Prestack Inversion 2016

P-Cube is a pre-stack inversion method developed by Statoil and the Norwegian University of Science and Technology (NTNU). The method computes the probabilities for different lithology-fluid classes from seismic data and geological knowledge.

PCUBE – The probability of hydrocarbons from seismic data

We compute the probabilities for different lithology-fluid classes from seismic data and geological knowledge. The method combines stochastic rock physics relations between the elastic parameters and the different lithology-fluid classes, (Avseth et al., 2005), with the results from a fast Bayesian seismic simultaneous inversion from seismic data to elastic parameters (Buland and Omre, 2003). The methodological development provides a consistent framework for integrating knowledge generated by different disciplines within most oil companies. Thus it enables the maximum synergy.

For P-Cube inversions, you need:

– Litho-Fluid classes from log-measured elastic rock properties
– A background model of multiple zones and A-priori assumptions on likelihood of fingding each LF class by zone
– Partial angle stacks or limited-fold angle gathers
– Wavelets from each angle stack being used in the inversion

The probability of hydrocarbon computed for a prospect offshore Norway

The probability of hydrocarbon computed for a prospect offshore Norway

prestackinversion2

The relation between different lithology-fluid classes and the elastic parameters are based on stochastic rock physics

prestackinversion1

Mapping of Litho-Fluid Classes

prestackinversion4

The match with the probability of hydrocarbons and the structural map

 

Publications

Avseth, P., T. Mukerji, and G. Mavko, 2005, Quantitative Seismic Interpretation: Cambridge University Press.

Buland, A., and H. Omre, 2003, Bayesian linearized AVO inversion: Geophysics, 68, 185-198

Buland, A., Kolbjørnsen, O. Hauge, R., Skjæveland, Ø., and Duffaut, K, (2008) Bayesian lithology and fluid prediction from seismic prestack data: Geophysics 2008 ;Volum 73.(3) s. C13-C21

Riise, O., Elgenes, J., Frey-Martinez, J.M., Kjøsnes, Ø and Buland, A., (2012) Detailed Lithology and Fluid Mapping of the Asterix Gas Discovery Using Bayesian Inversion. Proc. EAGE 2012.