For field exploration planning with the purpose to achieve balance between investments and receiving information it is necessary to estimate geological risks and define zones of geological uncertainty. Obviously low data quantity and quality leads to higher uncertainty of parameters and reserves estimation. Moreover, geological objects with the same data density but different geneses have different range of uncertainty. This fact highlights the need to add one more variable to estimation – geological complexity, which represents integration of geological features for the studied object. The methodology, described in this article, allows mapping a geological confidence (analogue of variation map, but without multiple geological 3D realizations). The confidence map considers combination of data density maps (quantity and quality of investigation) and geological complexity maps (lateral and vertical heterogeneity) of the following volumetric parameters: porosity, net pay thickness, oil production area, oil saturation. The values of confidence range from 0 to 1, where 0 – minimum confidence (maximum of uncertainty), 1 – maximum confidence (minimum of uncertainty). Confidence equals to 1 characterizes full number of well and field investigations for particular parameter. One of the advantages of this approach is the possiblity to identify the source of uncertainty – lack of data or high complexity of geological characteristic that is required to be explored. Visualization volumetric parameters confidence in 2D allows appraise the areas with minimum and maximum uncertainty and risk on the particular target and plan actions to deal with them.
References
1. Fofanova E.A., Pavel’eva Yu.N., Mel’nikova O.A. et al., Geological data density (In Russ.), PRONEFT’’. Professional’no o nefti, 2022, V. 7, no. 1, pp. 22–29, DOI: 10.51890/2587-7399-2022-7-1-22-29
2. Fofanova E.A., Pavel’eva Yu.N., Mel’nikova O.A. et al., Quantitative assessment of areal geological complexity (In Russ.), PRONEFT’’. Professional’no o nefti, 2021, V. 6, no. 4, pp. 54–61, DOI: 10.51890/2587-7399-2021-6-4-54-61
