Lab 4: Seismic Deconvolution

The aim of seismic deconvolution is to increase the vertical resolution of the data by compressing the source wavelet (to a zero-phase spike, if possible) This is known as spiking deconvolution. Not only that, seismic deconvolution also aims to attenuate noise such as multiples elimination. For this, we need to define the seismic convolution model. 

To perform spiking deconvolution, we need to set 3 parameters namely:

a) Auto-correlation window (w)
b) Filter length (N)
c) Percent pre-whitening 


1. Call and display for seismic shot gather no. 4-6 as shown in figure below before applying spiking deconvolution. 


Figure 1

Figure 2: Shot gathers:4,5 and 6 before applying spiking deconvolution



2. Performing Auto-correlation

Figure 3: Auto-correlograms of shot gather number 4,5 and 6.



3. Applying spiking deconvolution

The aim of spiking deconvolution is to compress the source wavelet into zero-phase spike of zero width. This means that we are eliminating the effect of source wavelet and only remain the Earth’s reflectivity in the seismogram. Based on Figure 4, it can be seen that the data became spiker.

Figure 4: Shot gather 4,5 and 6 after applying spiking deconvolution


4. Analyze further in the spectrum domain via the power spectral density of the average traces

Figure 5: PSD of the average trace of shot gathers 4,5 and 6 before and after spiking deconvolution


5. Apply AGC with window length of 0.5 s to the deconvolved data as in Figure 6. AGC is applied to compensate for the lost amplitudes after deconvolution 

Figure 6: Shot gather 4,5, and 6 after applying deconvolution and instantaneous AGC





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