Arps Decline Forecast


Spreadsheet

17 rows x 4 columns

fx
A B C D
1 Arps Decline Curve Analysis
2
3 Inputs
4 Initial Rate (qi) 30000 bbl/month
5 Initial Decline (Di) 0.05 1/month
6 b-exponent 0.5 (0=exp, 1=harmonic)
7
8 Production Forecast
9 t (months) q (bbl/month) Np (Mstb) Decline %
10 0 30000 0
11 6 22684.31002 156.5217391 0.2438563327
12 12 17751.47929 276.9230769 0.4082840237
13 18 14268.72771 372.4137931 0.5243757432
14 24 11718.75 450 0.609375
15 36 8310.249307 568.4210526 0.7229916898
16 48 6198.347107 654.5454545 0.7933884298
17 60 4800 720 0.84

Description

Decline curve analysis using the Arps hyperbolic decline equation. Calculates rate and cumulative production over time for production forecasting.

Parameters:

  • qi: Initial production rate
  • Di: Initial decline rate (nominal)
  • b: Hyperbolic exponent (0=exponential, 0.5=hyperbolic, 1=harmonic)

Units: rate is bbl/month against a time column in months, so the cumulative column is a true volume in bbl (shown as Mstb). The Arps functions are unit-agnostic — rate and time must share the same time base or the cumulative is out by the ratio between them.

How to use this blueprint
  1. In Excel, go to the Petroleum Office ribbon tab and click Blueprint Manager
  2. Search for Arps Decline Forecast
  3. Click on the blueprint to preview
  4. Click Insert to place it into your worksheet. Modify the input values to match your data.
Tags:
declineArpshyperbolicexponentialforecastproduction

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