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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 reflectivity White process – Appendix B(B8) Autocorrelation = amplitude spectrum Assumption 7. Minimum-phase wavelet Deconvolution

Decon Assumptions

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Assumptions while applying decon to seismic data

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Page 1: Decon Assumptions

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

Page 2: Decon Assumptions

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

Page 3: Decon Assumptions

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