Answered: Mains Marathon – UPSC Mains Current Affairs Questions – March 30

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Following are the Suggested Answers for Mains Marathon, March 30:

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1.List some differences between chemical and physical weathering. Describe the significance of weathering.(GS 1)

रासायनिक और शारीरिक मौसम के बीच में अंतरों की सूची लिखें। इसके महत्वों का वर्णन करें।

Link-1 | Link-2 | Link-3

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Weathering:

• It is the total effect of the various sub aerial processes that cooperate in bringing about decay and disintegration of rock involving no large scale transportation.
• Weathering is generally divided into three types:
  • Physical weathering
  • Chemical weathering
  • Biological weathering

Importance of weathering:

• Provides raw material in the form of regolith for the development of soil.The depth of the soil therefore depend on the extent to which rock have been weathered.
• Weathering produces other natural resources such asclay which is used for making bricks.
• Weathering breaks rocks into their mineral components.It also creates new compounds through chemical changes.
  • During the prolonged period of time, the weathering processes produce concentrations of valuable mineral ores of iron, manganese, tin, aluminium, and uranium etc.
• Weathering weakens rocksmaking them easier people to exploit for example by mining and quarrying.
• Also weathering is significant since it prepares the land on which the agents of erosion and transportation act on.These agents then modify the original landforms .
• Some weathered rock like the granitic tors are very fascinating.  They therefore act astourist attraction.
  • Example includes the Bismarck rock in Mwanza Tanzania.
  • They have turned them into into local shrineswhere they make offerings.
  • Prepares earth materials for transport by surficial processes
  • It is very important for supporting ecosystems and life.

Differences:

1.Definitions:

• Physical weathering  is the physical breakdown of rock masses under the attack of certain atmospheric agents.
• chemical decomposition of the rock is called chemical weathering which is nothing but chemical reaction between gases of the atmosphere and minerals of the rocks.

2.Effect on different areas:-

• Chemical activity dominant in high temperature and high rainfall.
• Physical weathering is the most active in cold, dry and higher areas of the earth surface Temperature variations are responsible to a great extent of physical weathering.

3.Composition of rocks:-

• Physical weatheringdescribes a change that affects the structure of a rock, but not its composition
• chemical weatheringalters the chemicals that compose the rocks.

4.Types:

• Abrasion, thermal expansion, exfoliation are the processes of physical weathering
• Oxidation, hydrolysis, carbonation are some of the processes of chemical weathering

5.Causing factors:

• changes in temperature and pressure surrounding rocks. The expansion or contraction of air and pressure creates fractures in rock surfaces, ultimately making rocks break into smaller pieces.
• Substances capable of causing chemical weathering include water and acids.

Despite the differences both the types work hand in hand.

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2.How does plate tectonics theory explain the formation of the Himalayas and Deccan Traps? Briefly explain. (GS 1)

प्लेट टेक्टोनिक्स सिद्धांत हिमालय और दक्कन जाल की गठन कैसे करते हैं? संक्षिप्त व्याख्या लिखें।

Link

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Background:

• From the deepest ocean trench to the tallest mountain, plate tectonics explains the features and movement of Earth’s surface in the present and the past.
• Plate Tectonic theory is based on sea floor spreading theory and Paleo
• It states that Lithosphere is not continuous but broken into plates which float on asthenosphere. The Movement of these plates is responsible for formation of various landforms on earth.

Himalayas:

• The Himalayan formation is the witness of how plate tectonics can play massive role on earth .
• The Himalayan mountain range and Tibetan plateau have formed as a result of the collision between the Indian Plate and Eurasian Plate which began 50 million years ago and continues today.
• The supercontinent Pangea began to break up 200 Million years ago and India started a northward drift towards Asia.
• 80 million years ago at this time Tethys Ocean floor would have been subducting northwards beneath Asia and the plate margin would have been a Convergent oceanic-continental one.
• However not all of the Tethys Ocean floor was completely subducted.Most of the thick sediments on the Indian margin of the ocean were scraped off and accreted onto the Eurasian continent in what is known as an accretionary wedge. These scraped-off sediments are what now form the Himalayan mountain range.
• From about 50-40 Ma the rate of northward drift of the Indian continental plate slowed to around 4-6 cm per year. This slowdown is interpreted to mark the beginning of the collision between the Eurasian and Indian continental plates, the closing of the former Tethys Ocean, and the initiation of Himalayan uplift.
• The Eurasian plate was partly crumpled and buckled up above the Indian plate but due to their low density/high buoyancy neither continental plate could be subducted. This caused the continental crust to thicken due to folding and faulting by compressional forces pushing up the Himalaya and the Tibetan Plateau.
• The continental crust here is twice the average thickness at around 75 km. The thickening of the continental crust marked the end of volcanic activity in the region as any magma moving upwards would solidify before it could reach the surface.

Deccan traps:

• The Deccan Traps are one of the largest volcanic provinces in the world.
• It occurred due to sea floor spreading between Indian and African Plates which pushed the Indian plate northwards  towards the Eurasian plate.
• While this happened the Indian plate crossed the reunion island basically a hot spot.Deccan Trap volcanism is associated with this deep mantle plume or hot spot.
• The plume or hot spot caused the continent to break apart and  lead to a layer deposition of the volcanic matter in the layered structure, this lead to the formation of deccan trap.

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3.What do you understand by integrity? What are the difficulties in practicing it in public life? (GS 4)

आप ईमानदारी से क्या समझते हैं? सार्वजनिक जीवन में इसको अभ्यास करने में क्या मुश्किलें हैं?

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Integrity:-

• An individual is said to possess the virtue of integrity if the individual’s actions are based upon an internally consistent framework of principles.
• Ethics is about following the rules, and integrity is about doing the right thing, regardless of the rules
• If you’re a person of integrity, you’ll not do the duties your conscience doesn’t agree with.
  • Example:
    • Policeman ordered to fire on unarmed peaceful protestors. Honest policeman will obey the order. Policeman of integrity, will refuse to fire.

Difficulties faced by people when they practise integrity in public life are:–

• When a person has integrity it gets difficult to maintain relationshipsand some personal losses might happen  as the person might be true to his/her intrinsic values.
• Ethical dilemma:-
  • When a civil servant according to law  is asked to forcefully push the protesters away ,a person with integrity might not be able to do it if he/she finds justice in the protest.
• Extreme pressure:
  • For a person who is acting with integrity an extreme pressure from multiple avenues could impact him adversely.
• A person with integrity need not always be an efficient administrator as his/her actions might delay decisions when all multiple aspects are looked into.

Despite difficulties ,a person with integrity is always respected by the society and one always strive to have integrity as it leads to a happy life.

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