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The Create Empty Gather module generates a new seismic gather containing traces filled with a constant amplitude value. The gather geometry — that is, the set of trace positions it contains — is derived from an existing geometry object that you supply: a bin grid, a bin collection, a trace header collection, or a point collection. The new gather has no real seismic data; every sample in every trace is set to the fill value you specify.
This module is useful when you need a blank seismic container to receive synthetic data, to use as a template for modelling workflows, or to build a zeroed gather for quality-control purposes. Set the fill value to 0 to produce a zero-amplitude gather, or to any other constant to create a flat DC-level signal across all traces.
This module does not require a seismic data input. Instead, geometry is provided through one of the four optional geometry inputs described in the Parameters section below. Connect only the geometry input that matches your chosen Using Input geometry type selection.
The total number of time samples in each output trace. Together with the Delta time parameter, this determines the time length of the gather: total time length = Samples count × Delta time. For example, 1000 samples at 4 ms per sample gives a 4-second record. The default value is 1. This value must be at least 1.
The time interval between consecutive samples in the output gather, expressed in seconds. This is the sample rate of the created gather. The default value is 0.004 s (4 ms), which is a common acquisition sample interval. Set this to match the sample rate of other data in your project to avoid resampling complications downstream. The value must be greater than zero.
The amplitude value assigned to every sample in every trace of the output gather. The default is 0, which produces a gather with no signal — useful as a blank template. Set this to a non-zero value if you need a constant baseline level across all traces, for example when initialising a gather for synthetic injection or testing display colour bars.
This group of parameters defines which geometry source will be used to determine the trace positions in the output gather. Use the Using Input geometry type selector to choose the geometry mode, then connect the corresponding geometry item to the appropriate input below.
Selects the source of trace positions used to build the output gather geometry. The available options are:
Bin vector (default) — the output traces are generated from an explicit list of bin positions stored in a bin collection item. One trace is created for each bin in the collection. Connect the bin collection to the Input bin collection input.
Bin grid — the output traces cover all inline and crossline positions defined by a 3D bin grid. One trace is created for every (inline, crossline) node within the grid extent. Connect the bin grid to the Input bin grid input. This mode is suitable for creating a full 3D empty volume.
Trace vector — the output gather is built from an existing trace header collection. The geometry (coordinates, inline/crossline numbers, and header values) is copied from the connected trace headers. Connect the trace header collection to the Trace headers input. Use this mode when you want the output to match the exact trace layout of an existing dataset.
Point vector — the output traces are positioned at the XYZ coordinates of points in a point collection. One trace is created for each point. Connect the point collection to the Input point collection input. Use this mode when trace positions are defined by arbitrary surface or subsurface points rather than a regular grid.
Connect a 3D bin grid item here when Using Input geometry type is set to Bin grid. The module reads the inline range, crossline range, and spatial coordinates from this grid to determine the number and positions of output traces. This input is ignored when other geometry types are selected.
Connect a trace header collection (trace vector) here when Using Input geometry type is set to Trace vector. The output gather will contain one trace for each entry in the collection, with geometry copied from the header data. This input is ignored when other geometry types are selected.
Connect a bin collection (bin point vector) here when Using Input geometry type is set to Bin vector. One output trace is created for each bin point in the collection. This is the default geometry mode and is suitable for 2D lines or irregular bin layouts. This input is ignored when other geometry types are selected.
The resulting seismic gather. It contains one trace for each position defined by the input geometry, with each trace having Samples count samples at a sample interval of Delta time, and every sample amplitude set to the specified Filled value. This gather can be passed to any downstream module that accepts a seismic gather, such as synthetic modelling, gather display, or arithmetic operations.