Geology 2024 Paper I 50 marks Discuss

Q3

(a) Discuss in detail, with diagrams, the landforms and features resulting from deposition by rivers. (20 marks) (b) Describe the characteristics of Indian remote sensing satellites. (15 marks) (c) Diagrammatically explain the formation of normal fault, strike-slip fault and thrust fault with the help of stress ellipsoid. (15 marks)

हिंदी में प्रश्न पढ़ें

(a) नदी निक्षेपण द्वारा निर्मित भू-आकृतियों एवं अभिलक्षणों का चित्र सहित विस्तृत वर्णन कीजिए। (20 अंक) (b) भारतीय सूदूर संवेदन उपग्रहों की विशेषताओं का वर्णन कीजिए। (15 अंक) (c) प्रतिबल दीर्घवृत्तज की सहायता से सामान्य भ्रंश, नतिलम्ब सर्पण भ्रंश तथा क्षेप भ्रंश के निर्माण की सचित्र व्याख्या कीजिए। (15 अंक)

Directive word: Discuss

This question asks you to discuss. The directive word signals the depth of analysis expected, the structure of your answer, and the weight of evidence you must bring.

See our UPSC directive words guide for a full breakdown of how to respond to each command word.

How this answer will be evaluated

Approach

The directive 'discuss' in part (a) demands a comprehensive, analytical treatment with multiple perspectives, while parts (b) and (c) require 'describe' and 'explain' respectively. Allocate approximately 40% of time/words to part (a) given its 20 marks, 30% each to parts (b) and (c). Structure: brief integrated introduction → systematic treatment of (a) fluvial depositional landforms with process-form relationships, (b) IRS series technical specifications and applications, (c) fault mechanics with stress ellipsoid analysis → synthesis highlighting geomorphological-structural-tectonic connections.

Key points expected

  • Part (a): Distinguish between channel deposits (point bars, channel bars, riffle-pool sequences) and overbank deposits (natural levees, crevasse splays, floodplains); explain terrace formation and alluvial fan dynamics with Indian examples (Kosi megafan, Indo-Gangetic plains)
  • Part (a): Analyze downstream fining, sediment sorting mechanisms, and the role of base level change in aggradation; include at least 3 labeled diagrams showing cross-sections of meander scrolls, levee-backswamp topography, and terrace staircase
  • Part (b): Detail IRS-1C/1D, Resourcesat-1/2, Cartosat series specifications (spatial resolution, spectral bands, revisit capability); explain LISS-III, LISS-IV, PAN, and AWiFS sensors; mention RISAT for all-weather capability and their roles in groundwater exploration, wasteland mapping, and disaster management
  • Part (c): Construct Mohr stress circle and σ1-σ2-σ3 ellipsoid for each fault type; show σ1 orientation as vertical for normal, horizontal for thrust, and intermediate for strike-slip; relate to Anderson's theory of faulting and plate boundary settings
  • Part (c): Correlate fault types with specific Indian examples—Sohan fault (normal), Kutch strike-slip system, Main Boundary Thrust (Himalayan thrust); explain fault plane solutions and focal mechanisms where relevant

Evaluation rubric

DimensionWeightMax marksExcellentAveragePoor
Concept correctness22%11Demonstrates precise understanding of fluvial sedimentation dynamics (part a), IRS sensor specifications and orbital characteristics (part b), and stress tensor-fault orientation relationships per Andersonian mechanics (part c); correctly distinguishes between extensional, compressional, and strike-slip regimesCovers basic concepts adequately but confuses some technical details (e.g., LISS-III vs LISS-IV resolutions, or σ1/σ3 orientation in thrust faults); descriptions are accurate but lack mechanistic depthMajor conceptual errors such as confusing depositional with erosional landforms, misidentifying satellite sensors, or showing σ1 horizontal for normal faults; fundamental misunderstanding of stress ellipsoid geometry
Diagram / cross-section24%12Provides minimum 5 high-quality diagrams: for (a) labeled 3D block of point bar migration, levee-backswamp cross-section, and terrace sequence; for (b) schematic of IRS payload configuration; for (c) three stress ellipsoids with σ1, σ2, σ3 axes and corresponding fault planes with sense of displacement arrowsIncludes 3-4 diagrams with basic labeling but missing critical elements (e.g., stress axes not shown on ellipsoids, or missing vertical exaggeration in fluvial sections); diagrams support text but do not independently convey full informationFewer than 3 diagrams, or diagrams with serious errors (wrong fault geometry, mislabeled stress axes, schematic satellites without sensor detail); diagrams appear decorative rather than explanatory
Field evidence18%9Cites specific Indian field examples for each part: for (a) mentions Kosi megafan avulsion history, Ganga-Yamuna doab sediments, or Narmada-Tapi alluvial sequences; for (c) references Kutch 2001 earthquake focal mechanisms, Main Central Thrust exposure at Ramgarh, or Sohan graben morphologyMentions generic examples (Himalayan rivers, Indian satellites) without specific localities or case studies; field evidence is implied rather than explicitly statedNo Indian examples; relies entirely on textbook generic descriptions (Mississippi River, San Andreas fault) without connecting to subcontinental geology
Quantitative reasoning16%8Includes quantitative specifications: for (b) IRS spatial resolutions (LISS-III: 23.5m, LISS-IV: 5.8m, Cartosat-1: 2.5m), spectral bands, revisit periods; for (c) approximate dip angles (normal: 60°, thrust: 30°), stress magnitude relationships; for (a) grain size trends, channel dimensions where relevantMentions some numerical values but with inaccuracies or omissions; quantitative treatment is present but not systematically integrated across all three partsEntirely qualitative treatment; no numerical data on satellite specifications, fault geometry angles, or sedimentological parameters
Indian / economic relevance20%10Explicitly connects all three parts to Indian applications: fluvial landforms to groundwater recharge, flood risk (Kosi embankment failures), and agricultural productivity of Indo-Gangetic plains; IRS to NNRMS, watershed management, and mineral exploration; fault mechanics to seismic hazard assessment in Himalaya and stable continental regionsMakes passing reference to Indian relevance (e.g., mentions flood control or earthquake hazard) without developed analysis; economic significance stated but not elaboratedTreats question as purely academic exercise with no connection to Indian developmental needs, disaster management, or natural resource utilization

Practice this exact question

Write your answer, then get a detailed evaluation from our AI trained on UPSC's answer-writing standards. Free first evaluation — no signup needed to start.

Evaluate my answer →

More from Geology 2024 Paper I