Arps Segmented Decline

Arps Segmented Decline is a forecaster composed of two segments each characterized by a particular type of classic Arps Decline Curves. Albeit this behavior was never observed on actual wells, this method was created with the purpose of limiting EUR forecasts, in particular in non conventional fields.

Forecaster parameters:

  • min and max fitting period: allows to focus on the last period or the overall well trend, expressed in months.

  • b range: b_min and b_max used to perform automatic fit on the hyperbolic segment. It could be set between 0 and 3.

  • Terminal decline: minimum value of Arps decline before starting exponential segment, expressed in %loss of potential per year. Only one single value for the whole field can be applied.

  • Minimum fit quality (R2) - minimum R2 between fitted points and real data

  • D parameter range (minimum and maximum D parameters - to avoid too flat curve or unrealistic decline.

In the example below, the transition between the hyperbolic segment and exponential segment is displayed, taking place when the instantaneous decline reaches the value 10%.

Transition from hyperbolic to exponential segment

Arps segmented decline is only available for gas.

For more information on the Arps Segmented Decline: