Category: Engineering Geology Objective Questions

Engineering Geology Multiple Choice Questions on “Parts of a Fold”.

1. What are the undulations or bends developed in rocks called?
a) Faults
b) Joints
c) Folds
d) Uncomformity
Answer: c
Clarification: Folds may be defined as undulations or bends or curvatures developed in the rocks of the crust as a result of stresses to which these rocks have been subjected from time to time in the past history of the Earth.

2. Folds develop in which type of rock?
a) Igneous rock
b) Sedimentary rock
c) Metamorphic rock
d) Any type of rock
Answer: d
Clarification: The folds may develop in any type of rock and may be of any shape and flexures.

3. Which type of deformation is folding?
a) Brittle
b) Ductile
c) Tensile
d) Malleable
Answer: b
Clarification: In general, folding is a ductile type of deformation experienced by the rocks compared to the brittle deformation where the rocks actually get broken and displaced when stressed.

4. Folding is ________ process.
a) Very slow
b) Rapid
c) Quick
d) Moderate rate
Answer: a
Clarification: Folding is a very slow geological process and indicates an effort of the rocks in a particular environment to adjust themselves to the changing force fields operating on, within or around them.

5. Which among the following is not a part of fold?
a) Limbs
b) Hinge
c) Axis of fold
d) Height of fold
Answer: d
Clarification: Parts of a fold include, limbs, hinge, axis of a fold, plunge of a fold and crest & trough. Height of fold is not referred as its part.

6. The minimum number of limbs for a fold are _____________
a) 1
b) 2
c) 3
d) 4
Answer: b
Clarification: An individual fold will have a minimum of two limbs but when the folds occur in groups, as this is common, a middle limb will be common to two adjacent folds.

7. The point where the curvature is maximum is ________
a) Hinge
b) Axial surface
c) Nucleus
d) Fold point
Answer: a
Clarification: In a folded layer, a point can be found where curvature is maximum and one limb ends and the other limb starts from that point. This is the hinge point.

8. When the plunge said to be zero, then the axis of the fold is said to be ____________
a) Vertical
b) Horizontal
c) Inclined at 60° to the horizontal
d) Inclined at 60° to its normal.
Answer: b
Clarification: Axis is a line and plunge is the angle which the line makes with a horizontal. A fold having a horizontal axis will obviously have a zero plunge.

9. The crest and trough may or may not coincide with the axis.
a) True
b) False
Answer: a
Clarification: The line running through the highest points in an uparched fold defines the crest and similarly the line running through the lowest point in a downarched fold makes its trough. The crest and trough may or may not coincide with the axis of the fold.

10. What is the axis of a fold?
a) Line drawn normal to the hinge line
b) Line drawn at 60° to hinge line
c) Line drawn parallel to hinge line
d) Line which doesn’t pass through hinge line.
Answer: c
Clarification: Axis of fold is defined as a line drawn parallel to the hinge line of a fold. In other words, line representing the intersection of the axial plane of a fold with any bed of the fold.

11. How is the plunge of a fold measured?
a) Direction
b) Degree
c) Depth
d) Both direction and degree
Answer: d
Clarification: The plunge is measured like a dip of a bedding plane, both in terms of the direction of plunge and degree of plunge.

12. An axial plane can be vertical, inclined or horizontal in nature.
a) False
b) True
Answer: b
Clarification: An axial plane is that imaginary plane that passes through all the points of maximum curvature in a folded sequence. It may be vertical, inclined or horizontal in nature.

13. Identify the part labelled “A” in the below figure.

a) Limb
b) Hinge
c) Axis of fold
d) Plunge
Answer: a
Clarification: Limbs are the sides or flanks of a fold. The part labelled “A” in the figure is a limb of fold.

14. Which of the following about axial plane is not true.
a) Axial plane is imaginary
b) Axial plane may be vertical, inclined or horizontal
c) Axial plane may be planar or non-planar
d) Axial plane need not pass through all points of maximum curvature in a folded sequence
Answer: d
Clarification: An axial plane is defined as an imaginary plane that passes through all the points of maximum curvature in a folded sequence. It may be vertical, inclined or horizontal. Also, it can be either planar or non-planar.

Engineering Geology Multiple Choice Questions on “Engineering Considerations of Faults”.

1. What kind of joints do the faulted rocks form?
a) Strong
b) Weak
c) Doesn’t change
d) Extended
Answer: b
Clarification: The faulted rocks will form weak foundations and abutments for dam, despite the fact that originally they might have been strong and impervious.

2. When do the faulted and shear zones become potential areas of further slip and slides?
a) Dry
b) Lubricated
c) Weathered
d) Heavy winds
Answer: b
Clarification: Once the fault zones, shear zones or fault surfaces become lubricated with water, they become potential areas for further slips and slides. They may create critical conditions.

3. Where should a site for a civil engineering project be located?
a) On faulted zone
b) On a folded strata
c) On a joint
d) Must be avoided to possible extent to be built on all three
Answer: d
Clarification: As far as possible the location of a civil engineering project must be avoided on a fault or a fold or a joint. But when there is no other choice, the same location can be treated with necessary methods and then the project can be implemented.

4. What is not considered about the shear zones?
a) Number
b) Size
c) Inclination
d) Appearance
Answer: d
Clarification: The number, size and inclination of the shear zones should be given top consideration.

5. Bhakra dam in India showed which occurrence?
a) Fault zones
b) Slickensides
c) Shear zones
d) Folds
Answer: c
Clarification: The embankment of the Bhakra dam in India showed occurrence of numerous shear zones in them; the site could not be changed because of other reasons; hence it was decided to treat the shear zones by extensive excavations of the shear zones and back filling with cement grouting.

6. What are faults associated with?
a) Volcanic activity
b) Precipitation
c) Earthquake
d) Folds
Answer: c
Clarification: Faults of any significance are always associated with earthquakes. The tectonic history of the area under consideration must be known thoroughly.

7. What is recommended to be introduced to the structures even on safe land?
a) Proper dimensioning
b) Proper planning
c) Use high quality materials
d) Factor safety
Answer: d
Clarification: Some factor of safety has to be introduced in the building even though the tectonic history indicates not movement of the surface or plate. It is always recommended to introduce factor of safety for high raised buildings or even buildings which are built on active seismic zones.

8. Studying tectonic history is basically like knowing ___________
a) Frequency of earthquake
b) Effects
c) Frequency, effects and magnitude
d) Cost for recuperation
Answer: a
Clarification: Study of tectonic history would virtually mean obtaining information about the frequency of the earthquakes as also their magnitude and effects that they have left from time to time on the rocks of the region.

9. Gouge and breccia don’t create any problems during construction.
a) True
b) False
Answer: b
Clarification: Faulting products like gouge and breccia create additional problems; the site has to be cleared of them or taken below to the sound bedrock.

Engineering Geology Multiple Choice Questions on “Important Metamorphic Rocks – 01”.

1. Slate is originated from which rock?
a) Sandstone
b) Granite
c) Shale
d) Basalt
Answer: c
Clarification: Slate is a product of low-grade regional metamorphism of argillaceous rocks like clays and shales.

2. Low grade schist is formed under what conditions?
a) Low temperature and local metamorphism
b) High temperature and local metamorphism
c) Low temperature and regional metamorphism
d) Low temperature and regional metamorphism
Answer: c
Clarification: Low grade schists are formed under conditions of regional metamorphism at low temperature. These are rich in minerals like albite, muscovite and chlorite that are unstable at high temperature.

3. What is the grain size of slate rock?
a) Fine
b) Medium
c) Coarse
d) Very coarse
Answer: a
Clarification: Slate is an extremely fine-grained metamorphic rock characterized by a slaty cleavage by virtue of which it can be readily split into thin sheets having parallel smooth surfaces.

4. High grade schist is formed under what conditions?
a) Local metamorphism
b) Regional metamorphism
c) Displacement metamorphism
d) Chain metamorphism
Answer: b
Clarification: High grade schists are formed under conditions of regional metamorphism and atoms rich in minerals that are stable at high temperatures such as garnet.

5. Examples of high grade schist is ___________
a) Talc- schist
b) Garnet-schist
c) Chlorite-schist
d) Mica-schist
Answer: b
Clarification: Garnet-schists, cordierite-schists and staurolite-schists are common examples of some high grade schists.

6. Special property of talc schist is __________
a) Colour
b) Its structure
c) Soapy feel
d) Good odour
Answer: c
Clarification: Talc schist is a low grade schist and its special property is that it gives a soapy feel when touched with bare hands.

7. Gneiss formed from sedimentary rock is called __________
a) Orthogneiss
b) Paragneiss
c) Banded gneiss
d) Augen gneiss
Answer: b
Clarification: Paragneiss are formed from the metamorphism of sedimentary rocks like sandstone. Orthogneiss formed as a result of metamorphism of granites and other igneous rocks.

8. The similar type of rock to quartzite which is sedimentary is __________
a) Compound quartzite
b) Orthoquartzite
c) Holo-quartzite
d) Accu-quartzite
Answer: b
Clarification: The name orthoquartzite is used for a sedimentary rock of similar composition but having different origin, in which quartz grains are cemented together by siliceous cement.

Engineering Geology Multiple Choice Questions on “Causes of Mass Movements –
01”.

1. The factors that cause the failure are generally grouped into how many?
a) 1
b) 2
c) 3
d) 4
Answer: b
Clarification: All the factors that facilitate mass failure in one way or another are generally grouped in two headings: Internal factors and External factors.

2. The causes which tend to reduce the shearing strength of the soil are __________
a) Internal factors
b) External factors
c) Extensive factors
d) Weather factors
Answer: a
Clarification: Internal factors include such cases, which tend to reduce the shearing strength of the soil or rock mass by virtue of which it had remained stable at a given position on the ground.

3. Nature of slope includes __________
a) Type of material and angle of mass
b) Mass of material and type of material
c) Type of material and shape of mass
d) Mass of material and angle of mass
Answer: a
Clarification: The nature of slope includes two important characters of the slope. By nature of slope is meant here the type of material of which the land mass is made up and the angle at which this particular mass is inclined with the horizontal.

4. The force which helps to retain the position of mass in space is __________
a) Compressive resistance
b) Tensile resistance
c) Shearing resistance
d) Bending resistance
Answer: c
Clarification: The most important force among the forces by virtue of which it can retain its position in space is undoubtedly the shearing resistance of the mass.

5. The force which tends to induce failure is __________
a) Shearing resistance
b) Force due to gravity
c) Force due to compression
d) Force due to loading
Answer: b
Clarification: Among the forces that tend to induce failure in a mass, the most important is the pull due to gravity which acts through the weight of the material.

6. When the forces tending to induce failure dominate over those tending to resist failure, the mass becomes stable.
a) True
b) False
Answer: b
Clarification: As, when and where the forces tending to induce failure dominate over those tending to resist failure, the mass becomes unstable.

7. The angle of slope up to which the materials are stable in a slope is called __________
a) Shear angle
b) Angle of failure
c) Critical angle
d) Sub-angle
Answer: c
Clarification: It has been observed that most materials are stable up to a certain angle of slope. This is called the critical angle of slope or also called as angle of repose and varies from 35° for unconsolidated sediments to 90° for perfectly crystalline unjointed rocks.

8. In the recent times what other aspect of the slope is considered for its stability?
a) The type of rocks in the slope
b) The type of land mass below the slope
c) Height of the slope
d) Length of the slope
Answer: c
Clarification: In fact much importance has been attached in recent times to the height of the slope in addition to the angle of slope for determining the factor of safety.

9. Solvent action can been seen in rocks which are made of _______ minerals.
a) Active
b) Inactive
c) Soluble
d) Insoluble
Answer: c
Clarification: The solvent action of water should also not be underestimated. In rocks like gypsum and limestone, or in those rocks which have soluble minerals as their constituents, water may gradually remove the soluble components reducing the shearing strength of the mass.

Tough Engineering Geology Questions and Answers on “Works of Streams and Rivers – 02”.

1. The variously shaped depressions of different dimensions that are developed in the riverbed are called __________
a) Potholes
b) Cavities
c) Dents
d) Craters
Answer: a
Clarification: Potholes are variously shaped depressions of different dimensions that are developed in the riverbed by excessive localized erosion by the streams.

2. Every major river is associated with a valley of its own.
a) True
b) False
Answer: a
Clarification: A valley may be defined as a low land surrounded on sides by inclined hill slopes and mountains. Every major river is associated with a valley of its own.

3. Magnificent jumps made by a stream or river water at certain specific parts of their course where there is a sudden and considerable drop in the gradient of the channel are called __________
a) Streams
b) Hydraulic jumps
c) Waterfalls
d) Knick-jumps
Answer: c
Clarification: Waterfalls are magnificent jumps made by a stream or river water at certain specific parts of their course where there is a sudden and considerable drop in the gradient of the channel.

4. The most common type of flood plains are __________
a) Flat flood plains
b) Simple flood plains
c) Compound flood plains
d) Complex flood plains
Answer: d
Clarification: Convex flood plains are the most common type and are associated with many major rivers of the world.

5. Alluvial deposits of roughly triangular shape that are deposited by major rivers at their mouths are called __________
a) Deltas
b) Backwaters
c) Lakes
d) Streams
Answer: a
Clarification: Deltas are defined as alluvial deposits of roughly triangular shape that are deposited by major rivers at their mouths, i.e., where they enter a sea.

6. A typical delta is made of how many layers?
a) 2
b) 3
c) 5
d) 4
Answer: b
Clarification: A typical simple delta is commonly made of three layers of which only the top layer may be sub aerial, that is exposed on the surface.

7. The fore-set beds are intermediate layers.
a) True
b) False
Answer: a
Clarification: The fore-sets are the intermediate layers and often show very steep inclination. The fore-set beds are made up of thick layers of sand and clay.

8. The condition not favouring the formation of delta is __________
a) Absence of strong sea currents
b) Presence of good quality of load
c) Slope of seashore where the stream enters must be gentle
d) Presence of strong sea currents
Answer: d
Clarification: Three conditions necessary for the formation and growth of a delta are: absence of any strong sea currents; presence of good quality of load in the stream and the slope of seashore where the stream enters the seawater must necessarily be quite gentle and wide.

9. Places of steep drops in elevation in the course of a river are called __________
a) Depressions
b) Cavities
c) Knickpoints
d) Nickopoints
Answer: c
Clarification: Kickpoints are actually places of steep drops in elevation in the course of a river. These are very often caused due to presence of rocks of unequal hardness at those places.

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