Integration of 3D geo-mechanical effects in petroleum system modelling using a coupled hydro-mechanical simulator

Antoine Bouziat and Daniele Colombo and Jeremy Frey and Nicolas Guy and Marie-Noëlle Woillez and M-C. Cacas and T. Cornu. ( 2016 )
in: 2016 RING Meeting, ASGA

Abstract

Basin models are increasingly used in the Oil&Gas industry to locate potential hydrocarbon reservoirs in sedimentary basins and assess the economic, technological and environmental risks associated to their prospective production. Such models describe the successive sedimentary deposits in the basin and simulate their evolution through geological times, notably in t erms of pore pressure, mechanical stresses and fluid content. However the basin simulators currently used in the industry rely on a simplification of the mechanics involved, considering only the weight of the overlying layers in the stress computation. In this study we investigate the limits of this strong assumption and discuss strategies to integrate 3D geo-mechanical effects in basin modelling workflows. We use an innovative basin simulator prototype, based on an iterative coupling between a finite volume hydro-dynamic code and a finite element mechanical one. With this approach a 3D stress tensor is computed and accounted for in the basin simulation. The value added by the advanced hydro -mechanical coupling is appraised on a 2D synthetic model, represen tative of silico-clastic sedimentation in passive margins. Comparing results between coupled and standard simulations we s uggest that, even in a non- complex structural context, considering 3D stress states can significantly affect fracturing and fluid flow estimates. Starting from this observation, we consider the implications in geo-model construction of running coupled hydro-mechanical simulations on tectonically complex models. We notably address the sensitivity of simulations to the model geometry and d iscuss the significance of mechanical consistency in structural restoration workflows. We also highlight the influence of model meshing and underline the need for methodologies which conciliate fine-scale characterisation of the basin heterogeneities with numerically stable mechanical simulations.

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BibTeX Reference

@INPROCEEDINGS{,
    author = { Bouziat, Antoine and Colombo, Daniele and Frey, Jeremy and Guy, Nicolas and Woillez, Marie-Noëlle and Cacas, M-C. and Cornu, T. },
     title = { Integration of 3D geo-mechanical effects in petroleum system modelling using a coupled hydro-mechanical simulator },
 booktitle = { 2016 RING Meeting },
      year = { 2016 },
 publisher = { ASGA },
  abstract = { Basin models are increasingly used in the Oil&Gas industry to locate potential hydrocarbon
reservoirs in sedimentary basins and assess the economic, technological and environmental risks
associated to their prospective production. Such models describe the successive sedimentary deposits in
the basin and simulate their evolution through geological times, notably in t erms of pore pressure,
mechanical stresses and fluid content. However the basin simulators currently used in the industry rely on
a simplification of the mechanics involved, considering only the weight of the overlying layers in the
stress computation. In this study we investigate the limits of this strong assumption and discuss strategies
to integrate 3D geo-mechanical effects in basin modelling workflows.
We use an innovative basin simulator prototype, based on an iterative coupling between a finite
volume hydro-dynamic code and a finite element mechanical one. With this approach a 3D stress tensor is
computed and accounted for in the basin simulation. The value added by the advanced hydro -mechanical
coupling is appraised on a 2D synthetic model, represen tative of silico-clastic sedimentation in passive
margins. Comparing results between coupled and standard simulations we s uggest that, even in a non-
complex structural context, considering 3D stress states can significantly affect fracturing and fluid flow
estimates. Starting from this observation, we consider the implications in geo-model construction of
running coupled hydro-mechanical simulations on tectonically complex models. We notably address the
sensitivity of simulations to the model geometry and d iscuss the significance of mechanical consistency
in structural restoration workflows. We also highlight the influence of model meshing and underline the
need for methodologies which conciliate fine-scale characterisation of the basin heterogeneities with
numerically stable mechanical simulations. }
}