Seismic Attribute Categories:
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Examples:
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Comments:
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| P-Wave
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PP reflection Data
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All SAs unless specified
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| S-Wave
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Psv, Mode Converted
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Can give Bi-refringence
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| Pre-Stack
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AVA (Amplitude vs. Angle) AVO (Amp. vs. Offset), Attenuation (Q), Azimuth, stacking Velocities, frequency, scattering, dispersion
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More data intensive; requires more seismic knowledge & analysis; Can yield: direct Hydrocarbon Indicators (DHIs), geo-pressure, anisotropy, pore throat information |
| Post-Stack
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Horizon & Window attributes, Spectral decomposition |
Smaller 3-D Data Volumes, quicker, easier, more common & convenient |
| Single Trace
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Freq., Phase, Amplitude
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Early Attributes, easier to generate and model
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| Multi Trace
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Coherence, Dip, Continuity,
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Useful for Lithology, geo-body, fracture
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| 2-D
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Pre-stack, Post-Stack
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Limited to single trace or 2-D multi-trace
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| 3-D
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Geometric Volumes, Sequence Stratigraphy, Coherency, Azimuth
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The biggest growth area, better well ties, Used w/ visualization & statistical software |
| Time Lapse (4-D)
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Re-shooting 3-D, & Analyzing differences vs. time |
Useful for identifying fluid changes and for Reservoir Simulation matching
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| Mathematical
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Most Attributes: Dip, "Fluid Factor"
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Math function applied to data
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| Extracted
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Horizon or Window Attributes
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Dependent on the horizon interpretation accuracy & calculated attribute volume |
| Wavelet
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StratiMagic®, RSI®
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Wavelet shape can infer facies, in Map or Volume outputs
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SA Analysis methods:
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Examples:
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Comments:
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| Supervised
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Interpreter Input, pattern recognition, Emerge®
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Used more when well data is available, can be used with a probabilistic method.
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| Unsupervised
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Unbiased Mathematics, PCA
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Often an interesting check of assumptions
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| Inversion
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Pre. vs. Post, Model vs. Not
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Many varieties, choose "fit for purpose"
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| Statistics
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Typically SAs are correlated with Well Properties of interest
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Can be very useful IF used correctly, seismic to well ties, modeling, & scaling are critical |
| Neural Networks
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See Figure 2
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One useful method of combining data
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| Principle Component Analysis (PCA)
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Mathematically grouping data by the eignenvalues of the covariance matrix
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Coherent energy~PC1= largest eigenvalue of the Covariance Matrix. Often difficult to understand the physical significance. Can show discontinuities
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| Kohonen, Self Organizing Map (SOM)
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RSIs Lithann® (fig.2), Stratimagic®, SeisClass®, dGBs Detect®
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Another popular and useful method of combining data
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