Multiple-Cycle Production Data Analysis Using Modern Decline Type Curves
C. Johnson and M. Jamiolahmady
Event name: 80th EAGE Conference and Exhibition 2018
Session: Reservoir Management and Field Development I
Publication date: 11 June 2018
Info: Extended abstract, PDF ( 964.47Kb )
Price: € 20
In the interpretation of production data, challenges arise when the data exhibits “anomalies” caused by events such as recompletions, changes in drive mechanism, long-term shut-ins and unusual fluctuations in flow rate and pressure. The method available in literature for resolving such anomalies when using modern decline type curves (MDTCs), which employ material balance time/pseudotime functions, involves a reinitialization approach which is impractical if past production data are unavailable or of low quality. This study, therefore, examines the reliability of a new approach proposed here to reinitialization for MDTC analysis, in which the time after each shut-in period is reset, and the last estimated average reservoir pressure prior to shut-in, with the corresponding fluid properties, is used as the initial condition for the reinitialized cycle. Here historical cumulative production is not employed in the computation of the material balance time function. The approach is verified using multiple-cycle production data (i.e. series of flowing and shut-in periods) generated from 1-dimensional single-well reservoir simulation models, with particular focus on cases with long term shut-ins. The results demonstrate the practicality and reliability of the proposed simple and efficient approach for the analysis of individual production cycles to reliably estimate reservoir and well productivity parameters.