Match the well logging methods in GROUP I with their corresponding measured parameters in GROUP II.
\begin{tabular}{|c|c|}
\hline
GROUP I & GROUP II
\hline
(P) Neutron log & (I) Resistivity in the flushed/invaded zone
(Q) Density log & (II) Hydrogen ion concentration in the formation
(R) Microspherically Focused Log (MSFL) & (III) Interval transit time of a compressional wave
(S) Sonic log & (IV) Electron density of the formation
\hline
\end{tabular}
\hline (P) Neutron log & (I) Resistivity in the flushed/invaded zone
(Q) Density log & (II) Hydrogen ion concentration in the formation
(R) Microspherically Focused Log (MSFL) & (III) Interval transit time of a compressional wave
(S) Sonic log & (IV) Electron density of the formation
\hline \end{tabular}
Show Hint
- P – IV; Q – I; R – II; S – III
- P – II; Q – IV; R – I; S – III
- P – II; Q – III; R – IV; S – I
- P – III; Q – IV; R – I; S – II
The Correct Option is B
Solution and Explanation
Neutron logs measure hydrogen concentration (actually hydrogen index), which correlates with porosity because hydrogen is primarily present in formation fluids. \[ \Rightarrow \text{Neutron log → (II) Hydrogen ion concentration}. \] Step 2: Density log.
Density logs measure the bulk density of formation by gamma-ray scattering. This is directly related to electron density. \[ \Rightarrow \text{Density log → (IV) Electron density}. \] Step 3: Microspherically Focused Log (MSFL).
MSFL measures shallow resistivity in the flushed/invaded zone (near-wellbore zone after mud invasion). \[ \Rightarrow \text{MSFL → (I) Resistivity in the flushed zone}. \] Step 4: Sonic log.
Sonic logs measure the travel time of compressional waves (Δt) across the formation. \[ \Rightarrow \text{Sonic log → (III) Interval transit time}. \] Final Mapping:
P – II, Q – IV, R – I, S – III Final Answer: \[ \boxed{\text{(B)}} \]
Top Questions on Reservoir and channel routing
For a hydrocarbon reservoir, the following parameters are used in the general material balance equation (MBE):
\[ \begin{aligned} N & = \text{Initial (original) oil in place, stb} \\ G & = \text{Initial volume of gas cap, scf} \\ m & = \text{Ratio of initial volume of gas cap to volume of oil initial in place, rb/rb} \\ S_{wi} & = \text{Initial water saturation} \\ S_{oi} & = \text{Initial oil saturation} \\ B_{oi} & = \text{Initial oil formation volume factor, rb/stb} \\ B_{gi} & = \text{Initial gas formation volume factor, rb/scf} \end{aligned} \]
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