Reserves probabilistic assessment approach involving quantitative geological risks accounting for Achimov deposits with low exploration maturity

Introduction. Recently geological prospecting works become aimed at more complicated perspective objects in terms of their exploration, that leads to higher costs of works. From first stages of exploration, it is necessary to apply integrated approaches while geological analysis & reserves assessment as well as for further works planning considering economic attractiveness of project.
Aim. Main aim is an integrated technical approach development for reserves probabilistic assessment accounting geological risks for Achimov deposits with low exploration maturity.
Materials and methods. This article describes an approach allowing subsequent uncertainties evaluation at three main stages: during structural framework construction, effective thickness estimation and saturation forecast considering possible geological risks.
Results. More than 800 groups of maps were obtained upon the workflow calculation. In each group general, effective and productive volume maps were evaluated as well as fill factor maps. These maps being geologically realistic were used for development strategy planning.
Conclusion. Geologically justified maps at all stages in terms of submarine fans’ conceptual model are obtained upon the workflow calculation. Analyzing the fill factor distribution, application of such approach allows avoiding additional reserves decrease due to the similarity of such distributions estimated by data from analogues. Finally, output maps seem to be suitable for development wells placement and production profiles construction during further reservoir simulation.

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