PTA Quiz

The following self-assessment test is to help you decide which course is best suited to you; PTA/RTA Week 1 or PTA/RTA Week 2.

1. A correctly designed test should:
Three answers

Minimize test duration
Be long enough to reach radial flow
Have a duration exceeding the WBS effect
Always be long enough to reach any suspected boundaries
Include a multi-rate sequence

2. Before starting any analysis it is essential to:
Two answers

QAQC pressure gauge data
Obtain the formation permeability
Ensure the rate history and the pressure data are synchronized

3. The governing conditions for the diffusivity equation are:
Three answers

The fluid is highly compressible
The fluid is slightly compressible
The formation is isotropic and homogeneous
The PVT parameters are constant
The fluid is an hydrocarbon
The vertical permeability is equal to the horizontal permeability

4. The parameters influencing the permeability calculation are:
Two answers

The porosity
The net pay thickness
The PVT parameters
Well damage

5. In the Darcy’s Law equation Delta p = q.B.µ/A.k . The variables are:
Check the corresponding cell

	Viscosity	Pressure drop	Area of flow	Permeability	Rate	Volume factor
Delta p
q
B
µ
A
k

6. The skin factor can influenced by:
Three answers

The original formation permeability
Mud invasion
The perforations
The completion
The fluid

7. A back pressure test, or flow after-flow test, is:
Two answers

A multiple rate test
A test with equal duration production periods separated by shut in.
A test with a sequence of consecutive production periods

8. An isochronal test is:
Two answers

A multiple rate test
A test with equal duration production periods separated by shut in.
A test with a sequence of consecutive production periods

9. A modified isochronal test is:
One answer

Where the build-up period durations are equal to the production period durations
Where the build-up continues until the time of pressure stabilization

10. The objectives of a Well Test can be:
Four answers

To evaluate formation permeability
To evaluate well damage
To evaluate the hydrocarbon reserves
To evaluate the static reservoir pressure
To evaluate the formation porosity
To evaluate the oil saturation

11. The objectives of Gas Transient Test Analysis can be to evaluate:
Four answers

Formation permeability
The rate dependent skin
The AOF
Gas PVT parameters
Gas reserves
Gas saturation

12. Characteristics of constant wellbore storage effect include:
Two answers

P is a linear function of time
Unit slope straight line on the log-log plot
P is a linear function of log (time)

13. Wellbore Storage in a gas well is:
Four answers

Always constant
Dependent on the well volume upstream of the shut in valve
Dependent on well fluid compressibility
Dependent on the shut in well pressure
Dependent on the production rate
Reduced by using a downhole shut in tool

14. Based on the following skin values, what is your diagnosis?

Skin value	Fractured well	Acidized well	Damaged well
-5
+2
+10
-2

15. Which two are the most suitable diagnostic for analysis of a build-up after multiple rate flow periods?
Two answers

Semilog MDH plot
Cartesian plot
Horner plot
Superposition plot
Log-log pressure and derivative plot

16. What are the characteristics of Infinite Acting Radial Flow in a drawdown:
Two answers

The fluid flow lines in the formation are parallel
P is a linear function of log(delta T)
P is a linear function of log(tp+ delta t / delta t)
A horizontal line on the log-log derivative

17. What is the characteristic of Infinite Acting Radial Flow in a build-up:
One answer

P is a linear function of log(time)
P is a linear function of log(tp+ delta t / delta t)
We see a unit slope straight line on the log-log derivative

18. What are the characteristics of linear flow
Two answers

P is a linear function of time
P is a linear function of the square root of the time
A ½ unit straight line on the log-log derivative

19. A Horner analysis is strictly valid
One answer

During the first drawdown period
On the first build-up after a drawdown period
At the build-up after any number of rates

20. From the Horner plot straight line drawn through IARF it is possible to extract the:
Three answers

kh
S
P*
C

21. What is the effect of a single sealing fault:
Two answers

A unit slope straight line on the log-log derivative
The semilog straight line slope doubles
The log derivative stabilizes at twice the IARF stabilization
The derivative curves down

22. The AOF is the:
One answer

Minimum gas rate of the tested well
Extent of the drainage area
Maximum theoretical gas rate with Pwf = Patm
Gas well productivity index

23. In a fractured well which of the following flow regimes can be observed?
Four answers

Linear flow
WBS effect
Bilinear flow
Spherical flow
IARF

24. In a horizontal well the first derivative stabilization corresponds to:
One answer

Linear flow
Wellbore storage
Pseudo-radial flow around the horizontal drain

25. On the following log-log plot identify the lines:

Line one	WBS	IARF	Sealing fault	Pseudo-steady state
Line two	WBS	IARF	Sealing fault	Pseudo-steady state
Line three	WBS	IARF	Sealing fault	Pseudo-steady state