An ESP produces significantly less head than expected despite correct rotational speed. The most likely cause is:
A) Free gas interference at pump intake
B) Increased reservoir permeability
C) Reduced water cut
D) Higher oil API gravity
💬 Comment your answer: A/B/C/D

A sandstone well has low productivity because of near-wellbore formation damage caused by fines. The most appropriate approach is generally:
A) Hydraulic fracturing only
B) Acid treatment appropriate to the damage mechanism
C) Gas lift
D) Water injection
💬 Comment your answer: A/B/C/D

A positive skin factor � indicates:
A) Formation stimulation
B) Near-wellbore damage
C) Infinite permeability
D) Zero pressure drop
💬 Comment your answer: A/B/C/D

For immiscible water flooding, increasing the viscosity of injected water while keeping oil properties unchanged generally:
A) Increases mobility ratio
B) Decreases mobility ratio
C) Has no effect
D) Makes relative permeability equal to 1
💬 Comment your answer: A/B/C/D

During circulation, bottom-hole pressure is greater than static hydrostatic pressure primarily because of:
A) Formation temperature
B) Annular frictional pressure loss
C) Drillstring weight
D) Bit rotation
💬 Comment your answer: A/B/C/D

For gas material-balance calculations, which quantity is commonly used to account for gas compressibility?
A) p
B) p/z
C) z
D) zp
💬 Comment your answer: A/B/C/D

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