Decline curve analysis
Paste a rate history and get an Arps fit — qi, Di and b — with the time to the economic limit, remaining reserves and an EUR.
Production & lift
Gas-lift injection optimisation
Fit a gas-lift performance curve through your injection tests and find both the technical peak and the point where the next MSCF stops paying for itself.
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How it is calculated
- q_oil = a + b·ln(q_inj) + c·ln(q_inj)², fitted by least squares from the 3×3 normal equations.
- The technical optimum is the turning point, exp(−b/2c), where the slope reaches zero.
- The economic optimum is where dq_oil/dq_inj equals gas cost divided by oil price — always at a lower injection rate than the technical peak.
- Available gas, if you set it, caps the recommendation.
Standards it speaks
Where this stops being true
A performance curve fitted from field tests is only valid at the conditions those tests were run in. Raise the separator pressure, cut the water or deepen the injection point and the curve moves. It also assumes the well is stable at every rate, which gas-lifted wells frequently are not — a well heading between two states will give two different rates at the same injection and both will be recorded as tests.
Related tools
IPR curve
One well test turned into an inflow performance curve, a productivity index and an absolute open flow.
Static gradient & bottom-hole pressure
Bottom-hole pressure from a wellhead reading — a liquid gradient for oil and water, and a stepwise gas-column integration for gas.
Build-up test — permeability & skin
A Horner plot from your shut-in pressures, with the semilog slope turned into permeability, skin, p* and flow efficiency.