Relevance of the stochastic stratigraphic well correlation approach for the study of complex carbonate settings: Application to the Malampaya buildup.

Florent Lallier and Guillaume Caumon and Jean Borgomano and Sophie Viseur and Francois Fournier and Christophe Antoine. ( 2011 )
in: Proc. 31st Gocad Meeting, Nancy

Abstract

The stochastic stratigraphic well correlation method is a new technique of uncertainty management for the investigation of the subsurface. It proposes to consider the correlation of well data as a set of possible models. This method samples uncertainties to address the incompleteness of typical subsurface data, e.g. limited seismic resolution, seismic blindness due to the lack of impedance contrast between distinct stratigraphic formations, borehole preferential location, etc. The stochastic stratigraphic well correlation method is applied to the Malampaya buildup (a well documented offshore gas field located North-West of the Palawan Island, Philippines), aged upper Eocene to lower Miocene and developed on the crest of a tiltblock. Among the available data, ten wells, seven of which are cored, have been drilled and a high resolution 3D seismic survey has been acquired by Shell Philippines in 2002. Previous studies highlight that rock petrophysical properties are mainly controlled by diagenesis. Correlation rules are thus developed in order to adapt the stochastic stratigraphic well correlation method to the study of diagenetic units. These rules are based on wireline log shape and diagenetic units type. Results show significant difference with the deterministic correlation model proposed in the literature. Moreover, the stochastically generated correlations are bound with geostatistical methods to build static reservoir models, on which pore volumes are computed. This study allows an estimation of the impact of well correlation on reservoir unit characterization, rock volume assessment and fluid flow modeling. Synthetic seismic profiles are computed from facies models conditioned acoustic impedance models and compared to the effective 3D high-resolution seismic survey. It leads to comparable seismic amplitude images, highlighting the importance of considering several well correlation models for one given seismic survey.

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BibTeX Reference

@INPROCEEDINGS{Lallier3GM2011,
    author = { Lallier, Florent and Caumon, Guillaume and Borgomano, Jean and Viseur, Sophie and Fournier, Francois and Antoine, Christophe },
     title = { Relevance of the stochastic stratigraphic well correlation approach for the study of complex carbonate settings: Application to the Malampaya buildup. },
 booktitle = { Proc. 31st Gocad Meeting, Nancy },
      year = { 2011 },
  abstract = { The stochastic stratigraphic well correlation method is a new technique of uncertainty management for the investigation of the subsurface. It proposes to consider the correlation of well data as a set of possible models. This method samples uncertainties to address the incompleteness of typical subsurface data, e.g. limited seismic resolution, seismic blindness due to the lack of impedance contrast between distinct stratigraphic formations, borehole preferential location, etc.
The stochastic stratigraphic well correlation method is applied to the Malampaya buildup (a well documented offshore gas field located North-West of the Palawan Island, Philippines), aged upper Eocene to lower Miocene and developed on the crest of a tiltblock. Among the available data, ten wells, seven of which are cored, have been drilled and a high resolution 3D seismic survey has been acquired by Shell Philippines in 2002. Previous studies highlight that rock petrophysical properties are mainly controlled by diagenesis. Correlation rules are thus developed in order to adapt the stochastic stratigraphic well correlation method to the study of diagenetic units. These rules are based on wireline log shape and diagenetic units type.
Results show significant difference with the deterministic correlation model proposed in the literature. Moreover, the stochastically generated correlations are bound with geostatistical methods to build static reservoir models, on which pore volumes are computed. This study allows an estimation of the impact of well correlation on reservoir unit characterization, rock volume assessment and fluid flow modeling. Synthetic seismic profiles are computed from facies models conditioned acoustic impedance models and compared to the effective 3D high-resolution seismic survey. It leads to comparable seismic amplitude images, highlighting the importance of considering several well correlation models for one given seismic survey. }
}