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The Wavelet generator module creates a synthetic reference wavelet with user-defined shape, dominant frequency, and duration. The generated wavelet can be used as a reference signal in wavelet conversion, well-to-seismic tie, matched filtering, cross-correlation, and convolution modelling workflows. The module outputs a gather containing a single wavelet trace sampled at the specified sample interval.
The available wavelet types cover the most common analytical forms used in seismic processing and modelling: Ricker (first and second derivative of Gaussian), AKB, Berlage, Gaussian, minimum-phase, Klauder, Ormsby, spike, zero trace, and unit trace. For most AVO modelling and well-tie applications, the Ricker1 wavelet is the recommended starting point.
The time sample interval of the output wavelet trace, in seconds. Default: 0.002 s (2 ms). Set this to match the sample interval of the seismic data that will use the wavelet. For example, if the seismic data is sampled at 4 ms, set this parameter to 0.004 s. The total duration of the wavelet in time is Sample ratio multiplied by Number of samples.
The total number of time samples in the output wavelet trace. Default: 800 samples. Combined with the Sample ratio, this determines the total record length (for example, 800 samples at 2 ms = 1.6 s). The wavelet itself is centred within this window. Set the number of samples large enough that the wavelet has decayed to zero before the edges of the trace; for a 40 Hz Ricker wavelet at 2 ms sample rate, 200–400 samples is typically sufficient.
The container grouping the three wavelet shape parameters: Impulse type, Frequency, and Wavelen.
Impulse type — the mathematical shape of the wavelet. Available options: Ricker1 (Mexican hat, second derivative of Gaussian — the standard zero-phase symmetric wavelet for most applications), Ricker2 (fourth derivative of Gaussian), AKB, Berlage, Gaussian, GaussianDeriv, MinPhase (causal minimum-phase wavelet), Klauder (autocorrelation of a linear frequency sweep — used for vibroseis modelling), Ormsby (trapezoid bandpass with linear tapers), Spike (single sample impulse), Zero (all-zeros trace), and Unit (all-ones trace).
Frequency — the dominant (peak) frequency of the wavelet, in Hz. For a Ricker wavelet this is the frequency at which the amplitude spectrum reaches its maximum. Set this to match the dominant frequency of the seismic data. Typical values are 20–80 Hz for conventional reflection surveys.
Wavelen — the total length of the active wavelet window, in seconds. This parameter controls the temporal extent of the analytical wavelet before zero-padding to the full trace length. Set this to at least twice the dominant period (1/Frequency) to capture the full wavelet shape. For a 40 Hz dominant frequency, a value of at least 0.1 s is recommended.
The time position (in seconds) of the wavelet peak within the output trace. Default: 1.0 s. This determines where the centre or maximum amplitude of the wavelet is placed along the time axis. For a Ricker1 wavelet centred at the peak, the wavelet will be symmetric around this time value. Adjust this to position the wavelet at the desired time offset within the trace window.
The peak amplitude value of the output wavelet. Default: 1.0. The wavelet shape is normalised and then scaled so that the maximum sample amplitude equals this value. Set to 1.0 for a unit-amplitude reference wavelet, or adjust to match the amplitude level expected by the downstream module (for example, a matched filter or wavelet conversion step).