Which of the following option(s) is/are CORRECT for well testing analysis of a reservoir?
Show Hint
- Permeability, skin and reservoir geometry are calculated using data from pseudo steady state.
- Permeability, skin and reservoir geometry are calculated using data from transient state.
- Reservoir geometry is calculated using data from pseudo steady state.
- Absolute open flow potential is calculated from back pressure test for a gas well.
The Correct Option is B, C, D
Solution and Explanation
Step 1: Transient state data.
- During well testing, in the transient state, pressure buildup/drawdown tests are analyzed. - From these, permeability, skin factor, and reservoir radius can be determined. - Hence, (B) is correct.
Step 2: Pseudo steady state data.
- At pseudo steady state, the pressure response stabilizes with time, which helps in estimating reservoir geometry (shape and size). - Therefore, (C) is also correct.
Step 3: Absolute open flow potential (AOFP).
- AOFP for a gas well is calculated from a back-pressure test. - This is a standard reservoir engineering method. - Hence, (D) is correct.
Step 4: Incorrect option check.
- (A) is incorrect because permeability and skin are not calculated from pseudo steady state but from transient state.
Final Answer: \[ \boxed{(B), (C), (D)} \]
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