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The Enhance Gathers Geometry Creator is a preparatory module that builds the synthetic trace geometry required by the Multi-Focusing (MF) enhanced-gather pipeline. For each CMP bin in the survey, it collects all real source-receiver pairs whose midpoint falls within a user-defined aperture around that bin, identifies unique virtual source-receiver combinations using a four-dimensional spatial search tree, and outputs a consolidated trace header file representing the idealized acquisition geometry. This synthetic geometry is then used by downstream Data Enhance modules to regularize and interpolate the pre-stack data.
The module works with both 2D (line) and 3D (volume) CMP-sorted geometry and automatically detects which case applies from the connected input headers. It is designed to run in multi-threaded mode, processing all bins in parallel for speed. Note: this module is deprecated and is retained for compatibility with existing workflows. New projects should use the current EG Fold 3D preparation workflow.
Connect the sorted trace headers index item (GGatherIndexVectorItem) derived from your seismic data. The index must be sorted by CMP, either as a 2D line sort or a 3D inline/crossline sort. The module reads the full source and receiver coordinate tables from this item to determine the real acquisition geometry of every trace in the survey. If no valid CMP-sorted headers are connected, the module will report an error and stop.
Sets the spatial merging radius (in metres) used when building the output trace vector. Source and receiver positions that fall within this distance of each other are treated as the same physical point and merged together. This prevents near-duplicate traces from appearing separately in the output geometry. The default value is 500 m. Increase this value if your survey has closely spaced, near-duplicate shot or receiver positions that should be consolidated. Decrease it if you need to preserve fine positional differences between adjacent points.
Defines the search radius (in metres) around each CMP bin centre. All traces whose computed midpoint (the average of the source and receiver XY positions) falls within this radius are included when constructing the virtual geometry for that bin. The default value is 150 m. This parameter also controls how many inline/crossline cells are searched: the module converts the aperture in metres to an integer number of bin steps using the CMP interval parameters below. A larger aperture increases fold but may blend geometry from neighbouring bins; a smaller aperture produces sparser but more localised virtual geometry.
The minimum number of real input traces that must contribute to a candidate virtual source-receiver pair before that pair is accepted and written to the output geometry. The default value is 150 traces. Candidate pairs with fewer contributing traces are discarded. Raising this threshold produces a cleaner, more statistically robust virtual geometry but reduces the number of output traces; lowering it retains more pairs at the cost of including less well-sampled source-receiver combinations. Set this value according to the typical fold of your survey within the chosen aperture.
The physical spacing (in metres) between adjacent CMP bin centres along the inline direction. The default value is 12.5 m. The module divides the Bins Aperture by this value to determine how many inline cells to include in the neighbourhood search for each bin. Set this to match the actual inline CMP interval of your survey. Incorrect values will lead to an aperture that is too large or too small in the inline direction.
The physical spacing (in metres) between adjacent CMP bin centres along the crossline direction. The default value is 25 m. The module uses this value together with the Bins Aperture to compute the number of crossline cells to include in the neighbourhood search. For 2D data, only the inline interval is relevant. Set this to match your survey bin spacing in the crossline direction.
Controls how frequently bins are processed in the inline direction, expressed as a number of bin steps. A value of 1 processes every bin; a value of 5 (the default) processes every fifth bin, skipping four in between. Use a larger step to produce a sparser output geometry for a quick quality-control check, or set it to 1 for a full-density geometry for production processing.
Controls how frequently bins are processed in the crossline direction, expressed as a number of bin steps. The default value is 5, meaning every fifth crossline is processed and four are skipped. As with the inline step, set this to 1 for a full-density output or use a larger value for a faster preview run. For 2D data, only the inline step is applied.
The output virtual trace geometry (GTraceVectorItem) containing the consolidated set of synthetic source-receiver pairs. Each output trace represents a unique, fold-qualified source-receiver combination whose computed midpoint falls within the bin aperture. The source and receiver positions in this item are averaged from all contributing real traces, then shifted so that the resulting midpoint coincides exactly with the bin centre. Connect this output to the input geometry connector of a downstream Data Enhance module (for example, Data Enhance - 3D ZO-MF or Data Enhance - 3D CO-MF).
A read-only counter showing the total number of virtual traces written to the output geometry. This value is updated after execution and provides a quick check of how many source-receiver pairs were retained across the entire survey. If this number is unexpectedly low, consider reducing the Min Fold for Virtual Trace threshold or increasing the Bins Aperture.
A read-only counter showing the total number of CMP bins that were successfully processed and contributed at least one virtual trace to the output. This number reflects the combined effect of the Step Along Inline, Step Along Crossline, and Min Fold thresholds. It is useful for estimating the coverage density of the resulting virtual geometry.
After execution, the Bins map view displays the XY positions of all processed bins as a scatter plot, coloured by the fold of the virtual geometry at each bin location. This provides a spatial overview of where the synthetic geometry was successfully created and allows you to identify areas with low virtual fold that may require parameter adjustments.