Log-log plot of unit-rate drawdown pressure variation and pressure log-derivative
(see Fig. 1 – Fig. 2 for example).
The pressure log-derivative provides a zoomed insight into the pressure diffusion dynamics at different times which helps identifying the pressure diffusion model behind the pressure evolution.
See PTA Type Library for a wide range of typical PTA Diagnostic Plots.
|
|
Fig. 1. PTA Diagnostic Plot for vertical well in single-layer homogeneous reservoir without boundaries. Pressure is in blue and log-derivative is in red. | Fig. 2. PTA Diagnostic Plot for vertical well in single-layer homogeneous reservoir without boundaries. Pressure is in blue and log-derivative is in red. |
