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Export ZO-MF results reads a Zero-Offset Multi-Focusing (ZO-MF) parameter database (.kdb file) computed by the ZO-MF search engine and exports the stored attributes as seismic gather files (.gsd format). Each selected attribute type is written to a separate output file, allowing you to inspect, quality-check, or carry individual MF attributes forward into subsequent processing steps.
The module supports both 2D and 3D ZO-MF databases. Connect exactly one storage file — either the 2D or the 3D input — before running. An optional velocity corridor (GMFPickingItem) can be supplied to restrict the export to a picked velocity range. You choose which MF attribute types to export by enabling the corresponding toggles in the Types group; by default only the stacked image is exported.
Note: This module is marked as deprecated. It is retained for backward compatibility with existing workflows. For new projects, consult the current MF export utilities.
Path to the 2D ZO-MF parameter database file (.kdb) produced by the 2D ZO-MF search engine. Connect this item when your survey is a 2D seismic line. Leave it disconnected if you are working with a 3D database. Only one of Storage file 2D or Storage file 3D may be connected at a time; connecting both will cause an error at execution.
Path to the 3D ZO-MF parameter database file (.kdb) produced by the 3D ZO-MF search engine. Connect this item for 3D surveys. When a 3D database is connected, the inline and crossline range parameters in the Create Params group become active and allow you to restrict the export to a spatial subset of the volume.
Optional velocity corridor item (G3DPickingItem) that defines a picked velocity-semblance corridor. When provided, the exporter uses this corridor to guide attribute selection from the MF parameter table, restricting the exported values to those that fall within the corridor boundaries. This is the same picking item used during the ZO-MF search and data enhancement steps. If not connected, attributes are exported without a velocity constraint.
Base path and filename for the output gather files (.gsd). One file is written per enabled attribute type. The module automatically appends a suffix to the base name for each attribute (for example, output_stack.gsd, output_correlation.gsd, and so on). Ensure the target directory has sufficient disk space to hold all selected attribute volumes.
This parameter group controls how the MF attribute image is assembled from the multi-directional ZO-MF results stored in the database. It contains the following sub-parameters:
Directions (integer, default 1, minimum 1): Number of azimuth sectors used when combining MF results from multiple directions into a single image. Increasing this value enables multi-directional stacking, which can improve the signal-to-noise ratio on azimuthally anisotropic data.
From angle (degrees, default -90): Starting azimuth angle of the direction range to include. Set this together with To angle to select a specific azimuth sector for image creation.
To angle (degrees, default 90): Ending azimuth angle of the direction range. The full range -90 to 90 encompasses all azimuths and is suitable for isotropic surveys.
SN enhance (boolean, default false): When enabled, applies an additional signal-to-noise enhancement step during image assembly, using the correlation semblance to suppress low-coherence contributions.
Correlation threshold (percent, default 10%, range 0-100%): Minimum semblance value that a direction contribution must exceed to be included in the image. Contributions with semblance below this threshold are suppressed. Active only when SN enhance is enabled.
Min angle distance selection (integer, default 1, minimum 1): Minimum angular separation (in index steps) between selected directions. Increasing this value enforces greater angular diversity when picking the best-fitting directions from the MF table.
Min radius distance selection (integer, default 100, minimum 1): Minimum radius separation (in index steps) between selected MF parameter solutions. This prevents closely spaced duplicate solutions from being combined, ensuring that each contributing direction represents a genuinely distinct wavefront parameter set.
Controls how the module writes the output files when files with the same name already exist. Options:
Direct (default): Overwrites any existing output files from scratch. Use this when running the export for the first time or when you want to completely replace previous results.
Append: Adds new data to the end of any existing output files rather than overwriting them. Use this when extending a previous export with additional lines or bins without re-exporting data already written.
This group defines spatial and time-domain constraints that control which part of the MF database is exported. It contains the following sub-parameters, some of which apply only to 3D databases.
First inline number to export from the 3D MF database. Set to -1 (the default) to begin at the first available inline in the database. Applies only when a 3D storage file is connected. Use this together with 3D To Inline to export a subset of inlines from a large volume, which can save time and disk space during quality-control checks.
Last inline number to export from the 3D MF database. Set to -1 (the default) to include all inlines through to the last available inline in the database. Applies only when a 3D storage file is connected.
First crossline number to export from the 3D MF database. Set to -1 (the default) to begin at the first available crossline. Use in combination with 3D To Crossline to define a rectangular spatial window within the 3D survey area.
Last crossline number to export from the 3D MF database. Set to -1 (the default) to include all crosslines through to the last available crossline in the database.
When enabled, applies a time shift to each exported trace so that the seismic reference level matches the specified Datum elevation. Default is false (no datum shift applied). Enable this when the MF database was computed relative to a floating datum and you need the exported data to reference a fixed datum elevation, for example to match other seismic data in the project.
When enabled, bins that contain no data in the MF database are written as zero-amplitude traces rather than being skipped. Default is false. Enable this when downstream processing requires a regular, fully populated gather (for example, certain 3D visualization or inversion tools that expect a complete inline/crossline grid).
Reference elevation (in meters) to which exported traces are shifted when ShiftToDatum is enabled. Set this to the project datum elevation. This parameter has no effect when ShiftToDatum is disabled.
This group contains output formatting options that control how attribute values are written to the exported files.
When enabled, zero-valued samples in velocity attribute outputs (V Slow, V Fast, VSlow/cos(Dip), VFast/cos(Dip)) are suppressed and not written. Default is false. Enable this if zero velocities in empty or under-sampled bins would corrupt downstream velocity modeling or interpolation.
When enabled, the trace order within each output gather is reversed. Default is false. This may be needed when the MF database was built with a particular trace-ordering convention that differs from the convention expected by the downstream application receiving the exported data.
When enabled, depth and distance attribute values are converted from meters to feet before being written to the output files. Default is false. Enable this when the project or receiving application uses imperial units.
This group contains one boolean toggle for each MF attribute type available in the database. Enable the checkboxes for every attribute you want written to disk. Each enabled attribute is written to a separate .gsd file. Disabling an attribute reduces execution time and disk usage. The available attribute types are described below.
Boolean toggle, default true. Exports the ZO-MF zero-offset stack image. This is the primary imaging result of the MF workflow — the coherency-weighted stack of all traces focused to a common reflection point. This is the only attribute enabled by default and is typically the most important output for seismic interpretation.
Boolean toggle, default false. Exports the semblance (correlation) attribute — a measure of wavefield coherency at each bin and time sample. High semblance values indicate well-focused, coherent reflections. This attribute is useful for quality-control of the MF search results and for creating coherency-based masks.
Boolean toggle, default false. Exports the emergence angle attribute — the angle at which the wavefront arrives at the surface, derived from the best-fitting MF parameters. This attribute is used in azimuth analysis, AVO studies, and to estimate local dip and structure.
Boolean toggle, default false. Exports the Gamma parameter — the ratio between the normal-incidence point (NIP) wavefront radius and the normal wavefront radius. Gamma is one of the three fundamental Multi-Focusing wavefront parameters and carries information about the subsurface velocity distribution and reflector curvature.
Boolean toggle, default false. Exports the CRE (Common Reflection Element) radius parameter — the NIP wavefront radius of curvature for the primary inline direction. CRE parameters are used to reconstruct subsurface geometry and to perform MF-based tomographic velocity analysis.
Boolean toggle, default false. Exports the CRE2 parameter — the NIP wavefront radius of curvature for the secondary (crossline) direction in 3D surveys. Together with CRE, CRE2 enables full 3D characterization of the NIP wavefront geometry.
Boolean toggle, default false. Exports the azimuth angle of the CRE wavefront principal axis in 3D surveys. This attribute indicates the dominant structural orientation of the reflector and is useful for azimuthal anisotropy analysis.
Boolean toggle, default false. Exports the CEE (Common Evolution Element) radius parameter — the normal wavefront radius of curvature for the primary inline direction. CEE parameters capture the large-scale curvature of the wavefront and complement the CRE parameters in the MF wavefront description.
Boolean toggle, default false. Exports the CEE2 parameter — the normal wavefront radius of curvature for the secondary (crossline) direction in 3D surveys. Together with CEE, CEE2 provides a complete 3D description of the normal wavefront curvature.
Boolean toggle, default false. Exports the azimuth angle of the CEE wavefront principal axis in 3D surveys. As with CRE Azimuth, this attribute is useful for analyzing structural orientation and azimuthal wavefront asymmetry.
Boolean toggle, default false. Exports the V Slow attribute — the near-surface wavefront slowness velocity (m/s) derived from the MF parameters. V Slow represents the apparent velocity of the wavefront along the slower principal direction of propagation. It is used in statics computation and near-surface characterization.
Boolean toggle, default false. Exports the V Fast attribute — the near-surface wavefront velocity (m/s) along the faster principal propagation direction. Together with V Slow, V Fast describes the elliptical near-surface velocity anisotropy encoded in the MF wavefront parameters.
Boolean toggle, default false. Exports the reflector dip angle (degrees) at each bin and time sample, as computed from the MF emergence angle parameters. This attribute provides a direct measure of structural dip and can be used as input to dip-guided filtering, structure extraction, or horizon-consistent attribute analysis.
Boolean toggle, default false. Exports the dip azimuth angle (degrees) — the direction in the horizontal plane toward which the reflector dips, derived from the 3D MF emergence angle parameters. Azimuth Dip is complementary to the Dip attribute and together they fully characterize the 3D reflector orientation.
Boolean toggle, default false. Exports the dip-corrected slow velocity attribute — V Slow divided by the cosine of the local reflector dip angle. This correction accounts for the geometric projection of the wavefront velocity onto the horizontal plane, yielding a dip-independent velocity estimate that is more suitable for lateral velocity comparisons and statics modeling.
Boolean toggle, default false. Exports the dip-corrected fast velocity attribute — V Fast divided by the cosine of the local reflector dip angle. Use this attribute for the same purposes as VSlow/cos(Dip), but for the fast propagation direction. Comparing VSlow/cos(Dip) and VFast/cos(Dip) can reveal azimuthal velocity anisotropy independent of structural dip effects.
Boolean toggle, default false. Exports the fold attribute — the number of traces that contributed to the MF stack at each bin. High fold indicates good data coverage; low fold indicates sparse or irregular illumination. Inspect this attribute to identify acquisition gaps, edge effects, or areas where MF results may be unreliable due to insufficient trace count.