Pressure transient survey in injector during the pressure rise period caused by opening well for injection or increasing its injection rate (see Fig. 1):
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Fig 1. Drawdown pressure decline (blue dots) for 2,300 hrs after opening the well for production at 100 m3/d. |
Interpretation
Interpretation of DD is based on:
- visual analysis of PTA diagnostic plot (see Fig. 1)
- selecting pressure diffusion model from PTA Type Library
- fitting selected parameters of pressure diffusion model to pressure gauge data records (see Fig. 2)
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Fig. 1. PTA Diagnostic Plot for vertical well in single-layer homogeneous reservoir with impermeable circle boundary (PSS). Gauge pressure is in blue and log-derivative is in red. | Fig. 2. Pressure diffusion model fitting to pressure gauge data. Gauge pressure is in blue and log-derivative is in red. |
See Also
Petroleum Industry / Upstream / Subsurface E&P Disciplines / Well Testing / Pressure Testing
[ Pressure Transient Analysis (PTA) ][ Pressure Build-Up (PBU) = Build-Up Survey (BUS) ][ Drawdown survey (DD) ]