Earth Sciences Research Journal

Seismologists working on the reflection of seismic data have been dealing with noise and trying to attenuate noise as much as possible without damaging a particular signal. Many methods have been used to removenoise types, each being partially effective. None of the transforms have been ideal and, even at the point of transform, noise becomes added to data. The double density dual tree (DDDT) discrete wavelet transform(DWT) method was used in this paper to attenuate noise in pre-stack and post-stack seismic data.
Wavelet domain ground roll analysis (WDGA) was used for finding ground roll energy in the wavelet domain; it is a substitute method for thresholding in seismic data processing.The DDDTDWT method has four wavelets and two scaling functions. Using this method, shot gather data decomposes to sub-scales and each scale contains coefficients related to a particular signal.The procedure involved applying distinct wavelets and scaling functions to data and then eliminating the coefficient of noise from inverse DDDTDWT using the WDGA technique. The inverse transformprovided a section without noise; double density DWT and dual tree DWT methods were combined (i.e. each method having its own characteristics and advantages).