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: \[ \boxed{(B), (C), (D)} \]
Four different multilateral well patterns (Forked, Branched, Dual opening and Splayed) are shown in the figure. Which ONE of the following options correctly identifies the multilateral well patterns?

For a hydrocarbon reservoir, the following parameters are used in the general material balance equation (MBE). 
The total pore volume (in rb) of the reservoir is:
Consider the following diffusivity equation for the radial flow of a fluid in an infinite and homogeneous reservoir. \[ \frac{1}{r} \frac{\partial}{\partial r} \left( r \frac{\partial P}{\partial r} \right) = \frac{1}{\eta} \frac{\partial P}{\partial t} \] where, \( P \) denotes pressure, \( r \) is the radial distance from the center of the wellbore, \( t \) denotes time, and \( \eta \) is the diffusivity constant. The initial pressure of the reservoir is \( P_i \). The condition(s) used in the derivation of analytical solution of the above equation for pressure transient analysis in an infinite acting reservoir is/are:
Four different multilateral well patterns (Forked, Branched, Dual opening and Splayed) are shown in the figure. Which ONE of the following options correctly identifies the multilateral well patterns?

For a hydrocarbon reservoir, the following parameters are used in the general material balance equation (MBE). 
The total pore volume (in rb) of the reservoir is:
Consider the following diffusivity equation for the radial flow of a fluid in an infinite and homogeneous reservoir. \[ \frac{1}{r} \frac{\partial}{\partial r} \left( r \frac{\partial P}{\partial r} \right) = \frac{1}{\eta} \frac{\partial P}{\partial t} \] where, \( P \) denotes pressure, \( r \) is the radial distance from the center of the wellbore, \( t \) denotes time, and \( \eta \) is the diffusivity constant. The initial pressure of the reservoir is \( P_i \). The condition(s) used in the derivation of analytical solution of the above equation for pressure transient analysis in an infinite acting reservoir is/are: