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MCQs on Geology

MCQs on "Geology ": Find the multiple choice questions on "Geology ", frequently asked for all competitive examinations.

Geology is the study of the composition of the Earth’s surface and under it and the events that have shaped it. It also includes methods for determining the absolute and relative ages of rocks discovered in a certain place and describing the rock’s history. Geologists may document the geologic Earth’s history and show the age of rocks by combining these technologies. Plates’ continental drift, the long evolution of species, and the Earth’s previous temperatures are all supported by geology.

Recognising the progression of life on Earth, exploring assets such as metallic materials and power, recognising and minimising the environmental consequences of using certain resources, and acquiring knowledge on minimising the dangers prone to natural disasters, volcanism, and landslides are all part of geology.

Multiple Choice Questions

1. The S-wave comes to an end at:

    1. A barrier between the crust and the mantle
    2. The border between the lithosphere and the asthenosphere
    3. The border between the mantle and the core
    4. Core Boundaries (Inner and Outer)

Answer – C

Inside Earth, waves are reflected at the Moho, the core-mantle boundary (, and the outer-core/inner-core boundary, among others. S-waves do not pass-through liquids and are halted at the core-mantle barrier, and an S-wave shadow could be seen on the side of the Earth opposite a seismic source.

2. The following factors are hypothesised to be involved in plate movement:

    1. Isostasy
    2. Earth’s rotation
    3. Thermal convection cells
    4. Polar wandering

Answer: (C)

Convection in the mantle propels the movement of tectonic plates. Convection is the concept that dense, cold objects sink while buoyant, warm objects ascend. Slabs are cold sinking items in the earth, while plumes, or simply emerging matter from deep in the mantle, are warm sinking things.

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3. The element which is most widespread in the earth’s crust is:

    1. Oxygen
    2. Silicon
    3. Aluminium
    4. Iron

Answer: (A)

Oxygen is the most prevalent component in the Earth’s crust, accounting for 46 per cent of the total mass—just shy of half.

4. The following is the name of the instrument used to record earthquake waves:

    1. Seismograph
    2. Seismogram
    3. Seismometer
    4. Scintillometer

Answer: (A)

Seismographs are devices that record the ground’s movement during an earthquake. They are used as a component of a seismological system and are put in the soil worldwide.

5. At the magnetic pole, the cosmic radiation strength is at its lowest:

    1. Equator
    2. North pole
    3. South pole
    4. Tropic of cancer

Answer: (A)

The intensity of ionising cosmic rays is higher in the polls than in equatorial regions due to the Earth’s magnetic field structure. This is due to the Earth’s field lines guiding cosmic rays to the poles. The flow of cosmic ray strength changes with altitude as well. After that first collision, the placed beneath flow peaks at 16 km height.

6. What is the source of energy for the Earth’s internal heat engine?

    1. Solar energy
    2. Ocean tides
    3. Volcanoes
    4. Radioactivity

Answer: (D)

The heat flow from Earth’s interior towards the top is believed to be in the terawatt range. It comes from two primary sources in nearly equal amounts: radiogenic heat created by the radioactivity of isotopes in the mantle and crust and primordial heat leftover from Earth’s birth.

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7. The following factors contribute to the accumulation of oxygen in the Earth’s atmosphere:

    1. Formation of the ocean in the early history of Earth
    2. Algae and other organisms employed photosynthesis
    3. Oxygen settled on Earth from planets further from the sun
    4. Rocks weathered and released their oxygen.

Answer: (B)

The solution is cyanobacteria, or blue-green algae, which are small creatures. Photosynthesis is a process in which bacteria use sunlight, water, and co2 to make carbs and oxygen. To this day, all plants on the planet rely on symbiotic cyanobacteria to perform photosynthesis for them.

8. As a consequence of global warming, there may be an increase in sea level as a result of:

    1. A Melting of ice-caps
    2. Thermal expansion of seawater
    3. Both A. and B.
    4. Isostatic rebound

Answer: (C)

Over the previous two and a half decades, the average sea level has increased roughly 21–24 cm, with around a quarter of it occurring within the last two decades. The increasing water level is mostly due to a mix of glacial melt from glaciers and ice sheets and the thermal expansion of warm saltwater.

9. The ozone layer in the Earth’s atmosphere is limited to the following areas:

    1. A Troposphere
    2. Stratosphere
    3. Mesosphere
    4. Thermosphere

Answer: (B)

The ozone layer is found between 15 and 30 kilometres above the earth’s surface in the stratosphere. It absorbs the majority of the sun’s ultraviolet energy, limiting the amount that reaches earth.

10.What are the cracks along with those blocks that have moved relative to one another?

    1.  Folds
    2.  Joints
    3.  Faults
    4.  Intrusions

Answer: C

Those cracks across which there seems to be the relative motion of a block passed one another says the definition of faults. Faulting refers to the complete process of fracture formation and block migration against one another.

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11. When some grains are huge, and just a few are little, what is the terminology used?

    1. Mixed granular
    2. Equigranular
    3. Inequigranular
    4. Unequigranular

Answer: C

When all of the constituent minerals present have roughly similar dimensions, the texture is described as equigranular; when certain elements inside the bedrock are much bigger or smaller, the texture is described as equigranular.

12. Choose the incorrect granitic texture statement.

    1. The constituents are coarse-grained
    2. The constituents are medium-grained
    3. The crystals show euhedral to subhedral outlines
    4. The rock is microgranular

Answer: (d)

Because lava gradually cools, granites often have a coarse texture, enabling bigger crystal formation. Individual crystals are evident without magnification. Due to delayed cooling under the surface, granites are easily identified as light-coloured and coarse-grained.

13. The field of geology that deals with the form, classification, mechanism, and causes of these rock structures’ evolution are known as

    1. Rock geology
    2. Structural geology
    3. Basic geology
    4. Lithology

Answer: B

Structural geology is a branch of geology exploring how rocks bend in reaction to forces within the Earth’s interior. Rocks and their developing elements accept and record the pressures on them by generating cracks, faults, and folds, which are sometimes quite stunning geological formations.

14. Who among the following rocks has a significant stratification?

    1. Igneous rocks
    2. Metamorphic rocks
    3. Sedimentary rocks 
    4. Fossil rocks

Answer: C

Many sedimentary rocks form under circumstances that encourage the formation of separate layers stacked one on top of either, from bottom to top. These layers are also known as strata or beds.

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15. The most common rock on the planet is __ 

    1. Igneous rock
    2. Sedimentary rock 
    3. Metamorphic rock 
    4. All are found in equal amounts.

Answer: B

Compared to igneous and metamorphic rocks, which develop deep beneath the Earth, sedimentary rocks form on or near the surface. Destruction, weathering, dissolving, rainfall, and lithification are the major geological processes that contribute to the formation of sedimentary rocks.

16. A stratum of rock’s highest angle of inclination the with horizontal is __ 

    1. Dip
    2. Heave angle
    3. Strike 
    4. Depth

Answer: A

The dip is defined as “the highest angle of inclination of a stratum of rock with respect to the horizontal.” It is measured in degrees of inclination as well as directions of inclination.

17. What are the two criteria thought to be necessary for igneous rock formation?

    1. Low temperature and molten state
    2. Molten state and very high-temperature
    3. Molten state and moderate temperature
    4. Crystallised state and moderate temperature

Answer: B

For the primordial material from which igneous rocks are thought to have evolved, a very high temperature and a molten state are two highly important criteria.

18. What is the lava or magma’s current state?

    1. Always liquid
    2. Solid 
    3. Gaseous
    4. Mixture of liquid, crystals, and gases

Answer: D

Magma is the name for molten rock under the Earth’s surface. Lava is molten that erupts from the Earth’s surface. Liquid Magma is another name for lava.

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19. Where do volcanic rocks come from?

    1. Below the surface of the earth
    2. On the surface of the earth 
    3. Inside the cored. Between the mantle and the core

Answer: B

When magma escapes and cools above or very near the Earth’s surface, extrusive or volcanic igneous rock is formed. And those are the rocks that emerge when volcanoes erupt and crevices ooze.

20.The term “magma” refers to a hypothetical melt.

    1. True
    2. False 
    3. It could be True or False 
    4. Can’t say

Answer: A

Magma and lava both contribute to the formation of igneous rocks. It’s worth mentioning that magma is a hypothetical melt. It was not feasible to view it in its natural habitat.