Fetkovich Decline Curve Analysis

This Excel spreadsheet plots Fetkovich decline curves for gas wells. Decline curve analysis is an empirical procedure that predicts the decline in production rates of gas and oil wells. 

Fetkovich (1968) improved on earlier work by Arps in predicting the declining production rate of oil and gas wells. He suggested that experimental production rate data could be overlaid on a graph and matched to a series of type curves. The production rate is then extrapolated into the future with the assistance of the curves.


The Excel spreadsheet reproduces the plot given in Figure 8 of the following reference.

Fetkovich, M.J., "Decline Curve Analysis Using Type Curves", Journal of Petroleum Technology (June 1980) 1065-77.

The decline curve rate-time equations are given below.
where

  • n is a factor that governs the shape of the back pressure curve
  • qDd is the decline curve dimensionless production rate
  • tDd is the decline curve dimensionless time