Geomorphology MCQ Quiz - Objective Question with Answer for Geomorphology - Download Free PDF

The correct answer is aquifer.

Key Points

• The groundwater stored between layers of hard rock below the water table is called aquifer.
• An aquifer is a saturated zone beneath the water table.
• It is a body of porous rock or sediment saturated with groundwater.
• Groundwater enters an aquifer as precipitation seeps through the soil.
• It can move through the aquifer and resurface through springs and wells.
• There are two general types of aquifers: confined and unconfined.
  • Confined aquifers have a layer of impenetrable rock or clay above them, while unconfined aquifers lie below a permeable layer of soil. 
• Aquifers are typically made up of gravel, sand, sandstone, or fractured rock, like limestone.
• Water can move through these materials because they have large connected spaces that make them permeable.

Additional Information

• Groundwater resources:
  • ​It is the water found underground in the cracks and spaces in soil, sand, and rocks.
  • It is stored in and moves slowly through the geological formation of soil, sand, and rocks called aquifers.
  • The total replenishable groundwater resources in the country are about 432 cubic km.

The correct answer is coffee.

Key Points

• There are over 100 species of the genus Coffee in the world, and all are native to tropical Africa and some Indian Ocean islands.
• Two species, C. arabica and C. canephora, are commonly grown commercially.
  • Coffea canephora is commonly referred to as “robusta” and makes up about 25 to 40% of the coffee grown for consumption.
• Robusta grows in hotter (22 to 26ºC), more humid climates than arabica coffee (18–21ºC), and at lower elevations (from about 200 to 900 m).
• Robusta has a higher caffeine content (30 to 50% more) than arabica.
• Arabica coffee is self-pollinating, robusta requires cross-pollination by insects or wind.

Additional Information

•  Santos port in Brazil is known as "Coffee Port of the world".
• It is located in state of Sao Paulo.

The correct answer is option 2.

Key Points

• A hanging valley is a glacial landform formed when a smaller tributary glacier meets a deeper main glacier valley. Hence, option 2 is correct.
• After the glaciers retreat, the tributary valley is left “hanging” above the main valley, often forming waterfalls.
• This feature is characteristic of glaciated mountainous regions.

The correct answer is option 2.

Key Points

• Epeirogenic movements refer to broad, gentle, vertical movements of the Earth's crust. Hence, option 2 is correct.
• These movements cause uplift or subsidence of large land areas without significant folding or faulting.
• Unlike orogenic forces (which involve horizontal compressional forces leading to mountain building), epeirogenic forces result in vertical adjustments.

The correct answer is Tropical Deciduous Forests.

Important Points

• Tropical deciduous forests are also called monsoon forests because the trees in these forests shed their leaves during the dry season and re-grow during the monsoon.

Key Points

• Tropical Evergreen Forests:
  • These types of forests are found in the equatorial and tropical regions with more than 200 cms annual rainfall.
  • The leaves of trees in such forests are very wide.
  • Example: Mahogany, Redwood, Palm, etc. 
• Tropical Deciduous Forests:
  • These are popularly known as monsoon forests.
  • The trees in these types of forests shed their leaves during the dry season and re-grow during the monsoon.
  • These types of forests receive rainfall in the range of 70-200 cms.
  • These types of forests are further classified as Moist Deciduous Forests and Dry Deciduous Forests.
• Montane Forests:
  • In these types of forests, vegetation varies according to altitude.
• Mangrove forests:
  • These are formed along the banks of river estuaries.
  • These are also called Tidal Forests.
  • Mangrove forests of Sundarbans are the largest mangrove forests in the world.  

The correct answer is outer core.

Important Points

• The interior of the earth is divided into three parts namely Crust, Mantle, and Core.
• The core is the innermost layer of the earth.
• The radius of the innermost layer(core) is about 3500 km.
• The core is made up of material constituted by nickel and iron.
• The temperature and pressure of the central core are very high.

Key Points

• The core is further subdivided into two layers called the outer core and inner core.
• The outer core of the earth is in a liquid state.
• The inner core is in solid-state
• The outer core is responsible for the earth's magnetic field.

Additional Information

• The crust is the outermost of the earth.
  • It is brittle in nature.
  • it the thinnest layer of Earth.
  • The thickness of the crust varies under the oceanic and continental areas.
• The mantle is the second layer in the interior of the earth.
  • The mantle extends from Moho’s discontinuity to a depth of 2,900 km.
  • The upper portion of the mantle is called the asthenosphere.

The correct answer is 4.

Important Points

• Based on historical seismic activity, the Bureau of Indian Standards has categorized regions in India into four seismic zones: zones II, III, IV and V.
• Of these, the most seismically active area is Zone V and the least active is Zone II. 
• There is a history of devastating earthquakes on the Indian subcontinent.
• The key cause for the high frequency and severity of earthquakes is that the Indian plate is driving into Asia at a rate of roughly 47 mm/year.
• India's geological figures indicate that about 54 percent of the land is prone to earthquakes.
• Research by the World Bank and the United Nations predicts that by 2050, about 200 million urban dwellers in India will be vulnerable to storms and earthquakes.
• The most recent edition of India's seismic zoning map given in India's earthquake-resistant design code [IS 1893 (Part 1) 2002] assigns four degrees of seismicity in terms of zone factors for India.
• In other words, unlike its previous edition, which consisted of five or six zones for the region, India's earthquake zoning map divides India into four seismic zones (Zone 2, 3, 4, and 5).
• According to the new zoning map, the maximum degree of seismicity is predicted in Zone 5, while the lowest level of seismicity is correlated with Zone 2.

Revised earthquake hazard zone map of India

Option 2 is correct, i.e. Aluminium.

Key Points

• Aluminium is the most plentiful (most abundant) of metals in the crust of the earth.
• Aluminium is around 8.1 per cent of the total metals on the surface of the earth.

Important Points

• The most plentiful non-metal in the earth's surface is Oxygen.
• The most plentiful metalloid in the crust of the earth is Silicon.
• O > Si > Al > Fe > Ca are the most abundant elements in the earth crust.

• Block mountains are the type of mountains in which the middle part of the mountain is lower and the parts on both sides are higher. 
• The middle part is known as the rift valley. 
• Black Forest (Germany), Salt Range (Pakistan), Vindhya and Satpura (India) are examples of block mountains. 
• The Ural is a fold mountain. Fold mountains are formed because of folds in the rocks due to the internal movements of the earth. 
• Block mountains - 

The correct answer is L waves.

Key Points

• L waves, or Love waves, are one type of surface wave in seismic activity.
  • Named after British mathematician A.E.H. Love, who first mathematically predicted their existence.
  • Love waves move the ground from side to side in a horizontal plane perpendicular to the direction of propagation.
  • As they travel along the Earth's surface, they cause horizontal shearing and produce entirely horizontal motion.
  • L waves are the slowest of all seismic waves and therefore the last to be recorded by seismographs.
  • These waves are particularly damaging to the foundations of structures due to their horizontal motion.

Additional Information

• P waves:
  • P waves, or Primary waves, are body waves that travel through the interior of the Earth.
  • They are the fastest seismic waves and thus the first to be detected by seismographs.
  • P waves cause particles to move in the same direction as the waves, creating a push-and-pull motion.
• S waves:
  • S waves, or Secondary waves, are also body waves that move through the Earth's interior.
  • They are slower than P waves but faster than surface waves.
  • S waves cause particles to move perpendicular to the wave direction, creating an up-and-down or side-to-side motion.
• R waves:
  • Also known as the Rayleigh wave.
  • It has both compressional and shear motions.
  • These waves result from the interaction of P-waves and vertically polarized S-waves with the surface and can exist in any solid medium.

The correct answer is 30 km.

Key Points

• Earth’s crust:
  • The interior of the earth is made up of several concentric layers which are the crust, the mantle, the outer core and the inner core.
  • The crust is the outermost layer of the earth making up 0.5-1.0% of the earth’s volume and less than 1% of Earth’s mass.
  • Materials that initially stayed in their liquid phase during this process, called “incompatible elements,” ultimately became Earth's brittle crust. 
  • The lower layer of the crust consists of basaltic and ultra-basic rocks.
  • Density increases with depth, and the average density is about 2.7 g/cm3 (the average density of the earth is 5.51 g/cm³).
  • The thickness of the crust varies in the range of 5-30 km in the case of the oceanic crust and 50-70 km in the case of the continental crust.
  • The mean thickness of the oceanic crust is approximately 7 km, while the mean thickness of the continental crust is about 35-40 km.

Important Points

The correct answer is sedimentary rock.

Important Points

• Sedimentary rocks are formed by deposition, sedimentation, and lithification of sediments over a long period of time.
• Sedimentary rocks may also contain fossils of plants, animals that once lived on them.
• The word ‘sedimentary’ is derived from the Latin word "sedimentum".
• Shale, limestone, and conglomerate are some other examples of sedimentary rocks.

Key Points

• Sandstone is an example of sedimentary rock.
• Sandstone is made from grains of sand.

Additional Information 

• A rock is an aggregate of one or more minerals.
• Igneous rock is formed due to the cooling, solidification, and crystallization of hot and molten magma.
  • Granite, Basalt, Gabbro are examples of Igneous rocks.
• Metamorphic rocks are made up of sedimentary rock and igneous rock which have been subjected to high pressure and temperature.
  • Clay changes into slate and limestone into marble are the examples of metamorphic rocks.
• Marble and quartzite are examples of non-foliated metamorphic rocks.

The correct answer is Sandstone.

• Sandstone is NOT a metamorphic rock.

Key Points

• Metamorphic rocks are rocks that have become changed by intense heat or pressure while forming.
  • In the very hot and pressured conditions deep inside the Earth's crust, both sedimentary and igneous rocks can be changed into metamorphic rock.
  • ​Metamorphic rock can be formed locally when rock is heated by the intrusion of hot molten rock called magma from the Earth's interior.
    • Some examples of metamorphic rocks are gneiss, slate, marble, schist, and quartzite.
  • Marble, Slate, and quartz are formed after metamorphism. They changed in their original form due to extreme temperatures and pressure.
  • The three types of metamorphism are Contact, Regional, and Dynamic metamorphism.
  • Contact Metamorphism occurs when magma comes in contact with an already existing body of rock.

Additional Information

• Sandstone :
  • Sandstone is a sedimentary rock composed of sand-size grains of mineral, rock, or organic material.
    • It also contains a cementing material that binds the sand grains together and may contain a matrix of silt- or clay-size particles that occupy the spaces between the sand grains.
  • Sandstone is a sedimentary rock composed mostly of quartz sand, but it can also contain significant amounts of feldspar, and sometimes silt and clay.
  • Sandstone that contains more than 90% quartz is called quartzose sandstone.

The correct answer is Increases

Key Points

• A rise in temperature with an increase in depth is observed in mines and deep wells.
• These evidence along with molten lava erupted from the earth’s interior supports that the temperature increases towards the centre of the earth.
• While in the upper 100kms, the increase in temperature is at the rate of 120C per km and in the next 300kms, it is 200C per km. But going further deep, this rate reduces to a mere 100C per km.
• It is assumed that the rate of increase in the temperature beneath the surface is decreasing towards the centre.
• Temperature is always increasing from the earth’s surface towards the centre.
• The temperature at the centre is estimated to lie somewhere between 30000C and 50000C, maybe that much higher due to the chemical reactions under high-pressure conditions.

​

The correct answer is i - b, ii - a, iii - c

Key Points

Lithification:

• It refers to the process by which loose and under-consolidated sediment particles transform into hard and solid rocks.
• This process includes a number of geological processes, such as consolidation, deep bury, cementation, recrystallization, and dehydration.

Igneous Rocks:

• As igneous rocks form out of magma and lava from the interior of the earth, they are known as primary rocks.
• The igneous rocks (Ignis – in Latin means ‘Fire’) are formed when magma cools and solidifies.
• When magma in its upward movement cools and turns into a solid form it is called igneous rock.
• The process of cooling and solidification can happen in the earth’s crust or on the surface of the earth.
• Igneous rocks are classified based on texture which depends upon the size and arrangement of grains or other physical conditions of the materials.
• Granite, gabbro, pegmatite, basalt, volcanic breccia, and tuff are some examples of igneous rocks.

Sedimentary Rocks

• The word ‘sedimentary’ is derived from the Latin word sediment, which means settling.
• Rocks (igneous, sedimentary, and metamorphic) of the earth’s surface are exposed to denudational agents and are broken up into various sizes of fragments.
• Such fragments are transported by different exogenous agencies and deposited.
• These deposits through compaction turn into rocks.
• In many sedimentary rocks, the layers of deposits retain their characteristics even after lithification.
• Hence, we see a number of layers of varying thickness in sedimentary rocks like sandstone, shale, geyserite, chalk, limestone, coal etc.

Metamorphic Rocks

• Metamorphic means ‘change of form’.
• These rocks form under the action of pressure, volume, and temperature (PVT) change.
• Metamorphism occurs when rocks are forced down to lower levels by tectonic processes or when molten magma rising through the crust comes in contact with the crustal rocks or the underlying rocks are subjected to great amounts of pressure by overlying rocks.
• Metamorphic rocks are formed due to the proximity of sedimentary rocks with molten magma.
• Mechanical disruption and reorganization of the original minerals within rocks due to breaking and crushing without any appreciable chemical changes are called dynamic metamorphism.
• Examples- Marble, Quartzite, Schist, etc.

Additional Information

Foliation:

• In the process of metamorphism in some rocks grains or minerals get arranged in layers or lines.
• Such an arrangement of minerals or grains in metamorphic rocks is called foliation or lineation.