EXPLORING PRODUCTION FORECASTING THROUGH DECLINE CURVE ANALYSIS: A PRACTICAL APPROACH USING EXCEL

This project applies Decline Curve Analysis (DCA) using Arps' Exponential,
Hyperbolic, and Harmonic models to forecast oil production rates and support
reservoir management decisions. The analysis is based on an initial production rate
(Qi) of 1000 barrels per day (bbl/day) and a decline rate (Di) of 50% per year,
equivalent to approximately 4.17% per month. The objective is to model production
decline over time and estimate cumulative production, improving the accuracy of
forecasts and enabling better decision-making in reservoir management. Arps’
models are applied to represent different decline behaviours: the Exponential model
assumes a constant decline rate and is simple to apply but may be less reliable for
long-term predictions. The Hyperbolic model allows for a variable decline rate that
adjusts according to reservoir performance, offering more flexible and realistic
forecasts. The Harmonic model, a special case of the Hyperbolic model (where the
hyperbolic exponent b equals 1), provides a smoother, long-term decline trend
suitable for reservoirs with cyclic or intermittent production patterns. Excel is used
as the primary tool for calculations and visualization, where production rates and
cumulative production are computed at regular time intervals using Arps’ equations.
Cumulative production is calculated with the formula, enabling systematic analysis
of time, production rates, and cumulative output. Sensitivity analysis is performed
by varying key parameters such as Qi, Di, and b to evaluate the robustness of the
forecasts. Historical production data, where available, is used for model validation.
The results demonstrate that while the Exponential model is simple, the Hyperbolic
and Harmonic models provide more accurate, adaptable forecasts, highlighting the
importance of selecting an appropriate decline model for effective reservoir
management.
Keywords: Decline Curve Analysis (DCA), Arps Models, Exponential Decline,
Hyperbolic Decline, Harmonic Decline