The Earth (Latitude, Longitude, Time Zones, Solstices and Equinoxes)

Q1. Point of intersection of the Equator and the Prime Meridian is located at- U.P. Lower Sub. (Pre) 2009

(a) Atlantic Ocean

(b) Ghana

(d) Pacific Ocean

Ans. (a)

The Equator (0° latitude) and the Prime Meridian (0° longitude) intersect in the Gulf of Guinea, Atlantic Ocean, making Atlantic Ocean the correct answer.

Q2. The country which has the longest north-south (latitudinal) extension of its territory is- 65th B.P.S.C. (Pre) 2019

(a) Russia

(b) Chile

(d) Brazil

(e) None of the above/More than one of the above

Ans. (e)

Explanation:

Chile has the longest continuous mainland north-south extent, while Russia has a greater total latitudinal extent when its islands are included.
Therefore, more than one country satisfies the condition, making option (e) the correct answer.

Q3. How many latitudes are there on the globe drawn at 1 degree interval? 69th B.P.S.C. (Pre), 2023

(a) 180

(b) 178

(d) None of the above

Ans. (c)

Explanation:

If parallels of latitude are drawn at an interval of one degree, there will be 89 parallels in the Northern Hemisphere and 89 parallels in the Southern Hemisphere.
Including the Equator, the total number of latitudes drawn will be 179, making option (c) 179 the correct answer.

Q4. The time at Cairo is 2 hours ahead of Greenwich. Hence, it is located at- 53rd to 55th B.P.S.C. (Pre) 2011

(a) 30° W longitude

(b) 30° E longitude

(d) 28° W longitude

Ans. (b)

Explanation:

Cairo (Egypt) is located at approximately 30° E longitude, and its time is 2 hours ahead of Greenwich Mean Time (GMT).
Since the Earth rotates 360° in 24 hours, it covers 1° longitude in 4 minutes. Therefore, a difference of 120 minutes (2 hours) corresponds to 30° longitude, making option (b) 30° E longitude the correct answer.

Q5. In the New Millennium, the first ray of the Sun was seen in which of the following Meridians of India- U.P.P.C.S. (Pre) 2001

(a) 20° 30'W

(b) 82° 30'E

(d) 93° 30'E

Ans. (d)

Explanation:

According to the Royal Greenwich Laboratory’s declaration, the first ray of sunrise in India on the occasion of the New Millennium was seen on Katchal Island near the Andaman and Nicobar Islands.
Katchal Island is situated approximately 1600 km away from mainland India and about 418 km from Port Blair.
It lies near 7°56' North latitude and 93°24' East longitude, which is closest to 93°30'E Meridian.
Therefore, option (d) 93°30'E is the correct answer.

Q6. The basis of deciding the standard time of any place is- 43rd B.P.S.C. (Pre) 1999

(a) Longitude

(b) Latitude

(d) Prime Meridian

Ans. (d)

Explanation:

The Prime Meridian is also called the Greenwich Meridian or International Meridian and is located at 0° longitude.
The standard time of different places is calculated with reference to this meridian, which passes through the Royal Greenwich Observatory in England.
The International Date Line is located at approximately 180° longitude and is used for determining the change of date, not standard time.
The Prime Meridian passes through countries including the United Kingdom, France, Spain, Algeria, Mali, Burkina Faso, Togo, and Ghana. Therefore, option (d) Prime Meridian is the correct answer.

Q7. The standard time of the following countries is ahead of or behind Greenwich Mean Time depending on whether they are East or West of the longitude passing through Greenwich.

(1) Cuba

(2) Greece

(3) Iraq

(4) Costa Rica

(5) Japan.

Which one of the following sequential orders gives the correct arrangement of the countries according to their standard time from ahead to behind GMT? I.A.S. (Pre) 1995

(a) 5, 3, 2, 1, 4

(b) 2, 4, 1, 3, 5

(d) 3, 5, 4, 1, 2

Ans. (a)

Explanation:

The Greenwich Meridian (0° longitude), passing through England, is used as the reference line for calculating Greenwich Mean Time (GMT).
Countries located in the Eastern Hemisphere have time ahead of GMT, while countries in the Western Hemisphere have time behind GMT.
The standard times of the given countries are:
Japan = GMT +9 hours
Iraq = GMT +3 hours
Greece = GMT +2 hours
Cuba = GMT –5 hours
Costa Rica = GMT –6 hours
Therefore, the correct order from ahead of GMT to behind GMT is Japan, Iraq, Greece, Cuba, and Costa Rica (5, 3, 2, 1, 4), making option (a) the correct answer.

Q8. Which one of the following Straits is nearest to the International Date Line? I.A.S. (Pre) 2008

(a) Malacca Strait

(b) Bering Strait

(d) Strait of Gibraltar

Ans. (b)

Explanation:

The International Date Line is located near the 180° meridian, which lies opposite the Prime Meridian (0° longitude) on the globe.
A place located closest to the 180° longitude will be nearest to the International Date Line.
The approximate longitudes of the given straits are:
Malacca Strait – 99°32'E
Bering Strait – 168°23'W
Strait of Florida – 82°23'W
Strait of Gibraltar – 5°41'W
Since the Bering Strait (168°23'W) lies closest to the 180° meridian, it is nearest to the International Date Line. Therefore, option (b) Bering Strait is the correct answer.

Q9. Consider the following statements: I.A.S. (Pre) 2025

I. Anadyr in Siberia and Nome in Alaska are a few kilometers from each other, but when people are waking up and getting set for breakfast in these cities, it would be different days.

II. When it is Monday in Anadyr, it is Tuesday in Nome.

Which of the statements given above is/are correct?

(a) I only

(b) II only

(d) Neither I nor II

Ans. (a)

Explanation:

Anadyr is in Siberia and is about UTC+12, while Nome follows Alaska Time, which is substantially behind Anadyr.
Their locations on opposite sides of the International Date Line can result in different calendar dates at comparable local morning times.
When it is Monday in Anadyr, it is Sunday in Nome, not Tuesday.
Therefore, Statement I is correct and Statement II is incorrect. Hence, option (a) is correct.

Q10. What is the local time of Thimphu (Bhutan) located at 90° East longitude when the time at Greenwich (0°) is 12:00 noon- 69th B.P.S.C. (Pre), 2023

(a) 6:00 p.m.

(b) 4:00 p.m.

(d) 6:00 a.m.

Ans. (a)

Explanation:

The longitudinal difference between Greenwich (0°) and Thimphu, Bhutan (90°E) is 90°.
The Earth rotates 1° longitude in 4 minutes, so the time difference for 90° longitude is:
90 × 4 = 360 minutes = 6 hours.
Since Thimphu is located to the east of Greenwich, its local time will be 6 hours ahead of Greenwich Mean Time.
Therefore, when the time at Greenwich is 12:00 noon, the local time at Thimphu will be 6:00 p.m., making option (a) the correct answer.

Q11. Consider the following countries: I.A.S. (Pre) 2025

I. United Kingdom

II. Denmark

III. New Zealand

IV. Australia

V. Brazil.

How many of the above countries have more than four time zones?

(a) All the five

(b) Only four

(d) Only two

Ans. (b)

Explanation:

The number of time zones varies when a country’s overseas territories and dependent regions are also considered.
The time zones of the given countries are:
United Kingdom – 9 time zones
Denmark (including Greenland and Faroe Islands) – 6 time zones
New Zealand (including associated territories) – 5 time zones
Australia (including dependent territories) – 9 time zones
Brazil – 4 time zones
Therefore, the countries having more than four time zones are United Kingdom, Denmark, New Zealand, and Australia.
Hence, four countries satisfy the condition, making option (b) Only four the correct answer.

Q12. Through which, one of the following groups of countries does the Equator pass? I.A.S. (Pre) 2006

(a) Brazil, Zambia and Malaysia

(b) Colombia, Kenya and Indonesia

(d) Venezuela, Ethiopia and Indonesia

Ans. (b)

Explanation:

The Equator (0° latitude) passes through a total of 13 countries across South America, Africa, and Asia.
The countries through which the Equator passes include Brazil, Colombia, Democratic Republic of the Congo, Ecuador, Gabon, Indonesia, Kenya, Kiribati, Republic of the Congo, Sao Tome and Principe, Somalia, Uganda, and Maldives.
Among the given options, Colombia, Kenya, and Indonesia are all located on the Equator.
Therefore, option (b) Colombia, Kenya and Indonesia is the correct answer.

Q13. Which one of the following cities is nearest to the Equator? I.A.S. (Pre) 2008

(a) Colombo

(b) Jakarta

(d) Singapore

Ans. (d)

Explanation:

The distance of a place from the Equator is determined by its latitude; the smaller the latitude value, the closer the place is to the Equator (0° latitude).
The approximate latitudes of the given cities are:
Colombo – 6°55'30"N
Jakarta – 6°12'S
Manila – 14°35'30"N
Singapore – 1°21'N
Since Singapore lies at the lowest latitude among the given cities, it is the closest to the Equator. It is located approximately 137 km from the Equator.
Therefore, option (d) Singapore is the correct answer.

Q14. At the Winter Solstice the noon altitude of the Sun at the Tropic of Cancer is- U.P.P.C.S. (Pre) 1997

(a) 23.5°

(b) 43.0°

(d) 66.5°

Ans. (b)

Explanation:

The Winter Solstice occurs around 22 December, when the Sun’s rays fall vertically on the Tropic of Capricorn (23.5°S).
At this time, the Sun’s altitude at the Tropic of Capricorn is 90°, while the Tropic of Cancer is located at a distance of 47° latitude from it.
The difference between the two Tropics is:
23.5° + 23.5° = 47°.
Therefore, the noon altitude of the Sun at the Tropic of Cancer will be:
90° – 47° = 43°, making option (b) 43.0° the correct answer.

Q15. The Tropic of Cancer does not pass through- U.P.P.C.S. (Pre) 2005

(a) Egypt

(b) India

(d) Myanmar

Ans. (c)

Explanation:

The Tropic of Cancer (23.5°N latitude) passes through several countries of Asia, Africa, and North America, including India, Myanmar, Egypt, China, Saudi Arabia, and Mexico.
The countries/regions through which the Tropic of Cancer passes include Mexico, The Bahamas, Mauritania, Mali, Algeria, Niger, Libya, Egypt, Saudi Arabia, UAE, Oman, India, Bangladesh, Myanmar, China, Taiwan, and Western Sahara.
Among the given options, Iran is not crossed by the Tropic of Cancer.
Therefore, option (c) Iran is the correct answer.

Q16. Tropic of Capricorn does not pass through- U.P. Lower Sub. (Pre) 1997

(a) Bolivia

(b) Paraguay

(d) Brazil

Ans. (a)

Explanation:

The Tropic of Capricorn (23.5°S latitude) passes through countries located in South America, Africa, and Oceania.
The countries/regions through which the Tropic of Capricorn passes include Brazil, Paraguay, Argentina, Chile, South Africa, Botswana, Namibia, Mozambique, Madagascar, Australia, Tonga, and French Polynesia (France).
Among the given options, Bolivia is not crossed by the Tropic of Capricorn.
Therefore, option (a) Bolivia is the correct answer.

Q17. In the northern hemisphere, the longest day of the year normally occurs in the- I.A.S. (Pre) 2022

(a) First half of the month of June

(b) Second half of the month of June

(d) Second half of the month of July

Ans. (b)

Explanation:

In the Northern Hemisphere, the longest day of the year occurs during the Summer Solstice, which generally falls on 20 or 21 June.
Since this date falls in the second half of June, the duration of daylight is maximum in this period.
In contrast, the Southern Hemisphere experiences its longest day during the second half of December due to the opposite seasonal cycle.
Therefore, option (b) Second half of the month of June is the correct answer.

Q18. The shortest day of the year in Northern Hemisphere is on- 47th B.P.S.C. (Pre) 2005, M.P.P.C.S. (Pre) 1990

(a) 21 December

(b) 22 December

(d) 22 June

Ans. (b)

Explanation:

The shortest day in the Northern Hemisphere occurs during the Winter Solstice, which generally falls on 21 or 22 December.
On this day, the Sun’s rays fall vertically on the Tropic of Capricorn, resulting in minimum daylight duration in the Northern Hemisphere.
In contrast, the longest day in the Northern Hemisphere occurs during the Summer Solstice on 20 or 21 June.
Therefore, option (b) 22 December is the correct answer.

Q19. On which of the following dates your shadow at noon is the smallest? U.P.P.C.S. (Pre) 2006

(a) December 25

(b) March 21

(d) February 14

Ans. (c)

Explanation:

The length of a shadow at noon depends on the altitude of the Sun; the higher the Sun appears in the sky, the shorter the shadow.
Due to the Earth's revolution around the Sun and the inclination of its axis, the apparent position of the Sun shifts northward and southward during the year.
Around 21 June (Summer Solstice), the Sun is directly overhead at the Tropic of Cancer (about 23.5°N) at noon.
Therefore, at the Tropic of Cancer, the noon shadow is nearly zero on this date, making June 21 the intended answer. Hence, option (c) is correct.

Q20. On 21st June, the Sun- I.A.S. (Pre) 2019

(a) does not set below the horizon at the Arctic Circle

(b) does not set below the horizon at Antarctic Circle

(d) shines vertically overhead at the Tropic of Capricorn

Ans. (a)

Explanation:

On 21st June, the Northern Hemisphere experiences the Summer Solstice, when the Sun’s rays fall vertically on the Tropic of Cancer (23.5°N).
On this day, the Arctic Circle experiences continuous daylight, and the Sun does not set below the horizon due to the Earth’s axial tilt.
The Sun is directly overhead at the Equator only during the Equinoxes, not on 21st June.
Therefore, option (a) does not set below the horizon at the Arctic Circle is the correct answer.

Q21. On June 21 every year, which of the following latitude(s) experience(s) a sunlight of more than 12 hours? I.A.S. (Pre) 2024

Equator
Tropic of Cancer
Tropic of Capricorn
Arctic Circle

Select the correct answer using the code given below:

(a) 1 only

(b) 2 only

(d) 2 and 4

Ans. (d)

Explanation:

On 21st June, the Northern Hemisphere is tilted towards the Sun, causing the Summer Solstice. During this time, places in the Northern Hemisphere receive sunlight for more than 12 hours.
The Tropic of Cancer receives direct rays of the Sun, while areas near and beyond the Arctic Circle experience very long days, with regions near the North Pole receiving continuous daylight.
The Equator receives nearly equal day and night throughout the year, while the Tropic of Capricorn in the Southern Hemisphere experiences shorter days during this period.
Therefore, the latitudes experiencing more than 12 hours of sunlight are Tropic of Cancer and Arctic Circle, making option (d) 2 and 4 the correct answer.

Q22. Consider the following statements: I.A.S. (Pre) 2025

Statement I: Scientific studies suggest that a shift is taking place in the Earth's rotation and axis.

Statement II: Solar flares and associated coronal mass ejections bombarded the Earth's outermost atmosphere with tremendous amount of energy.

Statement III: As the Earth's polar ice melts, the water tends to move towards the equator. Which one of the following is correct in respect of the above statements?

(a) Both Statement II and Statement III are correct and both of them explain Statement I.

(b) Both Statement II and Statement III are correct but only one of them explains Statement I.

(d) Neither Statement II nor Statement III is correct.

Ans. (b)

Explanation:

Scientific observations show that the Earth’s rotational axis has undergone slight shifts over time, and the length of the day has also changed by a very small but measurable amount. Therefore, Statement I is correct.
Solar flares and coronal mass ejections (CMEs) release huge amounts of energy that interact with the Earth’s outer atmosphere and magnetosphere. Hence, Statement II is factually correct, but it does not significantly influence the Earth’s rotation or axis shift.
The melting of polar ice sheets causes a redistribution of Earth’s mass, as meltwater moves into oceans and spreads towards lower latitudes, including the equatorial region. Therefore, Statement III is correct and explains changes in the Earth’s rotation and axis.
Thus, both Statement II and Statement III are correct, but only Statement III explains Statement I, making option (b) the correct answer.

Origin of the Earth, The Geological History

Q1. Which of the following scholar has suggested that the Earth has originated from the gases and the dust particles? I.A.S. (Pre) 1999

(a) James Jeans

(b) H. Alfven

(d) O. Schmidt

Ans. (d)

Explanation:

Otto Schmidt suggested the gas and dust hypothesis (Interstellar dust hypothesis) for the formation of the Earth.
According to this hypothesis, large quantities of gas and dust particles captured by the Sun’s gravitational force combined together and formed the Earth.
James Jeans and Harold Jeffreys are associated with the tidal hypothesis related to the origin of the Earth.
F. Hoyle and Littleton proposed the Nova hypothesis for the origin of the Earth.
Hence, option d is correct.

Q2. Which of the following periods has generally been considered to be the 'Little Ice Age'? U.P.P.C.S. (Pre) (Re-Exam) 2015

(a) 750 A.D. - 850 A.D.

(b) 950 A.D. - 1250 A.D.

(d) 8000 to 10,000 years B.P. (Before Present)

Ans. (c)

Explanation:

The Little Ice Age refers to a period of significant cooling, generally considered from about 1300 A.D. to 1870 A.D.
During this period, Europe and North America experienced much colder winters compared to those of the 20th century.
Among the given options, 1650 A.D. - 1870 A.D. represents the later phase of the Little Ice Age and is the correct option.
Hence, option c is correct.

Q3. Continents have drifted apart because of- 53rd to 55th B.P.S.C. (Pre) 2011

(a) Volcanic eruptions

(b) Tectonic activities

(d) All of the above

Ans. (b)

Explanation:

Continents are situated on huge slabs of rocks known as tectonic plates.
These plates are continuously moving and interacting through the process of plate tectonic activity.
The movement of tectonic plates causes the shifting of continents over the Earth’s lithosphere.
Hence, option b is correct.

Q4. The southern continent broken from Pangaea is called: 68th B.P.S.C. (Pre) 2022

(a) Pacific Ocean

(b) Laurasia

(d) More than one of the above

(e) None of the above

Ans. (c)

Explanation:

Pangaea was a supercontinent that later split into two major landmasses: Laurasia in the north and Gondwanaland in the south.
Gondwanaland included most of the present-day landmasses such as Antarctica, South America, Africa, Madagascar, Australia, the Arabian Peninsula, and Peninsular India.
Hence, option c is correct.

Q5. Cocos Plate lies between: 63rd B.P.C.S. (Pre) 2017

(a) Central America and Pacific Plate

(b) South America and Pacific Plate

(d) Asiatic Plate and Pacific Plate

(e) None of the above / More than one of the above

Ans. (a)

Explanation:

The Cocos Plate is a tectonic plate located between Central America and the Pacific Plate.
It is an oceanic plate that plays an important role in the tectonic activity of the eastern Pacific region.
Hence, option a is correct.

Q6. Which of the following phenomena might have influenced the evolution of organisms? I.A.S. (Pre) 2014

Continental drift
Glacial cycles

Select the correct answer using the code given below.

(a) 1 only

(b) 2 only

(d) Neither 1 nor 2

Ans. (c)

Explanation:

Continental drift influenced the evolution of organisms by separating landmasses and creating geographical isolation, which led to the development of new species.
Glacial cycles affected climate conditions, habitats, and the distribution of organisms, thereby influencing their evolutionary processes.
Therefore, both continental drift and glacial cycles have played roles in shaping the evolution of organisms.
Hence, option c is correct.

Q7. The theory that states "pieces of the Earth's crust are in constant, slow motion driven by movement in the mantle" is called: 69th B.P.S.C. (Pre), 2023

(a) the theory of continental drift

(b) the theory of Pangaea

(d) the theory of plate boundaries

Ans. (c)

Explanation:

The theory of plate tectonics explains that the Earth's lithosphere is divided into several rigid plates that move slowly over the underlying, relatively plastic asthenosphere. Their movement is driven by processes associated with Earth's internal heat, including mantle convection and other plate-driving forces.
These plates consist of oceanic and/or continental lithosphere and interact along plate boundaries through processes such as divergence, convergence and transform movement.
Plate tectonics provides the modern framework for explaining continental movement, seafloor spreading, mountain building, earthquakes and volcanism.
The major plates commonly identified include the Pacific, North American, South American, African, Eurasian, Antarctic and Indo-Australian plates.
Hence, option (c) Plate Tectonics is the correct answer.

Q8. Which of the following are the evidence of the phenomenon of continental drift? I.A.S. (Pre) 2025

I. The belt of ancient rocks from Brazil coast matches with those from Western Africa.

II. The gold deposits of Ghana are derived from the Brazil plateau when the two continents lay side by side.

III. The Gondwana system of sediments from India is known to have its counterparts in six different landmasses of the Southern Hemisphere.

Select the correct answer using the code given below.

(a) I and III only

(b) I and II only

(d) II and III only

Ans. (c)

The eastern coast of Brazil and the coastal belt of West Africa contain similar ancient rocks of about 2,000 million years old, as revealed by radiometric dating, indicating that these regions were once connected. Hence, statement I is correct.
The similarity between Ghana’s gold deposits and the source rocks of the Brazilian Plateau suggests that Africa and South America were joined together before their separation. Hence, statement II is correct.
The Gondwana system of sediments found in India has similar counterparts in six other landmasses of the Southern Hemisphere with comparable thickness, composition, and sequence, indicating their common origin. Hence, statement III is correct.
Therefore, all three statements (I, II and III) are correct, and the correct option is (c).

Q9. The process that continually adds new crust is: 69th B.P.S.C. (Pre), 2023

(a) subduction

(b) earthquake

(d) convection

Ans. (c)

Explanation:

Seafloor spreading is the process through which new crust is continuously formed at mid-oceanic ridges due to the upward movement of magma and its solidification. Hence, seafloor spreading is the correct process that adds new crust.
Subduction is the process in which old oceanic crust is destroyed by sinking into the mantle at convergent plate boundaries. Hence, subduction does not add new crust.
The processes of seafloor spreading and subduction approximately balance each other, maintaining the Earth’s shape and diameter. Hence, both processes are important aspects of plate tectonics.
Therefore, the correct option is (c) seafloor spreading.

Q10. Folding is the result of- 53rd to 55th B.P.S.C. (Pre) 2011

(a) Epeirogenic force

(b) Coriolis force

(d) Exogenic force

Ans. (c)

Explanation:

Orogenic forces are mountain-building forces that act over millions of years and cause the formation of mountains from plains and seabeds. Hence, folding is the result of orogenic force.
These forces are generated due to the interaction of tectonic plates, which compress and uplift rock layers to form mountain ranges. Hence, orogenic forces are responsible for crustal folding.
Therefore, the correct option is (c) Orogenic force.

Q11. Consider the following: I.A.S. (Pre) 2013

Electromagnetic radiation
Geothermal energy
Gravitational force
Plate Movements
Rotation of Earth
Revolution of the Earth

Which of the following above are responsible for bringing dynamic changes on the surface of the Earth?

(a) 1,2,3 and 4

(b) 1,3,5 and 6

(d) 1,2,3,4,5 and 6

Ans. (d)

Explanation:

Electromagnetic Radiation: Solar radiation heats the Earth's surface and drives processes such as evaporation, precipitation and weathering, contributing to changes on the Earth's surface.
Geothermal Energy: Heat from within the Earth drives endogenic processes such as diastrophism and volcanism, which modify the Earth's crust.
Gravitational Force: Gravity acts as a downslope force, causing processes such as mass movement, landslides and avalanches.
Plate Movements: Movement of lithospheric plates causes major tectonic processes such as continental movement, mountain building and earthquakes.
Rotation of the Earth: Earth's rotation influences atmospheric circulation, winds and ocean currents, which in turn affect surface processes.
Revolution of the Earth: Earth's revolution around the Sun, together with the Earth's axial tilt, produces seasonal variations, influencing climate, precipitation and related geomorphic processes.

Hence, all six factors contribute, directly or indirectly, to dynamic changes on the Earth's surface. Therefore, the correct answer is (d) 1, 2, 3, 4, 5 and 6.

Q12. Arrange in chronological order: U.P. P.C.S. (Mains) 2017

Patpara formation
Khetaunhi formation
Baghor formation
Sihawal formation

Codes:

(a) 1, 4, 2, 3

(b) 4, 1, 3, 2

(d) 4, 3, 2, 1

Ans. (b)

Explanation:

Sihawal Formation: It belongs to the Lower Palaeolithic period and represents the earliest phase among the given formations. Hence, Sihawal formation is placed first in chronological order.
Patpara Formation: It is associated with the Middle Palaeolithic period and developed after the Sihawal formation. Hence, Patpara formation is placed second.
Baghor Formation: It belongs to the Upper Palaeolithic period and represents a later stage of human cultural development. Hence, Baghor formation is placed third.
Khetaunhi Formation: It is associated with the Neolithic and Microlithic ages, representing the latest phase among the given formations. Hence, Khetaunhi formation is placed fourth.
Therefore, the correct chronological order is Sihawal → Patpara → Baghor → Khetaunhi, and the correct option is (b) 4, 1, 3, 2.

Q13. Rajasthan desert or Thar desert is the expanse of which of the following? U.P. P.C.S. (Pre) 2018

(a) Pilocene

(b) Paleocene

(d) Oligocene

Ans. (c)

Explanation:

The Rajasthan Desert or Thar Desert is mainly formed by Pleistocene and recent deposits. Hence, option (c) is correct.
The Thar Desert is a rainfall-deficient region, and according to the Department of Archaeology, its formation began approximately 70,000 years ago. Hence, its development is associated with recent geological deposits.
The Pleistocene epoch extended from about 2 million years ago to 10,000 years ago. Hence, Pleistocene deposits are linked with the formation of the Thar Desert.
Therefore, the correct option is (c) Pleistocene and recent deposits.