Reducing grid-block size in a finite-difference reservoir model generally:
A) Always increases numerical dispersion
B) Improves spatial resolution but increases computational cost
C) Eliminates all numerical errors
D) Makes timestep selection irrelevant
💬 Comment your answer: A/B/C/D

For a volumetric undersaturated oil reservoir above bubble point, with negligible water influx and no gas cap, the dominant drive mechanism is:
A) Gas-cap expansion
B) Water influx
C) Rock and fluid expansion
D) Gravity segregation
💬 Comment your answer: A/B/C/D

In drilling engineering, what is the critical annular velocity parameter required to ensure effective hole cleaning in deviated wells?


A.
Lower annular velocity to prevent formation fracturing

B.
Using Newtonian fluids exclusively

C.
Higher cutting transport velocity relative to vertical holes

D.
Eliminating mud rotation entirely

Which relative permeability characteristic defines a strongly water-wet rock system?


A.
Imbibition capillary pressure is predominantly negative

B.
Water relative permeability is low at high water saturations

C.
The crossover point of relative permeability curves occurs at a water saturation greater than 0.5

D.
Residual oil saturation approaches zero instantly

In well log interpretation, how does the presence of shale affect the apparent porosity calculated from a density-neutron crossplot?


A.
Shale has no impact on radiation or scattering logs

B.
Shale typically shifts neutron porosity higher and density porosity higher due to lower matrix density and bound water

C.
Shale causes a separation known as the shale 'gas' or crossover effect incorrectly

D.
Shale increases apparent neutron porosity and decreases apparent density porosity

What is the primary function of a packer in a production well completion string?


A.
To measure continuous downhole multi-phase flow rates

B.
To increase bottomhole reservoir pressure artificially

C.
To isolate the annulus from the production tubing and protect the casing from high pressures and corrosive fluids

D.
To filter out sand grains entering the wellbore

Which enhanced oil recovery (EOR) method primarily relies on lowering interfacial tension (IFT) to near-zero values to mobilize trapped residual oil?


A.
Cyclic steam stimulation

B.
Waterflooding

C.
In-situ combustion

D.
Surfactant flooding

When designing hydraulic fracturing treatments, what parameter dictates the width of the created hydraulic fracture under plane-strain assumptions?


A.
Proppant density and specific gravity exclusively

B.
Fluid filtration rate alone independent of rock mechanics

C.
Drill string rotation speed and mud weight window

D.
Net pressure (p−σ
h
​
) and formation elastic properties (Young's modulus E, Poisson's ratio ν)

You open a gas well's choke wider and the wellhead temperature rises. Why?
A) Joule-Thomson heating at the choke
B) Higher rate carries more reservoir heat up the tubing
C) Gas composition changes
D) Pressure increases upstream

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In gas reservoir engineering, what is the purpose of utilizing real gas pseudopressure (m(p)) instead of standard pressure (p) when analyzing gas well test data?


A.
To account for the pressure dependency of gas viscosity and gas compressibility factor (z)

B.
To simplify calculations assuming ideal gas behavior at high pressures

C.
To eliminate the need for skin factor corrections

D.
To convert dry gas metrics directly into black oil volumetric equivalents

Why is the pore pressure and fracture gradient window narrow in deepwater?
A) Seawater has high density
B) Formations are always overpressured
C) Seawater replaces rock in the overburden, lowering fracture gradient
D) Mud weight is always too low

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Core porosity is 20% but density log reads 28%. A valid non-tool-failure reason is:
A) Wrong matrix density assumed in the log
B) Core is always more accurate
C) Log measures permeability
D) Mud filtrate has no effect

A well flows naturally, yet the operator adds gas lift. The most likely reason is:
A) To increase reservoir pressure
B) To raise oil viscosity
C) To lighten the fluid column and increase drawdown and rate
D) To reduce GOR