The presence of gas hydrate and associated gas in the Makran Accretionary Prism, offshore Iran, has been confirmed by various seismic indicators, including the bottom-simulating reflector (BSR), amplitude blanking, and bright spot. The pre-stack analysis and the study of amplitude-variation-with-offset (AVO) attributes are the most reliable tools for semi-quantitative study of gas hydrate and f...

Measuring reflection amplitude versus offset (AVO) has proved to be effective in reservoir characterization. Experience shows that AVO inversion methods based on amplitude-preserved prestack migration typically provides a more accurate lithology estimate than NMO-based AVO analysis. However, some artifacts may be introduced into the migration section due to an undersampled acquisition geometry,...

avo analysis is a technique which is widely used in industry and is applied on seismic prestack data. results from changes in seismic wave reflection amplitude versus offset can be used in extracting elastic properties and hence lithology and reservoirs pore fluid identification. before performing avo analysis studies, processing steps should be ensured that changes in reflection amplitude are ...

Reflection amplitude as a function of offset is effective in characterizing lithology in oil producing basins. Experience shows that AVO inversion methods based on amplitude-preserved prestack migration typically provides a more accurate lithology estimation than NMO-based AVO analysis. However, some artifacts may be introduced into the migration section, which can obscure the estimate of reser...

We apply three moveout-based methods for multiple suppression to simple synthetic common midpoint (CMP) gathers and compare their performance in terms of level of multiple rejection and, more importantly, in terms of (1) suitability of processed output for use in analysis of amplitude variations with offset (AVO), (2) primary-to-multiple amplitude (p/m) ratio of the data after CMP stacking, and...

The ability to create subsurface images whose amplitudes are proportional the elastic wavefield variations recorded within seismic data as a function of reflection angle is fundamental for performing accurate amplitude-variation-with-offset (AVO) analysis and inversion. A process that generates such commonly referred true-amplitude migration. We have determined how extended subsurface-offset im...

For laterally complex media, it may be more suitable to take a different orientation of thedisplacement vector of Shear-waves. This may change the sign of several imaginary reflections andconversion coefficients to be used in reservoir characterization and AVO (Amplitude Versus Offset)analysis or modeling. In this new convention the positive direction of the displacement vector ofreflected Shea...

The variation in seismic P to P reflection amplitude with offset (AVO) caused by a system of fractures embedded in an isotropic background is investigated. Additionally. a sensitivity analysis of AVO parameters with respect to the fracture system parameters is made. The fracture system is assumed to be aligned vertically or horizontally and can be gas filled or fluid filled. Elastic constants a...

5D interpolation followed by azimuthal prestack migration results in better conditioned gathers for Amplitude Versus Offset (AVO) and Amplitude Versus Azimuth (AVAz) analysis. The data should be prestack migrated prior to AVO or AVAz analysis, but this often proves problematic for land data due to the poor sampling of the data in offset and azimuth. This sparse sampling results in incomplete co...

AVO analysis of seismic data is based on the assumption that transitions in the earth consist of jump discontinuities only. The generalization of this type of transition to a more realistic class of transitions shows a drastic change in observed AVO behavior, especially for the large angles currently attained by increasing cable lengths. We propose a simple approach that accounts for this anoma...