Influence of low frequencies on seismic impedance inversion

Abstract

Acoustic impedance is a rock property that can be derived from seismic data and contains important information about subsurface properties. Mathematically, the acoustic impedance can be calculated from earth’s reflectivity function and this function can be estimated from seismic data. However, estimation of reflectivity from seismic data even after excellent data processing, is always very bandlimited, lacking both low and high frequencies. In this situation, recovering any of this bandwidth, especially low frequencies, can be helpful. The thesis will be focused on recovering low frequencies to improve impedance estimation and this includes trying to improve a frequency domain deconvolution algorithm using different smoother types and correcting the whitening error of deconvolution operator using color operator. At the end, the maximum correlation results between acoustic impedance inversion and well impedance demonstrate using color operator can increase the maximum correlation by around 20 percent comparing with the result without using color operator.