For study the earth can be divided into three parts

Latest Interior structure of the earth MCQ Objective Questions

Interior structure of the earth MCQ Question 1:

Which of the following best describes the Process of Differentiation?

1. It is the process through which different gases were released from the interior of the earth.
2. It is the process through which the interior of the earth was created.
3. It is the process through which stars were formed out of vast galaxies.
4. It is the process of differentiation of various types of rocks.

Answer (Detailed Solution Below)

Option 2 : It is the process through which the interior of the earth was created.

The correct answer is Option 2.

• The earth was mostly in a volatile state during its primordial stage.
• Due to a gradual increase in density the temperature inside has increased. 
• As a result the material inside started getting separated depending on their densities.
• This allowed heavier materials (like iron) to sink towards the centre of the earth and the lighter ones to move towards the surface.
• With the passage of time, it cooled further and solidified and condensed into a smaller size. 
• This later led to the development of the outer surface in the form of a crust. 
• During the formation of the moon, due to the giant impact, the earth was further heated up. It is through the Process of Differentiation that the earth-forming material got separated into different layers. 
• Starting from the surface to the central parts, we have layers like the Crust, Mantle, Outer Core and Inner Core. From the crust to the core, the density of the material increases. So, Option 2 is Correct.

Interior structure of the earth MCQ Question 2:

Which of the following best describes the term ‘Degassing’?

1. The process through which the gases were outpoured from the interior of the earth.
2. It is a process through which primordial temperature was lost through photosynthesis
3. It is a process through which the moon was formed.
4. It is a process by which hydrogen and helium were formed in the atmosphere.

Answer (Detailed Solution Below)

Option 1 : The process through which the gases were outpoured from the interior of the earth.

The correct answer is Option 1.

Evolution of Atmosphere

•  During the cooling of the earth, gases and water vapour were released from the interior solid earth. This started the evolution of the present atmosphere. 
• The early atmosphere largely contained water vapour, nitrogen, carbon dioxide, methane, ammonia and very little free oxygen.
• The process through which the gases were outpoured from the interior is called Degassing. So, Option 1 is Correct.
• Continuous volcanic eruptions contributed water vapour and gases to the atmosphere. 
• As the earth cooled, the water vapour released started getting condensed.
• The carbon dioxide in the atmosphere got dissolved in rainwater and the temperature further decreased causing more condensation and more rains. 
• The rainwater falling onto the surface got collected in the depressions to give rise to oceans. 
• The earth’s oceans were formed within 500 million years from the formation of the earth. This tells us that the oceans are as old as 4,000 million years. 
• Sometime around 3,800 million years ago, life began to evolve.

Interior structure of the earth MCQ Question 3:

Match the following for types of folds :

1. (a) - (iv), (b) - (ii), (c) - (iii), (d) - (i)
2. (a) - (ii), (b) - (iii), (c) - (i), (d) - (iv)
3. (a) - (iii), (b) - (i), (c) - (iv), (d) - (ii)
4. (a) - (i), (b) - (iv), (c) - (ii), (d) - (iii)

Answer (Detailed Solution Below)

Option 3 : (a) - (iii), (b) - (i), (c) - (iv), (d) - (ii)

The correct answer is (a) - (iii), (b) - (i), (c) - (iv), (d) - (ii).

Interior structure of the earth MCQ Question 4:

Match the following for types of folds :

1. (a) - (iv), (b) - (ii), (c) - (iii), (d) - (i)
2. (a) - (ii), (b) - (iii), (c) - (i), (d) - (iv)
3. (a) - (iii), (b) - (i), (c) - (iv), (d) - (ii)
4. (a) - (i), (b) - (iv), (c) - (ii), (d) - (iii)

Answer (Detailed Solution Below)

Option 3 : (a) - (iii), (b) - (i), (c) - (iv), (d) - (ii)

The correct answer is (a) - (iii), (b) - (i), (c) - (iv), (d) - (ii).

Interior structure of the earth MCQ Question 5:

With reference to minerals found in the earth’s crust, consider the following statements:

1. All the minerals are composed of two or more elements.

2. Minerals can be both organic and inorganic in nature.

3. They have definite chemical and physical properties.

Which of the statements given above is/are correct?

1. 2 and 3 only
2. 1, 2 and 3
3. 1 and 2 only
4. 1 and 3 only

Answer (Detailed Solution Below)

Option 1 : 2 and 3 only

The Correct Answer is 2 and 3 only.

• Minerals in the Earth’s Crust
  • A mineral is a naturally occurring organic or inorganic substance, having an orderly atomic structure and a definite chemical composition and physical properties.
  • A mineral is composed of two or more elements. But, sometimes single element minerals like sulfur, copper, silver, gold, graphite, etc are also found.
  • The basic source of all minerals is the hot magma in the interior of the earth.
  • When magma cools, crystals of the minerals appear and a systematic series of minerals are formed in sequence to solidify to form rocks.
  • The crust of the earth is made up of more than 2000 minerals, but out of these, only six are the most abundant and contribute the maximum.
  • These six most abundant minerals are feldspar, quartz, pyroxenes, amphiboles, mica, and olivine.

• The three layers of the earth are as follows:
  • Crust: The uppermost layer over the earth’s surface is called the crust.
  • Mantle: Just beneath the crust is the mantle which extends up to a depth of 2900 km. below the crust.
  • Core: The innermost layer is the core with a radius of about 3500 km. It is mainly made up of nickel and iron and is called nifa.

• Rocks in the earth’s Crust
  • A rock is nothing but a composition of minerals.
  • They are aggregates or a physical mixture of one or more minerals.
  • Rocks may be hard or soft and in varied colours.
  • Feldspar and quartz are the most common minerals found in all types of rocks.
  • The science dealing with the study of rocks is called Petrology.

The _________ is responsible for Earth's magnetic field.

1. Mantle
2. Crust
3. Outer core
4. Inner core

Answer (Detailed Solution Below)

Option 3 : Outer core

The correct answer is outer core.

• 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.

• 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.

• 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.

How temperature varies towards the centre from the earth's surface?

1. Increases
2. Decreases
3. Remains same
4. None of these

Answer (Detailed Solution Below)

Option 1 : Increases

The correct answer is Increases

• 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.

​

India is divided into how many earthquake zones (seismic zones)?

1. 4
2. 2
3. 6
4. 5

Answer (Detailed Solution Below)

Option 1 : 4

The correct answer is 4.

• 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

Which is the second most abundant metal in the earth's crust?

1. Zinc
2. Iron
3. Aluminium
4. Copper

Answer (Detailed Solution Below)

Option 2 : Iron

The correct answer is Iron.

• Iron is the second most abundant metal in the earth's crust (5.0%).
• Aluminium is the most abundant metal found in the earth's crust (8.1%).
• Oxygen comprises of 46.6% of the total weight of the earth's crust.

Elements in earth's crust

Which of the following is an example of the most explosive type of volcano?

1. Shield volcanoes
2. Flood basalt volcanoes
3. Calderas volcanoes
4. Cinder cones volcanoes

Answer (Detailed Solution Below)

Option 3 : Calderas volcanoes

The correct answer is Calderas volcanoes.

• Calderas volcanoes are an example of the most explosive type of volcano.

• Caldera Volcanoes:
  • Calderas Volcanoes are known as the most explosive volcanoes on Earth.
  • When they erupt, they incline to drop on themselves rather than constructing any structure.
  • The fallen depressions are known as calderas.

•  Volcanoes:
  • A volcano is a vent or fissure in Earth’s crust through which lava, ash, rocks, and gases erupt.
• The other types of volcanoes are Shield Volcanoes and  Composite Volcanoes. 
• Shield volcanoes:
  • These are the largest of all the volcanoes on the earth.
  • These volcanoes are made up of basalt.
  • Eg: Hawaiian shield volcanoes.
• Flood Basalt volcanoes:
  • These volcanoes discharge highly fluid lava that flows for long distances.
  • Most parts of the world are covered by thick basalt lava flows.

The scale used for measuring the intensity of the earthquake is _____________.

1. Mercalli scale
2. Quake scale
3. Richter scale
4. Epicentre scale

Answer (Detailed Solution Below)

Option 1 : Mercalli scale

The correct answer is Mercalli scale.

• The intensity of an earthquake is measured by the Mercalli Scale.
• It is named after Mercalli, an Italian seismologist.
• It measures the energy released during the earthquake.
• The intensity scale takes into account the visible damage caused by the event.
• The range of intensity scale is from 1-12.

• Seismographs are instruments used to record seismic waves. Seismic waves are the vibrations from earthquake that travel through the Earth.
• There are four seismic zones (II, III, IV, and V) in India based on scientific inputs relating to seismicity.
• Previously, earthquake zones were divided into five zones with respect to the severity of the earthquakes but the Bureau of Indian Standards (BIS) grouped the country into four seismic zones by unifying the first two zones.
• BIS is the official agency for publishing seismic hazard maps and codes.
• Richter scale
  • The earthquake events are scaled either according to the magnitude or intensity of the shock.
  • The magnitude is expressed in absolute numbers, 0-10.
  • The power of an earthquake is expressed in terms of magnitude on a scale called the Richter scale.
  • It is also known as the Richter magnitude scale.
  • This was developed by Charles F. Richter in 1935.

• Mercalli scale is used to measure the intensity of an earthquake while Richter Scale is used to measure the magnitude scale of an earthquake.

What is the radius of earth?

1. 5999 kilometres 
2. 6371 kilometres 
3. 6990 kilometres 
4. 9066 kilometres 

Answer (Detailed Solution Below)

Option 2 : 6371 kilometres 

The correct answer is 6371 kilometres.

• 6,371 km is the radius of the earth.

• The interior of the earth can be divided into 3 different layers-
  • Crust 
  • Mantle
  • Core
• The crust is the outermost layer of the earth, and the core is the innermost layer of the earth, located at a depth of 2900 km.
• The distance to the centre of the Earth is 6,371 kilometres (3,958 mi), the crust is 35 kilometres (21 mi) thick, the mantle is 2855 km (1774 mi) thick.

______ is the most abundant element in Earth's crust.

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

Answer (Detailed Solution Below)

Option 3 : Oxygen

The correct answer is Oxygen.

• Oxygen is the most abundant element in Earth's crust.
• The name Oxygen comes from the Greek 'oxy genes', meaning acid-forming.
• Oxygen was discovered by Joseph Priestley in Wiltshire, England, and independently by Carl Wilhelm Scheele in Uppsala, Sweden.
• Oxygen is the chemical element with the symbol O and atomic number 8.

The innermost layer of the Earth is mainly made up of

1. Silica and Iron
2. Nickel and Alumina
3. Silica and Alumina
4. Nickel and Iron

Answer (Detailed Solution Below)

Option 4 : Nickel and Iron

The Earth is divided into four main layers: the solid crust on the outside, the mantle, the outer core, and the inner core.

The Core -

• The earthquake wave velocities helped in understanding the existence of the core of the earth.
• The core-mantle boundary is located at the depth of 2,900 km.
• The outer core is in a liquid state while the inner core is in the solid-state.
• The density of material at the mantle core boundary is around 5 g/cm3 and at the center of the earth at 6,300 km, the density value is around 13g/cm3.
• The core is made up of very heavy material mostly constituted by nickel and iron.
• It is sometimes referred to as the nife layer.

The correct answer is option 4, i.e Nickel and Iron.

The innermost layer of the earth is

1. Crust
2. Core
3. Mantle
4. Sima

Answer (Detailed Solution Below)

Option 2 : Core

The correct answer is Core.

• Earth Core:
  • The innermost layer of the earth is known as the core.
  • It is divided into the inner core and the outer core.
  • It comprises a high concentration of nickel and iron.
  • The outer core:
    • The outer core, surrounding the inner core, lies between 2900 km and 5100 km below the earth’s surface.
    • The outer core is composed of iron mixed with nickel (nife) and trace amounts of lighter elements.
  • The Inner Core:
    • The inner core extends from the center of the earth to 5100 km below the earth’s surface.
    • The inner core is generally believed to be composed primarily of iron (80%) and some nickel (nife).
    • Since this layer can transmit shear waves (transverse seismic waves), it is solid. (When P-waves strike the outer core inner core boundary, they give rise to S-waves)

• The mantle is the widest section of the Earth. Its thickness is approximately 2,900 km.
  • The mantle is mainly made up of semi-molten rock known as magma.
  • The rock is hard in the upper part of the mantle, but lower down the rock is softer and begins to melt. 
  • The mantle is located directly under the Sima
• The crust is the outer layer where we live.
  • The thickness is around 0-60 km.
  • It is a solid rock layer divided into two types:
    1. Continental crust covers the land
    2. Oceanic crust covers water
• Sima is an antiquated blended term for the lower layer of Earth's crust. This layer is made of rocks rich in magnesium silicate minerals.

The most abundant metal in the earth crust is

1. Sodium
2. Aluminium
3. Calcium
4. Iron

Answer (Detailed Solution Below)

Option 2 : Aluminium

Option 2 is correct, i.e. Aluminium.

• 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.

• 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.

The groundwater stored between layers of hard rock below the water table is called:

1. glacier 
2. geyser
3. hot spring
4. aquifer

Answer (Detailed Solution Below)

Option 4 : aquifer

The correct answer is aquifer.

• 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.

• 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 Pacific ring of fire' is associated with: 

1. Oil well Fires 
2. Thermal Power Station 
3. Volcanoes and Earthquakes
4. Forest Fires

Answer (Detailed Solution Below)

Option 3 : Volcanoes and Earthquakes

The correct answer is Volcanoes and Earthquakes.

Volcanoes and Earthquakes:

• The Ring of Fire is an area in the basin of the Pacific Ocean. Here a large number of earthquakes and volcanic eruptions occur.
• It covers about 40,000 km in a horseshoe shape.
• It has a continuous series of oceanic trenches, volcanic arcs, and volcanic belts, and plate movements.
• More than 75% of the world's active and dormant volcanoes are at this place.
• The Ring of Fire is a direct outcome of plate tectonics.

What is the approximate speed (in km/s) of the Earth in its orbit around the Sun?

1. 500
2. 10
3. 100
4. 30

Answer (Detailed Solution Below)

Option 4 : 30

The correct answer is 30.

• The interior structure of the Earth is made up of three main shells the very thin and brittle crust the mantle and the core.
• The earth s radius is 6,370 km.
• Earth is moving about our sun in a very nearly circular orbit. It covers this route at a speed of nearly 30 kilometres per second or 67,000 miles per hour.
• The circumference of a circle is equal to 2 x π x r. So in one year, Earth travels about 584 million miles.
• Earth travels about 1.6 million miles a day.

•  Structure of the Earth.

Almost 98% of Earth's crust is made up of eight elements. Which of the following does NOT figure among these elements?

1. Oxygen
2. Carbon
3. Silicon
4. Calcium

Answer (Detailed Solution Below)

Option 2 : Carbon

The correct answer is Carbon.

• The outermost surface of the Earth is called the lithosphere, or crust.
  • This rigid layer contains both the oceans and landmasses.
  • Most elements are found in only trace amounts within the earth’s crust, but several are abundant.
  • About 98% of the total crust is made up of eight elements as oxygen, silicon, aluminum, iron, calcium, sodium, potassium, and magnesium.
  • The rest 2% is constituted by elements like titanium, hydrogen, phosphorous, manganese, sulphur, carbon, nickel, and others.
  • The elements in the earth’s crust are rarely found exclusive but are usually combined with other elements to make various substances.
  • Oxygen is by far the most abundant element in earth's crust at 46.6 percent, nearly half of the mass of the crust.

Barren island, the only active volcano in India is located in:

1. Ritchie’s Archipelago
2. Andaman & Nicobar Islands
3. Lakshadweep Islands
4. Labyrinth Island

Answer (Detailed Solution Below)

Option 2 : Andaman & Nicobar Islands

The correct answer is Andaman&Nicobar Island.

• The only active volcano of India is situated in the Barren Island volcano of the Andaman and Nicobar Islands.
• It is composed of ash and spewing lava. A team of scientists from the National Institute of Oceanography (NIO) Goa identified this and had done an expedition on this. The volcano was erupting in small episodes lasting around 5-10 minutes.

• Barren Island has located about 140 km from Port Blair. It is surrounded by waters which is ideal for scuba diving and is home to a wide variety of aquatic life. 
• It’s the only active volcano in India along a chain of volcanoes from Sumatra (Indonesia) to Myanmar.
• The current Lieutenant Governor of Andaman&Nicobar Island is Mr. Admiral D K Joshi.

The boundary between the crust and mantle is called as:

1. Lithosphere
2. Benioff zone
3. Bedrock
4. Moho

Answer (Detailed Solution Below)

Option 4 : Moho

Explanation:

Lithosphere: Lithosphere, rigid, rocky outer layer of the Earth, consisting of the crust and the solid outermost layer of the upper mantle. It extends to a depth of about 100 km.

Benioff zone: A dipping planar (flat) zone of earthquakes that is produced by the interaction of a downgoing oceanic crustal plate with a continental plate.

Bedrock: The hard area of rock in the ground that holds up the loose soil above.

Moho: The Moho is the boundary between the crust and the mantle in the earth. This is a depth where seismic waves change velocity and there is also a change in chemical composition. Also termed the Mohorovicic discontinuity.

1° latitude is equal to approximately ______ km.

1. 111
2. 122
3. 145
4. 133

Answer (Detailed Solution Below)

Option 1 : 111

The correct answer is 111.

• Each latitude on earth is equal to almost 111 kilometers.
• This distance decreases marginally as one travels to poles and increases marginally as one goes towards the equator.

• Latitude
  • Imaginary lines running east-west.
• Longitude
  • The vertical lines running north-south, join the two poles. 
• The earth is totally taken to be at 360°. Therefore it has 360 meridians. 1 meridian = 1°.
• 1° longitude = 4 Minutes.
• 180° longitude = 180 × 4 = 720 minutes = 12 hrs
• The Prime Meridian (0°) runs through the Greenwich Observatory in England, the location agreed upon by a conference in 1884.
• On the opposite side of the Earth is the international dateline at approximately 180° longitude.

Which zone separates the crust and mantle?

1. Stratosphere
2. Moho
3. Lithosphere
4. Asthenosphere

Answer (Detailed Solution Below)

Option 2 : Moho

The correct answer is Moho.

• The boundary between the crust and the asthenosphere (upper reaches of the mantle) where there is a discontinuity in the seismic velocity forms the Mohorovicic (Moho) discontinuity.
• It occurs at an average depth of approximately eight kilometers below the ocean basin and 30 kilometers below the continental surface. 
• A change in rock composition from rocks containing feldspar (above) to rocks containing no feldspar (below) is thought to be the cause of the Moho.
• Mohorovicic Discontinuity (Moho) separates the mantle from the crust.
• Asthenosphere is the highly viscous part of the mantle, mechanically weak and ductile.
• Seismic discontinuities are the regions of the earth where, due to a marked change in physical or chemical properties, seismic waves act much differently compared to the surrounding regions.
• Gutenberg Discontinuity: the mantle and the outer core lie between them.

Mohorovicic (Moho) discontinuity

Which island among the following has an active Volcano?

1. Lakshadweep
2. Andaman Islands
3. Diu
4. Daman

Answer (Detailed Solution Below)

Option 2 : Andaman Islands

The correct answer is option 2 i.e Andaman Islands.

The Andaman Islands have an active volcano i.e Barren Islands.

Difference between Active, Dormant, and Extinct Volcanoes is listed below:

What three parts can the earth be divided into?

Why do we divide the earth into four spheres?

What are the 4 subsystem of the earth?

How are the four spheres of the Earth connected?