The direct methods (called J-plots) assume that both drain-area formation pressure and bottomhole pressure data is available, at least in select time moments:
In case the drain-area formation pressure is not available the value of Productivity Index can be estimated from:
See Also
Petroleum Industry / Upstream / Production / Subsurface Production / Field Study & Modelling / Production Analysis
[ J-plots ] [ t-weighted J-plot ] [ q-weighted J-plot ] [ Hall Plot ]
[ Inflow Performance Relationship (IPR) ] [ Pressure Transient Analysis (PTA) ] [ Rate Transient Analysis (RTA) ] [ Pressure Deconvolution (DCV) ] [ Capacitance Resistance Model (CRM) ]