decon assumptions
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Assumptions while applying decon to seismic dataTRANSCRIPT

Assumption 1. Horizontal layers of constant velocity
Assumption 2. Normal incidence of plane P wave = No shear waves
Assumption 3. Stationary source waveform
Assumption 4. No noise
Assumption 5. Known source waveform
Assumption 6. Random reflectivityWhite process – Appendix B(B8)Autocorrelation = amplitude spectrum
Assumption 7. Minimum-phase wavelet
Deconvolution

Deconvolution SummaryAssumption 1,2,3 : formulating the convolutional model of the 1-
D seismogram
)()()()( tntetwtx
Assumption 4 : eliminates the unknown noise
)()()( tetwtx
Assumption 5 : determine deconvolution
Assumption 6 : the basis for statistical deconvolution
Assumption 7 : provides a minimum-phase

Convolution model
x(t) : recorded seismogram (known)w(t) : basic seismic wavelet (known)* : convolution
e(t) : earth’s impulse response (unknown)
n(t) : random ambient noiseexternal noises – wind, environment,
geophone coupling to groundinternal noises – recording instrument
)()()()( tntetwtx