Q30. Which process is characteristic of the formation of sedimentary rocks?
[SSC CGL Tier-I (7 December 2022, Shift 4)]
- (A) Lineation
- (B) Banded texture
- (C) Foliation
- (D) Lithification
Answer: (D) Lithification
Explanation: Lithification converts loose sediment into coherent rock through compaction and cementation. Such processes formed many sandstone and shale beds in Indian basins. Foliation and strong banding are instead often associated with metamorphic deformation and mineral alignment.
Q29. Which rocks may preserve fossils of earlier plants and animals?
[SSC CGL Tier-I (12 December 2022, Shift 3)]
- (A) Metamorphic rocks
- (B) Intrusive igneous rocks
- (C) Sedimentary rocks
- (D) Extrusive igneous rocks
Answer: (C) Sedimentary rocks
Explanation: Sedimentary strata can bury and preserve organisms before their remains decay completely. Heat and melting during igneous or intense metamorphic processes usually destroy fossil evidence. This makes sedimentary Indian formations important for reconstructing ancient environments and life.
Q28. Which is a metamorphic rock?
[SSC MTS (5 July 2022, Shift 2)]
- (A) Halite
- (B) Marble
- (C) Limestone
- (D) Shale
Answer: (B) Marble
Explanation: Marble forms when limestone recrystallises under heat and pressure. Halite commonly precipitates as a chemical sediment, while shale and many limestones are sedimentary. Marble-rich belts in Rajasthan illustrate metamorphism within India’s ancient continental crust.
Q27. Which rock has been transformed by intense heat and pressure from a pre-existing rock?
[SSC CHSL (25 May 2022, Shift 2; 2021 cycle)]
- (A) Granite
- (B) Quartzite
- (C) Sandstone
- (D) Basalt
Answer: (B) Quartzite
Explanation: Quartzite is a hard metamorphic rock produced mainly from quartz-rich sandstone. Heat and pressure recrystallise its grains into a dense texture. Granite and basalt are igneous, while unaltered sandstone remains a sedimentary rock.
Q26. Consider: 1. Rocks can be transformed from their original forms. 2. Weathering, erosion and metamorphic action contribute to rock transformation. Which statements are correct?
[UPSC NDA General Ability Test (10 April 2022)]
- (A) 1 only
- (B) 2 only
- (C) Both 1 and 2
- (D) Neither 1 nor 2
Answer: (C) Both 1 and 2
Explanation: The rock cycle continually alters Earth’s materials. Weathering and erosion supply sediments for new sedimentary rocks, while heat and pressure generate metamorphic rocks. Both statements correctly recognise processes controlling the geological evolution of rocks.
Q25. The Thar or Marusthali region is believed to have been beneath the sea during which era?
[UPSC CDS (II) General Knowledge (4 September 2022)]
- (A) Cenozoic
- (B) Palaeozoic
- (C) Mesozoic
- (D) Archaean and Precambrian
Answer: (C) Mesozoic
Explanation: Parts of western Rajasthan preserve marine sediments and fossils indicating earlier marine conditions, notably in Mesozoic times. Although the present region is arid, its rocks record changing shorelines, deposition and tectonic evolution across long geological intervals.
Q24. Who proposed the concept of the rock cycle?
[UPPSC GIC Lecturer Geography (2021)]
- (A) W. M. Davis
- (B) G. K. Gilbert
- (C) James Hutton
- (D) J. W. Powell
Answer: (C) James Hutton
Explanation: James Hutton helped establish the idea of continuously changing rocks and geological recycling. Weathering, deposition, compaction, metamorphism, melting and crystallisation together form the rock cycle, a foundational idea for interpreting the geological development of Indian terrains.
Q23. Which of these is NOT considered a fundamental basis of plate-tectonic theory?
[UPPSC GIC Lecturer Geography (2021)]
- (A) Palaeomagnetism
- (B) Sea-floor spreading
- (C) Prehistoric climatic evidence
- (D) Rotation of poles
Answer: (D) Rotation of poles
Explanation: Palaeomagnetic records, sea-floor spreading and climatic indicators help reconstruct the movement of lithospheric plates and former continental positions. Simple ‘rotation of poles’ is not presented as a foundational line of evidence in the choices supplied by this examination.
Q22. Which is the only confirmed active volcano in India?
[SSC JE Electrical Engineering (24 March 2021, Evening)]
- (A) Deccan Traps
- (B) Barren Island
- (C) Baratang Island
- (D) Narcondam Island
Answer: (B) Barren Island
Explanation: Barren Island in the Andaman Sea contains India’s confirmed historically active volcano. Deccan Traps represent ancient, extensive lava flows rather than an active volcano, while the other named Andaman islands do not share Barren Island’s current eruptive status.
Q21. Which rocks form through lithification?
[SSC CHSL (4 August 2021, Shift 2; 2020 cycle)]
- (A) Igneous rocks
- (B) Metamorphic rocks
- (C) Sedimentary rocks
- (D) Primary rocks
Answer: (C) Sedimentary rocks
Explanation: Lithification consolidates loose sediment into rock by compaction and cementation. It explains the development of sandstone, shale and many other beds in India’s sedimentary basins. Igneous rocks solidify from melt, while metamorphic rocks change under heat and pressure.
