In the presented work an uncertainty analysis was applied for the unique multilayer field with a complex structure. Main uncertainty parameters as a structural mapping, gas-water contact, petrophysical correlations, lithology distribution were assessed for an influence on reserves and gas production. Much attention was directed to the calculation of structural mapping uncertainties. They were assessed using stochastic modeling – generation of structure error map based on estimated error from seismic data. Each map consists of low and high frequency maps depending on distance from exploration wells. Stochastic algorithm SGS (sequential Gaussian simulation) was performed for the maps construction. Results of the work were applied to determine the influence of the main uncertainty parameters on the production forecast.
This article is dedicated to one of the company's unique oil and gas fields with a complex geological structure, which is in preparation for trial production stage. Productivity is determined in 32 layers (109 accumulations).
The aim of this work is to assess the impact of main uncertainties on forecast level of hydrocarbon production and geological reserves of the field.