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The Seismic attributes 3D distributed module computes a comprehensive suite of instantaneous seismic attributes from a 3D post-stack volume. It reads the data directly from a SEG-Y file, computes each selected attribute trace-by-trace using the complex trace (Hilbert transform) method, and writes the results as separate per-attribute output files in the specified output folder. The module supports distributed (multi-node) execution for efficient processing of large 3D datasets.
For attributes that require spatial context (Coherence, Similarity, Chaos, Seismic relief), a configurable trace window determines how many neighbouring traces are included in the calculation. All 17 attributes can be enabled or disabled individually, so only the required outputs are computed.
The handle to the 3D post-stack seismic volume from which attributes will be computed. Connect to the output handle of the Open SEG-Y module. The entire volume is read into a trace header index before processing begins.
A group of checkboxes selecting which attributes to compute and save. All 17 attributes are enabled by default. Disable any attribute that is not required to reduce computation time and output file storage. The available attributes are:
Instantaneous amplitude (reflection strength). Represents the total energy at each time sample independent of phase or polarity. Used to identify bright spots, gas anomalies, and stratigraphic features such as channel sands.
The first time derivative of the envelope. Highlights sharp transitions in reflection strength, making it sensitive to the top and base of strong reflectors and thin-bed boundaries.
The second time derivative of the envelope. Provides even greater sensitivity to rapid changes in reflection strength than the first derivative. Used for very thin-bed detection and high-resolution stratigraphic analysis.
The angular position of the seismic waveform at each sample, independent of amplitude. Effective for tracing reflector geometry and continuity, fault detection, and identifying unconformities without amplitude bias. Range: -π to +π.
The cosine of the instantaneous phase, which maps the cyclic phase values onto a smooth continuous scale. Useful for phase-based structural visualisation without the phase-wrap discontinuities that appear in the raw instantaneous phase. Range: -1 to +1.
The instantaneous phase with phase wraps removed, producing a monotonically increasing phase trace. This provides a measure of accumulated phase with depth and is used in inversion and wavelet analysis applications.
The rate of change of instantaneous phase with time. Sensitive to bed thickness, fluid effects, and seismic attenuation. Low-frequency anomalies may indicate gas or highly attenuating zones. The range corresponds to the signal bandwidth of the input data.
The first time derivative of instantaneous frequency (instantaneous frequency acceleration). Highlights rapid changes in local frequency content and is used for high-resolution thin-bed and stratigraphic boundary detection.
The dominant (peak spectral) frequency estimated locally over a short time window. Provides a more robust frequency estimate than instantaneous frequency in noisy data and is used to track lateral frequency changes across the survey.
The local spectral width (bandwidth) of the seismic signal at each sample. Narrow bandwidth indicates a tuned monochromatic signal (e.g., thin-bed resonance); broad bandwidth indicates a broadband reflector. Used for thin-bed analysis and reservoir characterisation.
A composite attribute sensitive to thin-bed tuning effects. High values indicate locations where bed thickness approaches the tuning thickness. Used to identify thin reservoir intervals below conventional seismic resolution.
An estimate of the local seismic quality factor (Q), which measures how rapidly seismic energy is attenuated with depth. Low Q values indicate high-attenuation zones such as gas-saturated sediments. Used for fluid detection and lithological characterisation.
The signed amplitude of the seismic trace at each sample. This is identical to the input data value and serves as a reference attribute for comparison with the computed instantaneous attributes.
A measure of trace-to-trace similarity in the spatial window defined by the Trace window parameter. Low coherence values highlight structural discontinuities such as faults, fractures, and channels. Requires the Trace window parameter to define the lateral extent of the comparison.
A normalised cross-correlation between adjacent traces used to measure waveform similarity. Similar to coherence but computed using a different algorithm that may give better results in areas of low signal-to-noise ratio.
The inverse of coherence or similarity, highlighting zones of chaotic or disturbed reflectivity. High chaos values indicate deformed, disrupted, or incoherent seismic facies such as mass-transport complexes, gas chimneys, or heavily faulted zones.
A structural dip and azimuth-sensitive attribute that highlights lateral changes in reflector orientation and dip magnitude. Used for structural mapping of subtle dip variations and for illuminating stratigraphic traps in low-relief environments.
The length of the time window (in seconds) used for multi-trace attribute computations (Coherence, Similarity, Chaos, Seismic relief, Dominant frequency). Larger windows produce smoother results but reduce vertical resolution. Default: 0.1 s.
The number of neighbouring traces included on each side of the central trace in lateral attribute computations. A window of 3 uses the 3 nearest neighbours in each direction. Larger values improve signal-to-noise in the attribute but reduce lateral resolution. Default: 3 traces.
The reference NMO or replacement velocity (in m/s) used internally for dip-compensated attribute computations. For post-stack data, set this to a representative interval velocity for the target zone. Default: 2000 m/s.
The directory path where the output attribute files will be written. One output file is created per enabled attribute. The files are named automatically using the attribute name as a suffix. Ensure sufficient disk space is available for all selected attributes.
Parameters configuring distributed (multi-node) execution on a processing cluster.
The number of traces processed as a single task unit when the job is distributed across multiple compute nodes. Larger bulk sizes reduce communication overhead but may cause uneven load balancing across nodes.
The maximum number of CPU threads allowed per compute node during distributed execution. Set this to match the available CPU cores per node while leaving capacity for other processes.
An optional suffix appended to the distributed job name to distinguish multiple simultaneous distributed jobs running on the same cluster.
The number of CPU threads used for local multi-threaded processing. Set this to the number of physical CPU cores available on the processing machine. A higher thread count reduces computation time for large volumes.
When enabled, this module is bypassed during workflow execution without being removed from the workflow. Use this to temporarily disable attribute computation while keeping the module configured for later use. Default: disabled.