Use this geological calculation for a transparent first-pass interpretation of measured rock, soil, fluid, well, stratigraphic, isotopic, geophysical, or seismic data under an explicitly selected model.

Initial rate (m3/s)

Initial production rate.

Initial decline (1/s)

Nominal decline rate at initial conditions.

Exponent b

Arps hyperbolic decline exponent b.

Time (s)

Producing time since the initial rate.

Evaluate the Arps hyperbolic-decline production rate and cumulative production for a decline exponent between zero and one. The tool evaluates the supplied inputs together and returns the named outputs below; it does not infer omitted operating conditions or change the units shown.^[1]

Rate at time (m3/s)

Production rate after the elapsed time.

Cumulative production (m3)

Cumulative production over the elapsed time.

• Petroleum correlations are fluid-, pressure-, temperature-, and region-dependent. PVT sampling, phase behavior, relative permeability, capillary pressure, heterogeneity, aquifer support, well constraints, history match, and units affect forecasts and reserves.
• Use finite inputs in the displayed units and preserve more precision than the final presentation requires. Independently verify safety-critical, financial, compliance, or production decisions.

Compare independent measurements and models, retain units and analytical metadata, propagate uncertainty, and validate interpretations against logs, cores, maps, laboratory data, or field observations.

• Decline Rate Harmonic Calculator

  Evaluate the Arps harmonic-decline production rate and cumulative production for a unit decline exponent.

• Decline Rate Exponential Calculator

  Evaluate the Arps exponential-decline production rate and cumulative production for a constant decline rate.

• Choke Flow Rate Gilbert Calculator

  Estimate the multiphase liquid flow rate through a production choke with the Gilbert (1954) correlation given upstream wellhead pressure, gas-liquid ratio and choke bore.