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The Simple anizotropic modeling by Trace headers module generates synthetic seismic shot records by convolving a source wavelet with a travel-time model computed from a user-defined anisotropic (VTI) depth layered model. Source and receiver positions are read directly from the trace header vector, allowing the module to simulate realistic acquisition geometries without manually specifying source or receiver grids. The travel-time computation accounts for anisotropy through Thomsen-style eta and epsilon parameters specified per depth layer.
Use this module to create forward-modelled synthetic data for anisotropic velocity model quality checking or as a reference dataset for residual analysis in near-surface statics workflows. This module is deprecated; consider using a more current modeling module for new projects.
Boolean flag. When enabled, source and receiver coordinates are treated as full 3D (X, Y, Z). Disable for 2D line geometry where only the inline coordinate is meaningful. Default: enabled.
Link to the trace header vector containing source and receiver positions for all traces to be modelled. The module reads each trace's geometry from these headers to position the modelled shot and receiver correctly in the anisotropic velocity model.
Link to the seismic wavelet gather used as the source signature for convolution. If no external wavelet is connected, the synthetic wavelet defined by the WaveParams parameter group is used instead.
Length of each output synthetic trace in samples. Default: 1000 samples. The total record length in milliseconds is equal to Number of samples multiplied by Sample rate. Ensure this is long enough to capture the deepest reflection of interest.
Time sampling interval (s) of the output synthetic traces. Default: 0.004 s (4 ms). This should match the sample rate of the field data to which the synthetics will be compared.
When enabled, the module ignores topographic elevation differences between sources and receivers and models all positions at a flat datum. Default: enabled. Disable when surface topography is significant and you want the modelled travel times to include the effect of elevation variations.
Path to the output SEG-Y file where the synthetic shot records will be saved. The file will be written in standard SEG-Y format. Specify a full file path including the .sgy extension.
Container group defining the spatial grid parameters of the internal velocity model used for travel-time computation. These values set the extent and resolution of the model in all three spatial dimensions.
Maximum source-receiver offset (m) for which the travel-time model is computed. Default: 5000 m. Set this to the maximum offset present in the trace headers. Traces at offsets beyond this value will not be modelled.
Inline (X) spatial grid step (m) of the internal travel-time model. Default: 10 m. Finer steps increase travel-time accuracy but require more memory and computation time.
Crossline (Y) spatial grid step (m) of the internal travel-time model. Default: 10 m. For 2D surveys set this equal to dx or set 3D case to disabled.
Vertical (depth) grid step (m) of the internal travel-time model. Default: 10 m. This controls the depth resolution at which velocity transitions between layers are resolved.
Container group defining the synthetic source wavelet used for convolution when no external wavelet is connected. Contains the wavelet type (ImpulseType), dominant frequency (Hz), and total wavelet length (s). Set the dominant frequency to match the expected peak frequency of the field data.
Table defining the horizontally layered anisotropic (VTI) velocity model. Each row specifies one depth layer with the following columns:
Depth — base depth (m) of the layer. Default: 1000 m.
Velocity — vertical P-wave velocity (m/s) of the layer. Default: 2000 m/s.
eta — Thomsen anisotropy parameter eta controlling the non-hyperbolic moveout of reflections at large offsets. Default: 0 (isotropic). Typical values range from 0 to 0.2 for sedimentary rocks.
epsilon — Thomsen anisotropy parameter epsilon representing the fractional difference between horizontal and vertical P-wave velocities. Default: 0 (isotropic).
Selects whether the module executes on the CPU or an available GPU.
Enables distributed processing across multiple compute nodes in a cluster.
Minimum number of traces dispatched to each compute node per batch during distributed execution.
When enabled, limits the number of threads used on each cluster node to the value set in Number of threads.
Optional text appended to the distributed job name to distinguish this run in the cluster queue.
When enabled, allows manual assignment of CPU core affinity for processing threads via the Affinity parameter.
CPU core affinity mask applied when Set custom affinity is enabled.
Number of CPU threads used for parallel execution. Set to the number of available physical cores for best performance.
When enabled, the module passes data through unchanged without performing any modeling. Use this to temporarily disable the module in a workflow without disconnecting it.
Travel-time vector item containing the modelled first-arrival travel times for all source-receiver pairs. This output can be connected to a statics module or a first-break QC display to compare synthetic and observed travel times and evaluate the anisotropic model quality.