What is Ricker wave? The Ricker wavelet is the second derivative of a Gaussian function. Theoretically, it is a solution of the Stokes differential equation, including the effect of Newtonian viscosity (Ricker 1943, 1944). It
What is Ricker wave?
The Ricker wavelet is the second derivative of a Gaussian function. Theoretically, it is a solution of the Stokes differential equation, including the effect of Newtonian viscosity (Ricker 1943, 1944). It is applicable to seismic wave propagation through viscoelastic homogeneous media, that is the Voigt model.
What do you mean by wavelet?
From Wikipedia, the free encyclopedia. A wavelet is a wave-like oscillation with an amplitude that begins at zero, increases, and then decreases back to zero. It can typically be visualized as a “brief oscillation” like one recorded by a seismograph or heart monitor.
What is Mexican hat filter?
A Mexican hat function-based operator is used for image feature detection, including the local area detection and the feature point detection. For the local area detection, we use the Mexican hat operator for image filtering, and then the zero-crossing points are extracted and merged into the area borders.
What is wavelet in seismic?
The seismic wavelet is the link between seismic data (traces), interpretations and the geology (reflection coefficients). It must be accurately known (estimated or measured) and quantified in all stages of the seismic cycle (from modelling, acquisition, processing, interpretation, inversion and reservoir work).
What is a zero phase wavelet?
A zero phase wavelet is symmetrical with a maximum at time zero. Zero phase wavelets have energy before time zero, which makes them noncausal, and therefore they are not physically realizable.
What is difference between wave and wavelet?
Wave is an oscillating function of time or space and is periodic. In contrast, wavelets are localized waves. They have their energy concentrated in time and are suited to analysis of transient signals. Compare wavelets with sine waves, which are the basis of Fourier analysis.
Why DWT is used?
The DWT decomposes your signal into “sub-bands”. Depending on the number of levels in your filter bank, your input signal is split into bands covering different frequency ranges. So each level simultaneously splits the signal into high and low frequency components. That’s why DWT can be used e.g. for noise filtering.
What is the Mexican hat called?
sombrero, broad-brimmed high-crowned hat made of felt or straw, worn especially in Mexico and the southwestern United States. The sombrero, its name derived from the Spanish word sombra, meaning “shade,” first appeared in the 15th century.
Why is Gaussian different?
Blurring an image using a Gaussian kernel suppresses only high-frequency spatial information. Subtracting one image from the other preserves spatial information that lies between the range of frequencies that are preserved in the two blurred images.
What is wavelet length?
To examine the effect of wavelet length, we vary the length of the filter from a minimum of 2 to a maximum of 24. Note that the Daubechies Least Asymmetric family is only defined for lengths greater than or equal to 8, and the Coiflet family is only defined for lengths that are multiples of 6.
What is a minimum phase wavelet?
The minimum phase wavelet has a short time duration and a concentration of energy at the start of the wavelet. It is zero before time zero (causal). An ideal seismic source would be a spike (maximum amplitude at every frequency), but the best practical one would be minimum phase.