The depletion plan in the ACG field complex in Azerbaijan requires a good understanding of the production and injection allocation both geographically as well as by formation. A reliable quantification of the conformance of the injection volumes both in gas as well as in water injectors is critical for attaining excellence in the management of the reservoir. Short term operational and long term strategic decisions are significantly better informed by having a calibrated method of calculated permeability and productivity based on core and logs.
Such a method has been developed for ACG in Azerbaijan. The method has been tested successfully on the field after comparing predicted rates with values resulting from pressure transient analysis. The method involves the generation of porosity-permeability predictive trends for the producing formations using core data. These trends have been validated using pore system models which use petrographic descriptions as inputs. Similarly, log derived permeabilities have been succesfully calibrated to well production tests, after pressure transient analysis.
The method has proven robust when used in predicting well rates. PI's calculated by using log derived properties have been consistent with actual rates in the producers in Azeri.
As a result, production is routinely allocated on the basis of cumulative log-derived permeability in the commingled wells, and has been successfully calibrated to Distributed Temperature Sensors data across producing reservoirs. Finally, PI's as derived from 01-1 logs are used for mid term production forecasting.