Category: Engineering Geology Objective Questions

Engineering Geology Multiple Choice Questions on “Fault Terminology – 03”.

1. Heave is _______
a) Horizontal component of dip separation
b) Vertical component of dip separation
c) Normal horizontal displacement measured
d) Signifying separation between two beds
Answer: a
Clarification: Heave is the horizontal component of dip separation measured in a direction perpendicular to the strike of the fault in a vertical plane.

2. What signifies the actual separation between two beds?
a) Throw
b) Offset
c) Heave
d) Stratigraphic throw
Answer: d
Clarification: Stratigraphic throw signifies actual separation between two beds with a known stratigraphical position in a sequence of rocks that are now brought into contact by faulting.

3. What is the term related to slickensides and used to express the angular relationship?
a) Rake
b) Tweak
c) Slick
d) Offset
Answer: a
Clarification: Rake is a term related to slickensides in faults. It is used to express the angular relationship of slickensides or some other line with the fault plane.

4. Pick the term which is not a crushed material.
a) Gouge
b) Fault breccia
c) Kaolynite
d) Mylonite
Answer: c
Clarification: Rubbing and mutual shearing of blocks during faulting, especially in brittle rocks, often produces typical crushed materials from the involved blocks that are useful indicators of faulting in that region. The most common and important products are: Gouge, Fault breccia and Mylonite.

5. What is also called as Micro breccia?
a) Gouge
b) Mylonite
c) Kaolynite
d) Shale
Answer: b
Clarification: Mylonite is also called as micro-breccia and is similar to fault breccia but contains very fine-grained broken particles from the involved rocks that get thoroughly cemented and compacted.

6. The finely pulverized, clay-like powdered rock material is ___________
a) Gouge
b) Fault breccia
c) Mylonite
d) Illite
Answer: a
Clarification: Gouge is finely pulverized, clay-like powdered rock material, which occurs at or near the base of the faulted zones.

7. The evidence of slickensides is easily observed in old faults.
a) True
b) False
Answer: b
Clarification: The evidence of slickensides may be expected only on the recently faulted surfaces because in the old faults such an evidence is more likely to be removed by subsequent weathering.

8. Identify the type of slip from the figure below.

a) Strike slip
b) Dip slip
c) Oblique slip
d) Throw slip
Answer: b
Clarification: The displacement has essentially taken place along the dip of the fault. Hence the figure represents dip slip.

9. Identify the part labelled as “A” in the figure below.

a) Throw
b) Slickensides
c) Heave
d) Offset
Answer: b
Clarification: The part “A” is clearly bearing the evidence of frictional rubbing against each other suffered by them during the process of displacement due to faulting. Hence it is showing slickensides.

10. Gouge and fault breccia are both in finely powdered form.
a) True
b) False
Answer: b
Clarification: Gouge is the finely powdered form but faulted breccia is not. Faulted breccia is crushed angular, fragmentary material produced during faulting, especially when the rocks are brittle and hard.

11. Identify the region marked as “OP2”.
a) Slip
b) Throw
c) Heave
d) Strike
Answer: c
Clarification: Heave is the horizontal component of dip separation measured in a direction perpendicular to the strike of the fault in a vertical plane.

Engineering Geology Multiple Choice Questions & Answers on “Physical Properties – 04”.

1. The property of a mineral by virtue of which it can be cut with a knife is __________
a) Parting
b) Sectile
c) Malleable
d) Ductile
Answer: b
Clarification: The behaviour of a mineral towards the forces that tend to break, bend, cut or crush is described by the term tenacity. Thus, when a mineral can be cut with a knife, it is described as sectile.

2. Mica is __________
a) Flexible
b) Rigid
c) Flexible and elastic
d) Elastic
Answer: c
Clarification: Some minerals are not only flexible but elastic, that is, they regain their shape when the force applied on them is removed. Micas are the best example. Hence they are both flexible and elastic.

3. When the mineral occurs in flattened or square form, it is called __________
a) Tabular
b) Elongated
c) Batroidal
d) Box
Answer: a
Clarification: The mineral occurs in the form of a flattened, square, rectangular or rhombohedral shape if it is said to be tabular. In other words, flattening is conspicuous compared to lengthwise elongation.

4. Example for elongated structure is __________
a) Calcite
b) Beryl
c) Orthoclase
d) Barite
Answer: b
Clarification: When the mineral is in the form of a thin or thick elongated, column-like crystals, it is said to be elongated. For example, Beryl.

5. Kyanite shows which form?
a) Columnar
b) Elongated
c) Bladed
d) Tabular
Answer: c
Clarification: The mineral appears as if composed of thin, flat, blade-like overlapping or juxtaposed parts, if it said to be bladed. Example: Kyanite.

6. Structure or form which depicts leaf-like sheets is __________
a) Foliated
b) Lamellar
c) Radiating
d) Granular
Answer: b
Clarification: The mineral is made up of relatively thick, flexible, leaf-like sheets, if it is said to be lamellar. Example: Vermiculite.

7. Muscovite mica shows which structure?
a) Lamellar
b) Foliated
c) Fibrous
d) Radiating
Answer: b
Clarification: The foliated structure is similar to lamellar in broader sense but in this case, the individual sheets are paper thin, even thinner and can be easily separated. Example: Muscovite mica.

8. Identify the type of structure shown below.
a) Lamellar
b) Foliated
c) Radiating
d) Granular
Answer: c
Clarification: The mineral is made up of needle like or fibrous crystals which appear originating from a common point thereby giving a radiating appearance, if it is said to be radiating. Example: Iron pyrites.

9. Chromite shows which type of structure?
a) Granular
b) Globular
c) Reniform
d) Mammillary
Answer: a
Clarification: The mineral occurs in the form of densely packed mass of small garin-like crystals, in the case of globular structure. Example: Chromite.

10. Which form resembles a human kidney?
a) Globular
b) Reniform
c) Granular
d) Mammillary
Answer: b
Clarification: Reniform is similar to globular but the shape of the bulbs or projections resembles to human kidneys. Example: Hematite.

11. Malachite shows which type of structure?
a) Reniform
b) Globular
c) Mammillary
d) Granular
Answer: c
Clarification: Mammillary is similar to globular but the projections are conspicuous in size, overlapping in arrangement and rounded in shape, best example is malachite.

12. The SI unit of specific gravity is __________
a) Ohm
b) g/cc
c) N/cc
d) No unit
Answer: d
Clarification: Specific gravity is the ratio between the density of a mineral and that of water at 4° Celsius. Since it is a ratio, it has no units.

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

1. Breccia is formed by which process?
a) Mechanical
b) Chemical
c) Organic
d) Residual
Answer: a
Clarification: Breccia is a mechanically formed sedimentary rock classed as rudite. It consists of angular fragments of heterogeneous composition.

2. The type of Breccia which is also called crush-breccia is ____________
a) Basal Breccia
b) Faulted Breccia
c) Agglomeratic Breccia
d) Rudite Breccia
Answer: b
Clarification: Faults Breccia is also called crush-breccia. Such rocks are so named because they are made up of angular fragments that have been produced during the process of faulting.

3. The type of Breccia formed by sea water is called ____________
a) Basal Breccia
b) Faulted Breccia
c) Agglomeratic Breccia
d) Rudite Breccia
Answer: a
Clarification: This rock is formed by the sea waters advancing over a coastal region covered with fragments of chert and other similar rocks.

4. Conglomerates belong to which group of sedimentary rocks?
a) Rudaceous rocks
b) Argillaceous rocks
c) Arenaceous rocks
d) Any group
Answer: a
Clarification: Conglomerates are sedimentary rocks of clastic nature and also belong to rudaceous group.

5. Conglomerates consist of which shaped fragments mostly?
a) Angular
b) Sub-angular
c) Rounded
d) Edged
Answer: c
Clarification: The conglomerates consist mostly of rounded fragments of various sizes but generally above 2 mm, cemented together in clayey or ferruginous or mixed matrix.

6. Which among the following is not a type of conglomerate?
a) Basal
b) Glacial
c) Volcanic
d) Faulted
Answer: d
Clarification: Sometimes the conglomerates are distinguished on the basis of source of the gravels, as: Basal, glacial and volcanic conglomerates.

7. The sedimentary rock which is arenaceous in nature is ____________
a) Conglomerate
b) Sandstone
c) Breccia
d) Shale
Answer: b
Clarification: Sandstones are mechanically formed sedimentary rocks of arenaceous group. These are mostly composed of sand grade particles that have been compacted and consolidated together in the form of beds in basins sedimentation.

8. Which is the dominant mineral in sandstone?
a) Mica
b) Diamond
c) Quartz
d) Felspar
Answer: c
Clarification: Quartz is the most common mineral making the sandstones. In fact some varieties of sandstones are made entirely of quartz.

9. The texture of sandstone is ____________
a) Fine-medium
b) Medium-coarse
c) Coarse
d) Fine-coarse
Answer: a
Clarification: Sandstones are, in general, medium to fine-medium grained in texture. The component grains show a great variation in their size, shape and arrangement in different varieties.

10. The colour of sandstone not found commonly is ____________
a) Blue
b) Red
c) Brown
d) White
Answer: a
Clarification: Sandstones naturally occur in a variety of colours: red, brown, grey and white being the most common colours. The colour of sandstone depends on its composition, especially the nature of the cementing material.

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

1. Which of the following doesn’t control aquifer behaviour?
a) Wind conditions
b) Nature of the rock
c) Structural disposition
d) Climate conditions like precipitation
Answer: a
Clarification: As a storage reservoir, the aquifer behaviour is controlled by- the nature of the rock and its porosity, structural disposition, with regard to the recharge points or places, climate conditions like annual precipitation.

2. An aquifer can hold water _________ and the state of water is _________
a) Permanently – State of flow
b) Temporarily – State of flow
c) Permanent – State of stagnancy
d) Temporary – State of stagnancy
Answer: b
Clarification: It must be remembered that an aquifer can hold water only temporarily, as the water is always in a state of flow in it. However, the rate of flow of water through an aquifer is very slow compared to surface waters.

3. Groundwater is a subordinate to surface water.
a) True
b) False
Answer: b
Clarification: The importance of groundwater in water supply system can hardly be over emphasized. It is in no way subordinate to that of surface waters.

4. The quantity of water that can be withdrawn annually and also the rate at which this withdrawal could be made without adversely affecting the inventory of the aquifer is called __________
a) Annual yield
b) Percent yield
c) Operational yield
d) Monthly yield
Answer: c
Clarification: The quantity of water that can be withdrawn annually and also the rate at which the withdrawal could be made without adversely affecting the inventory of the aquifer, therefore, determine what may be called operational yield.

5. When an aquifer is used to artificially recharge by making it pass through an intervening layer, the aquifer acts as __________
a) A cooling agent
b) An aerating agent
c) An odour agent
d) A filter plant
Answer: d
Clarification: An aquifer may be made to serve as a filter plant when artificial recharge is made to pass through an intervening layer of rock, which acts as a natural filter.

6. When would the dam become irrelevant?
a) When the rocks are strong
b) When the rocks are impermeable
c) When the rocks are porous
d) When the rocks are weathered to a certain extent
Answer: c
Clarification: A dam is built across a river primarily to store water in the form of a reservoir. The whole idea of a dam would become irrelevant if the foundations on which it is built are made of porous rocks or if a stretch of a reservoir rock is permeable.

7. Which quality of rock should be known properly for the foundations of dams, reservoirs, etc.?
a) Colour knowledge
b) Geological
c) Hydrogeological
d) History of the formation of rocks
Answer: c
Clarification: The position of the water table and hydrogeological qualities of rocks forming foundations and abutments of dams and reservoirs must be known.

8. Groundwater is a source of trouble at which place?
a) Plains
b) Slopes
c) Rivers
d) Lakes
Answer: b
Clarification: Groundwater is a major source of trouble for the stability of slopes. Many slope failures, especially in hilly regions are due to direct or indirect involvement of groundwater.

9. An associated protection of rising water-table is the development of __________
a) Loss of nutrients
b) Loss of good quality of water
c) Salinity of water
d) Increase in turbidity
Answer: c
Clarification: An associated trouble with rising water-table is the development of salinity of the soils. The rising groundwater may be rich in some undesirable salts that are left at or near the surface during its loss to atmosphere due to evaporation.

10. The root system of crops in water-logged areas get __________
a) Decomposed
b) Enriched with nutrients
c) Photosynthesised
d) Growth inhibited
Answer: a
Clarification: The root system of crops in water-logged areas gets decomposed. Large areas of land in Indian subcontinent are affected by water-logging.

11. The lubricating action of water is a positive action for slope rocks.
a) True
b) False
Answer: b
Clarification: Soil creep and solifluction are caused mainly due to groundwater. The lubricating action of water besides its negative effect on the strength parameters of rocks is the major cause in initiating massive landslides.

Engineering Geology Multiple Choice Questions on “Geological Investigations”.

1. Selection of excavation method depends on __________
a) Type of rocks
b) Nature of rocks and ground
c) Texture of rocks and ground
d) Weather conditions of the place
Answer: b
Clarification: Choice of the right method will, therefore, be possible only when the nature of the rocks and the ground all along the alignment is fully known. This is one of the most important aim and objects of geological investigations.

2. Which outline is preferred for weak rocks with unequal lateral pressure?
a) D-shaped
b) Horse-shoe shaped
c) Circular
d) Rectangular shaped
Answer: c
Clarification: In self-supporting and strong rocks, either, D-shape or horse-shoe shape may be conveniently adopted but these shapes would be practically unsuitable in soft ground or even in weak rocks with unequal lateral pressure. In those cases, circular outline may be the first choice.

3. Lithology does not affect which parameter?
a) Type of tunnel
b) Method of tunnelling
c) Strength and extent of lining
d) Cost of the project
Answer: a
Clarification: Information regarding mineralogical composition, textures and structures of the rocks through which the proposed tunnel is to pass is of great importance in deciding: the method of tunnelling, the strength and extent of lining and, thus the cost of the project.

4. What occurs due to falling of big rock blocks or sides due to release of stresses during tunnelling?
a) Rock fall
b) Rock bursts
c) Blockage
d) Water rush
Answer: b
Clarification: Rock bursts that occur due to falling of big rock blocks from roofs or sides due to the release of stresses or falling of rock block along fractures already existing in these rocks often cause many accidents.

5. Pick the rock considered as soft rocks for tunnelling.
a) Granite
b) Gabbro
c) Basalt
d) Shale
Answer: d
Clarification: Rocks considered as hard and crystalline are granites, syenites, gabbros, basalts and all the related igneous rocks, sandstones, limestones, dolomites, quartzites etc. However the soft rocks include shales, friable and poorly compacted sandstones, chalk and porous varieties of limestones and dolomites, slates and phyllites with high degree of cleavage.

6. Which type of rocks requires double lining, i.e., temporary and permanent lining?
a) Hard rocks
b) Crystalline rocks
c) Soft rocks
d) Non-crystalline rocks
Answer: c
Clarification: In most cases, the soft rocks are not self-supporting. Hence, temporary and permanent lining becomes necessary that would involve extra cost and additional time.

7. Which type of strata is rare in occurrence?
a) Vertical strata
b) Horizontal strata
c) Inclined strata
d) Jointed strata
Answer: b
Clarification: Horizontal strata are rare in occurrence for longer tunnels. If they are countered for small tunnels or short lengths of long tunnels, horizontally layered rocks might be considered quite favourable.

8. Layers dipping at angles up to 45° may be called __________
a) Moderately inclined strata
b) Steeply inclined strata
c) Half inclined strata
d) Semi-inclined strata
Answer: a
Clarification: The layers that dipping at angles up to 45° may be said as moderately inclined strata. The tunnel axis may be running parallel to the dip direction, at right angles to the dip direction or inclined to both dip and strike direction.

9. When can the rocks act as a natural arch?
a) Tunnel axis parallel to dip direction
b) Tunnel axis normal to dip direction
c) Tunnel axis inclined to dip direction
d) Tunnel axis parallel to strike direction
Answer: a
Clarification: When the tunnel axis may be running parallel to the dip direction, the layers offer uniformly distributed load on the excavation. The arch action is said to happen, where the rocks at roof act as natural arches transferring the load onto sides.

10. In synclinal condition, low pressure areas are found at __________
a) Core
b) Crust
c) Mantle
d) Outline
Answer: b
Clarification: In anticlinal folds, loads of rocks at the crust are transferred by arch action to a great extent to the limbs which may be highly strained. These conditions are reversed in synclinal folds. In such cases, rocks of core regions are greatly strained.

11. Which of the following is not included under preliminary survey?
a) Knowing the general topography of the area
b) Knowing the lithology of the area
c) Knowing the structural condition of the rocks
d) Driving the pilot tunnels
Answer: d
Clarification: The preliminary surveys include: Knowing the general topography, the lithology, hydrological conditions in the area and structural condition of the rocks. Driving pilot tunnels, bore-hole drilling are considered under detailed surveys.

12. Folded rocks are often best storehouses of which of water?
a) Juvenile water
b) Magmatic water
c) Artesian water
d) Connate water
Answer: c
Clarification: Folded rocks are often best storehouses for artesian water and also ideal as aquifers. When encountered during tunnelling unexpectedly, these could create uncontrollable situations.

13. Which type of geological structure can be rectified by grouting?
a) Joints
b) Folds
c) Faults
d) Inclined strata
Answer: a
Clarification: In many cases, problems created by jointing in rocks due to jointing can be grouting. In other cases, lining of the tunnel in the fractured zones might have to be applied.

14. The pressure of the tunnel axis below the water table is preferable.
a) True
b) False
Answer: b
Clarification: The tunnel axis might be located below the water table. Such a situation should be avoided as far as possible.

Engineering Geology Multiple Choice Questions on “The Crust”.

1. What is the thickness of the crust under the mountainous areas and in particular the Himalayas?
a) 50-55 km
b) 60-65 km
c) 70-75 km
d) 30-35 km
Answer: c
Clarification: It is believed that the thickness of the crust under the Himalayas is 70 to 75 km and under the Hindukush it is said to be 60 km thick.

2. The discontinuity which marks the lower boundary of the crust is ______________
a) Crust-Mantle discontinuity
b) Oceanic discontinuity
c) SIAL layer
d) Mohorovicic discontinuity
Answer: d
Clarification: Mohorovicic discontinuity marks the lower boundary of the crust which is the first layer of the Earth.

3. The granite layer in the crust is also referred to as ____________
a) SIAL
b) SIMA
c) SLAM
d) SILA
Answer: a
Clarification: SIAL stands for Silicon and Aluminium and as per the name it is made up of the two elements and hence the name.

4. The density of the oceanic layer in the crust is said to be ____________
a) 3.00 g/cc
b) 2.50 g/cc
c) 1.90 g/cc
d) 2.00 g/cc
Answer: a
Clarification: The oceanic crust is estimated to have a volume of 2.54*109 cc with an average density of 3.00 g/cc.

5. The depth at which the Mohorovicic discontinuity occurs is ____________
a) 90-100 km
b) 50-60 km
c) 70-80 km
d) 30-40 km
Answer: d
Clarification: Mohorovicic discontinuity from seismic evidence is determined that it is approximately at a depth of 30-40 km.

6. What is the speed attained by the P-waves in the C-layer under the Continental crust?
a) 6 to 7.6 km/sec
b) 3 to 4 km/sec
c) 5 to 6.3 km/sec
d) 1.8 to 2.5 km/sec
Answer: a
Clarification: The C-layer is the lowermost layer of the continental crust and here the P-waves attain velocity as high as 6 to 7.6 km/sec.

7. The layer under the continental crust with the density of 2.4 to 2.6 g/cc is?
a) A-layer
b) B-layer
c) C-layer
d) D-layer
Answer: b
Clarification: The Middle layer or B-layer of the continental crust is relatively dense compared to A-layer and the density is said to be 2.4 to 2.6 g/cc.

8. The expansion of SIMA is ____________
a) Silicon and Manganese
b) Silicon and Magnesium
c) Strontium and Manganese
d) Strontium and Magnesium
Answer: b
Clarification: Silicon and Magnesium. The C-layer under the continental crust is rich in Silicon and Magnesium and hence the layer is also sometimes called SIMA.

9. The oceanic layer is the extension of C-layer of the continental crust and A and B-layer are mostly absent.
a) True
b) False
Answer: a
Clarification: The oceanic crust is the extension of C-layer of the continental crust that makes the top layer of the oceans in most cases, A and B layers being practically absent from there.

10. The least dense layer among the layers under the continental crust is ____________
a) A-layer
b) B-layer
c) C-layer
d) D-layer
Answer: a
Clarification: The A or the upper layer is between 2 to 10 km thick and is of low density, 2.00 g/cc.

11. The area not considered under the crust is ____________
a) Mountainous area
b) Continental area
c) Oceanic area
d) Glacial area
Answer: d
Clarification: The first the options, Mountainous, Continental and Oceanic areas are studied separately whereas Glacial area is not considered under study of the crust as such.