Geophysics 559-University of Calgary

Geophysics 559-Geophysical Interpretation

In class midterm will be mostly multiple choice; but there will be also written questions.

Disclaimer: While every reasonable effort is made to ensure that the information provided is accurate, no guarantees for the currency or accuracy of information are made. It takes several proof readings and rewrites to bring the quiz to an exceptional level. If you find an error, please contact me as soon as possible. Please indicate the question ID-Number or description because server may randomize the questions and answers.

Geophysics 559 (GOPH 559) Midterm

Please wait while the activity loads.
If this activity does not load, try refreshing your browser. Also, this page requires javascript. Please visit using a browser with javascript enabled.

If loading fails, click here to try again

Some questions have hints and explanations. Click Start to begin.

Start

Congratulations - you have completed Geophysics 559 (GOPH 559) Midterm.

You scored %%SCORE%% out of %%TOTAL%%. With incorrect multiple tries your score is %%PERCENTAGE%%

Your performance has been rated as %%RATING%%

Your answers are highlighted below.

Question 1

Measurements made in a mountainous terrain would give ___ gravity readings. (ID-GIM-06)

A	Not enough information to answer the question.
B	high
C	low

Question 2

You are a fracking expert. In which direction would you expect to have the highest permeability in a fracked region? (ID-GIM-13)

A	Along any angle between the fractures and natural permeability pathways.
B	Across or perpendicular to fractures.
C	Along the plane of the fractures.
D	It depends on the rock type and the formation.

Question 2 Explanation:

The whole point of fracking is to increase the permeability which occurs along the fractures.

Question 3

What is the best probable seismic velocity for tight limestone? (ID-GIM-03)

A	4000 m/s
B	1500 m/s
C	6000 m/s
D	10 m/s
E	200 m/s

Question 3 Explanation:

You should have a general idea about what velocities to expect from each layer!

Question 4

The normal moveout deal with the... (ID-GIM-24)

A	reduction of seismic resolution as a result of smaller variation in densities of different layers and the depth to the reflection surface.
B	resolution of layers with extremely small difference in densities.
C	effect that the distance between a seismic source and a receiver (the offset) has on the arrival time of a reflection.
D	density contrast between two layers adjacent to each other.

Question 5

Which of the following is situated at the highest temperature / depth? (ID-GIM-17)

A	Oil window
B	Oil floor
C	Wet gas preservation limit
D	Dry gas preservation limit

Question 6

Which of the following best describe a real world scenario? (ID-GIM-02)

A	A very good reservoir with no significant traps.
B	Gas at the very top of the reservoir followed by oil and water as the depth increases.
C	Oil at the very top of the reservoir followed by gas and water as the depth increases.
D	A very good reservoir with 100% pure oil and no impurities or other type of fluids.

Question 7

What is the primary factor driving the hydrocarbon migration from structurally low to structurally high regions? (ID-GIM-11)

A	Pressure
B	Gravity
C	Temperature
D	Porosity
E	Buoyancy

Question 8

What is the best temperature range for petroleum source rocks? (ID-GIM-09)

A	200 - 350 degree Celsius
B	20 - 200 degree Celsius
C	0 - 200 degree Celsius
D	50 - 150 degree Celsius
E	250 - 350 degree Celsius

Question 9

Which of the following is the best description for a hydrocarbon trap? (ID-GIM-08)

A	A Geologic area that is capable of containing hydrocarbons due to relatively impermeable barrier.
B	A highly conductive (high effective porosity) stratigraphic or a rock body that is capable of containing hydrocarbon.
C	A specific area of a specific Formation in which the temperature is between 50 - 150 degree Celsius.
D	A body of rock that is capable of containing hydrocarbons due to perfectly impermeable barrier.

Question 9 Explanation:

You may have found more than one answer possible for this question. You are WRONG; please study harder. 😉

Question 10

Given the gravitational attraction of a Bouguer slab (a layer) by 2πGρt, where G is the universal gravitational constant, ρ is the slab density and t is the thickness. The gravity meter that pass from top to the bottom layer will result in what type of reading? (ID-GIM-23)

A	It will be a increased reading by a factor of 2πGρt.
B	It will be a increased reading by a factor of 4πGρt.
C	It will be a reduced reading by a factor of 4πGρt.
D	It will be a reduced reading by a factor of 2πGρt.

Question 11

Electrical and electromagnetic surveys are typical used for measuring what type of physical properties? (ID-GIM-21)

A	Identification of basement features
B	Oil and gas exploration
C	Mineral exploration
D	Hydrological research (drinking water, fresh water)

Question 12

Given a sampling interval of 3ms, calculate it's Nyquest frequency. (ID-GIM-30)

A	322.9 Hz
B	255.8 hz
C	166.7 Hz
D	512.2 Hz

Question 12 Explanation:

F_N = 1/2t

Question 13

In reflection seismology, the velocity is estimated using what technique? (ID-GIM-28)

A	Reciprocity
B	Normal Moveout
C	Deconvolution
D	Convolution

Question 14

The peak oil generation occurs at what temperature? (ID-GIM-10)

A	200 degree Celsius
B	90 degree Celsius
C	70 degree Celsius
D	150 degree Celsius
E	50 degree Celsius

Question 15

You randomly weighed an item in several different locations on Earth, at which location would you expect the record the highest weight reading? (ID-GIM-19)

A	The location with the highest elevation and the lowest latitude.
B	The location with the lowest elevation and the highest latitude.
C	The location between the equator and the poles (middle).
D	The location closest to the poles.
E	The location closest to the equator.

Question 16

Which of the following is a stratigraphic trap? (ID-GIM-14)

A	Folds
B	Foliations
C	Reefs
D	Faults

Question 17

Rays travel in paths that would take the least amount of time. This law/principle is known as... (ID-GIM-22)

A	Snell's Law
B	Principle of Reciprocity
C	Refraction Law
D	Fermat's Principle

Question 18

What does a seismic geophone detect or measure? (ID-GIM-01)

A	Vibrations
B	Density of formations
C	Speed or velocity
D	Depth of reflectors

Question 19

In seismic signal processing, coherency can be best described as a function of... (ID-GIM-31)

A	...frequency (and frequency only).
B	...wavelength (and wavelength only).
C	...similarities between seismic events.
D	...time (and time only).

Question 20

Areal survey is a relatively cheap method of seismic data acquisition. This type of surveys have been used for over, (ID-GIM-25)

A	150 years.
B	20 years.
C	50 years.
D	100 years.

Question 21

Poisson's relation is between what type of energy, forces or concepts? (ID-GIM-07)

A	Gravitational and Potential energy
B	Gravitational and Magnetic forces
C	Incident and Refractory rays
D	Spring Constant and magnitude of gravity

Question 22

Which of the following will result in aliasing? (ID-GIM-29)

A	Decrease in period.
B	Having a frequency below the Nyquist value.
C	Increase in seismic frequency.
D	Increasing spatial sampling.

Question 23

Which of the following statement is true? (ID-GIM-27)

A	The head wave only travels in the first medium.
B	The direct wave travels faster than the head wave.
C	The head wave travels further than the direct wave, but it has a higher velocity.
D	The direct wave has a sinusoidal wave form while the head wave does not.

Question 24

What is the zero length spring? (ID-GIM-20)

A	A spring that is under maximum tension (maximum stretch).
B	A theoretical name given to springs that are not being stretch.
C	A theoretical name given to springs that obey its spring constant, k.
D	A theoretical name given to springs that do not obey its spring constant, k.
E	A spring that has no length but only diameter.

Question 25

What is an another tern used to describe a head wave in reflection seismology? (ID-GIM-26)

A	Transmitted wave
B	Critically refracted arrival
C	Direct wave
D	Refracted arrival
E	Guided wave

Question 26

If a bottom of a reservoir containing oil, water and gas begins to leak due to permeability increase in the bottom sea, what fluid would most likely to drain first? (ID-GIM-18)

A	Oil
B	Cannot be answered with the given information.
C	Gas
D	Water

Question 26 Explanation:

This is a practical question. Since all three fluid types are present, the densities dictate which fluid will be stable as depth increase. Hence, gas-oil-water from top to bottom. If the bottom seal leaks, the first fluid to escape is water.

Question 27

Which of the following seismic method is most sensitive to variation in physical properties of lithology? (ID-GIM-32)

A	Seismic interference
B	Magnetic survey
C	Acoustic impedance
D	None of the above
E	Gravity survey

Question 28

Which of the following will result in a high gravity reading? (ID-GIM-05)

A	Free Air and Terrain effects
B	Free Air and Slab effects
C	Latitude and Free Air effects
D	Latitude and Slab effects
E	Slab and Terrain effects

Question 29

Which of the following is the best method to interpret the processes of source-rock deposition? (ID-GIM-15)

A	Density measurements obtained through seismic data.
B	2D and 3D structural modeling of the area.
C	Advanced well-logging data obtained through a combination of core samples and seismic data.
D	Comprehensive understanding of the regional Geology.

Question 29 Explanation:

You may found that more than one answer is possible. You are WRONG; only one answer is correct.

Question 30

Which of the following type of rock/lithology has the highest density? (ID-GIM-16)

A	Sandstone
B	Shale
C	Limestone
D	Igneous rocks
E	Salt

Question 31

A tight reservoir would have a permeability of ___ millidarcys (md). (ID-GIM-12)

A	greater than 10
B	less than 40
C	greater than 30
D	less than 5
E	greater than 50

Question 32

You obtained a seismic profile and core samples for an area of interest. The core samples indicate that the lithology in the area is the same. However, the seismic profile shows lower velocities in some localized regions. What is most likely the cause for this anomaly? (ID-GIM-04)

A	Change in dip angles.
B	Change in density.
C	Change in lithology.
D	Fractures within the formation.

Question 32 Explanation:

Change in density is also a possible answer. But the best answer is fractures within the formation. If there is a large density change then the lithology must have been changed too. However, the core samples shows that the lithology is the same.

Once you are finished, click the button below. Any items you have not completed will be marked incorrect. Get Results

There are 32 questions to complete.

←

List

→

Return

Shaded items are complete.

1	2	3	4	5
6	7	8	9	10
11	12	13	14	15
16	17	18	19	20
21	22	23	24	25
26	27	28	29	30
31	32	End

Return

Credits: Based on the excellent class notes provided by, Dr. Laurence Lines during Winter 2015.
FAQ | Report an Error

If you get a question wrong, you can still click on the other answers. This will open up hints and explanations (if available), which will provide additional information.

Given the faulted slab equation, , prove that the edge of the buried slab occurs at the inflection point of the gravitational profile curve.

Sanuja Senanayake

Geophysics 559-University of Calgary

Geophysics 559 (GOPH 559) Midterm

Standing on the shoulders of giants

Geophysics 559 (GOPH 559) Midterm

Print/Share:

Standing on the shoulders of giants