DCA (Decline curve analysis)
Decline curve analysis is a means of predicting future oil well or gas well production based on past production history.
Production decline curve analysis is a traditional method of identifying production well problems and forecasting productivity and well life based on real production data. The analysis uses empirical decline models, which have few fundamental justifications. These models are:
- Exponential
- Hyperbolic
- Harmonic
Production decline curve models are applicable for both oil and gas wells.
Hyperbolic decline model is a general view, the other two models are degenerated from the hyperbolic decline model. These three models are linked through the following relative flow rate drop equation (Arps, 1945):
where:
q(t) - flow rate;
qi - initial flow rate;
t - cumulative time since start of production;
b and Di - empirical constants, which should be calculated from the history data.
| Curve type | Rate equation | Cumulative rate equation |
| Exponential decline |  |
 |
| Harmonic decline |  |
 |
| Hyperbolic decline | |
 |
DCA Software
- Tools:ArpsDeclineCurveAnalysis (free!)
- petroleumoffice.com
- OFM
- DSPE
See also
Curtis Whitson Petroleum Engineering Videos#Intro to Decline Curve Analysis
Links
- https://petrowiki.org/Production_forecasting_decline_curve_analysis
- Fetkovich, M. J., Fetkovich, E. J., & Fetkovich, M. D. 1996. Useful Concepts for Decline Curve Forecasting, Reserve Estimation, and Analysis. Society of Petroleum Engineers. http://dx.doi.org/10.2118/28628-PA