Estimation and interpretation of P and S impedance volumes from simultaneous inversion of P‐wave offset seismic data

Abstract

Seismic amplitude variation with offset holds information on density and two elastic parameters: compressional and shear velocities (or impedances). We simultaneously invert multiple offset stacks to transform P-wave offset seismic reflection data to these parameters. Prior to the inversion, wavelets are estimated separately for each offset stack. This enables the inversion to compensate for offset-dependent phase, bandwidth and tuning and nmo stretch effects. The impedance volumes can be interpreted separately or combined to estimate other geophysical parameters which might optimally discriminate between facies. In this regard, we have found the Lame' parameters, Lambda and Mu particularly useful. From well log analysis we expect that reservoir sands have lower Lambda (incompressibility) and higher Mu (rigidity).

Modelo de física de rocas para la interpretación de propiedades petrofísicas de un campo en el Golfo de México

“…A través de diagramas cruzados y otros análisis, las interrelaciones entre las propiedades de la roca y las propiedades del fluido son usadas como guía para modelar el mismo registro usando un modelo de física de rocas. Esto provee de un marco de interpretación que puede ser usado en una posterior inversión sísmica en términos de litologías, fluidos y propiedades de yacimientos [13,14,15].…”

Seismic inversion in the Barnett Shale successfully pinpoints sweet spots to optimize well-bore placement and reduce drilling risks

“…Inversion of seismic data for elastic properties has become a standard part of the workflow for quantitative reservoir characterization. The Simultaneous AVO/AVA inversion process (Pendrel et al, 2000) transforms seismic data from interface to layer properties representing the elastic parameters of the rocks. The results of inversion by G&G data integration allow a more reliable interpretation given the reduced tuning and interference effects and the increased bandwidth compared to the seismic.…”

AVO inversion and Lateral prediction of reservoir properties of Amangi hydrocarbon field of the Niger Delta area of Nigeria

“…Next, Crossplot analysis was applied to evaluate the discriminating power of the elastic logs and their transforms. With the estimated wavelets for each angle stack, velocity model, interpreted seismic horizons and available well control the seismic reflection data were inverted for rock property evaluation, following [4].…”