Integrated inverse method to estimate virgin stress state in reservoirs and overburden

Antoine Mazuyer and Paul Cupillard and Richard Giot and Marianne Conin and Pierre Thore. ( 2017 )
in: 79th EAGE Conference & Exhibition, EAGE, Paris, France

Abstract

Stress estimation in reservoirs and overbuden has become a key point during the exploration and the exploitation of the oil ans gas fields. We propose in this abstract an integrated method to estimate a physically admissible (i.e. satisfying the equilibrium equations) 3D stress field in whole geological models. Stress field is computed using a simple elastic behavior and it is constrained to the wellbore data using an inverse approach. Forward problem is solved using a Finite Element Analysis. The model parameters to invert are the Neumann conditions which are assumed to be piecewise linear functions along the vertical direction. The data parameters are stress observations which came from the hydraulic fracturing and the borehole breakouts. Misfit between the computed stress and the observed stress is minimized using the CMA-ES algorithm. The method is tested with a synthetic case by taking a stress field computed with the Limit Analysis method as reference. The inversion results show that the method is able to well retrieve the stress variation in the geological model.

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BibTeX Reference

@INPROCEEDINGS{mazuyerEAGE2017,
    author = { Mazuyer, Antoine and Cupillard, Paul and Giot, Richard and Conin, Marianne and Thore, Pierre },
     title = { Integrated inverse method to estimate virgin stress state in reservoirs and overburden },
     month = { "jun" },
 booktitle = { 79th EAGE Conference & Exhibition },
      year = { 2017 },
  location = { Paris, France },
organization = { EAGE },
       doi = { 10.3997/2214-4609.201700935 },
  abstract = { Stress estimation in reservoirs and overbuden has become a key point during the exploration and the exploitation of the oil ans gas fields. We propose in this abstract an integrated method to estimate a physically admissible (i.e. satisfying the equilibrium equations) 3D stress field in whole geological models. Stress field is computed using a simple elastic behavior and it is constrained to the wellbore data using an inverse approach. Forward problem is solved using a Finite Element Analysis. The model parameters to invert are the Neumann conditions which are assumed to be piecewise linear functions along the vertical direction. The data parameters are stress observations which came from the hydraulic fracturing and the borehole breakouts. Misfit between the  computed stress and the observed stress is minimized using the CMA-ES algorithm. The method is tested with a synthetic case by taking a stress field computed with the Limit Analysis method as reference. The inversion results show that the method is able to well retrieve the stress variation in the geological model. }
}