Engineering Geology Multiple Choice Questions on “Fault Terminology – 01”.
1. What are the fractures along which there has been relative movement of blocks called?
a) Folds
b) Joints
c) Faults
d) Intrusions
Answer: c
Clarification: The definition of faults is “Those fractures along which there has been relative movement of the blocks past each other”. The entire process of development of fractures and displacement of the blocks against each other is termed as faulting.
2. What is the key word in the definition of fault?
a) Fracture
b) Movement
c) Both fracture and movement
d) Dip
Answer: c
Clarification: The key words in the definition are fracture and movement. The exact significance of these key words must be clearly understood.
3. For a rock structure to be called fault, fracture has to happen but movement is not necessary.
a) True
b) False
Answer: b
Clarification: There can be no fault if there is no fracture surface or zone and also evidence of some relative movement of the blocks against each other is a must for qualifying that fracture as a fault.
4. Faulting is a _________ process.
a) Tectonic
b) Non-tectonic
c) Both tectonic and non-tectonic
d) Precipitation
Answer: a
Clarification: Faulting is a major tectonic process of great geological importance. The geological history of the Earth bears innumerable events recording in the script of folding, faulting and jointing.
5. In which direction does the displacement of blocks happen?
a) Horizontal
b) Vertical
c) Inclined
d) Any direction
Answer: d
Clarification: The displacement of blocks created in the rock due to faulting may take place in any direction: parallel to the fault surface; in an inclined manner or even rotational.
6. What is the angle that can be made by fault plane with the horizontal?
a) Acute angle only
b) Obtuse angle only
c) Right angle
d) Any angle
Answer: d
Clarification: Fault planes may be vertical, horizontal or inclined at any angle with the horizontal.
7. What is the planar surface of fracture along which relative displacement of bodies has taken place called?
a) Fault plane
b) Fold plane
c) Stress plane
d) Strain plane
Answer: a
Clarification: Fault plane is the planar surface of fracture along which relative displacement of the blocks takes place during the process of faulting. When it is not planar, the same surface is simply described as fault surface.
8. What is the angle of fault plane with the horizontal called?
a) Hade
b) Strike
c) Dip
d) Inclination
Answer: c
Clarification: The dip of the fault is its inclination with the horizontal as measured in a vertical plane at right angles to the strike of the fault.
9. Parameter(s) considered for dip is ___________
a) Direction
b) Angle
c) Direction and angle
d) Neither direction nor angle
Answer: c
Clarification: The dip is measured both in terms of the direction of dip as well as angle of dip just as in the bedding plane of strata.
10. What is hade?
a) Inclination of fault with horizontal
b) Inclination of fault with vertical
c) Inclination of fault with any strata
d) Bearing of the fault with ground
Answer: b
Clarification: The hade of the fault is the angle which the fault makes with the vertical. In other words, it is the complimentary to the dip angle.
11. What is the bearing of a line of intersection of fault plane and horizontal called?
a) Strike
b) Dip
c) Hade
d) Intersection line
Answer: b
Clarification: The strike of the fault is the bearing or geographical direction of a line obtained by the intersection of a horizontal plane with the fault plane.