results comparing to 188bet vietnam post-stack merge results can be shown in Figure 20 [13] where results from 188bet vietnam premigration-prestack seismic merging show significantly more details in 188bet vietnam overlapping region due to 188bet vietnam added complementary data for migration. Another illustration is shown in Figure 21 [14] from Sino Geophysical with similar observations.
Many issues that have been discussed in Section 2 may remain with premigration-prestack data merging such as 188bet vietnam discrepancies in 188bet vietnam shot records such as shot length, shot density, or receiver intervals, cable length which can be solved by 188bet vietnam shot record regularisation. Another discrepancy might be related to 188bet vietnam CDP folds (midpoint density) and require a CDP fold regularisation also. Usually, trace regularisations (such as 188bet vietnam shot record or cdp fold regularisation) can be accomplished by 188bet vietnam combination of 188bet vietnam trace decimation and 5D trace interpolation.
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| Old post stack merging section New prestack merging section by WEFOX |
Figure 20. A comparison of post-stack and pre-stack merging [12]
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Figure 21. A comparison of post-stack and pre-stack merging [14]
Pre-stack merging of seismic data will be very useful for pre-stack analyses such as AVO and inversion analyses, although at 188bet vietnam cost of some serious technical difficulties. Common sense indicates that 188bet vietnam process of merging premigration data requires huge processing resource requirements (machines and workforces), a long processing time, and a high cost. Various issues like seismic illumination and frequency bandwidth might still be present.
6. Conclusions
3D merging of seismic surveys recorded in different acquisition processes with various acquisition geometries, orientation and processing workflows is a very intricate process. Major problems are 188bet vietnam mismatch of amplitude, frequency bandwidth, static/phases and SNR between overlapping seismic dataset. Fundamentally resolving each problem is necessary to achieve 188bet vietnam goal of treatment and help 188bet vietnam interpreters to meet 188bet vietnam geological objectives. Our hunt for 188bet vietnam solutions has resulted in an in-house merging workflow for 188bet vietnam post-stack data that is relatively fast to execute and cheap to implement on 188bet vietnam available computing hardware. Results processed at 188bet vietnam Vietnam Petroleum Institute (VPI) show a sufficiently good merged dataset that meets 188bet vietnam requirements of uniform amplitudes/frequencies/phases, with a seamless look of 188bet vietnam sections/time slices, and reflection events running continuously from one area to another. Our resultant merged datasets thus look quite promising that they could be used for seamless geological interpretation or continuous seismic attribute analysis. 188bet vietnam limitations of 188bet vietnam post-stack merging process including some dipping events might not be to align very well, some artifacts may remain due to small overlapping area (low fold at 188bet vietnam edge/ migration distortion), and sometimes high-quality data may need to be downgraded to match low-quality data. Those imperfections, although looking minor, sometimes may have serious consequences in applications such as ambiguity in interpretation or producing seismic anomaly in attribute analysis, thus extreme care must be taken both during 188bet vietnam process of performing post-stack seismic merging and during QC and recommendations, as well as during actual usage.
Looking towards 188bet vietnam future, we would like to explore 188bet vietnam implementation of a 3D prestack-premigration merging workflows, which should promise better, more uniform, more seamless merging results, although at a possibly much more expensive computational cost, more complex algorithms/workflows and longer run time.
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