CUET UG Geography: Physical Geography - Landforms, Fluvial, Glacial, Coastal, Arid Landforms

Must-Know (15–20 detailed bullets)

• Fluvial landforms are created by erosion, transportation, and deposition of sediments by running water in rivers. Example: Ganga River forms alluvial fans and floodplains.
• Vertical erosion dominates in the upper course of a river, leading to V-shaped valleys and gorges. Example: Grand Canyon formed by the Colorado River.
• Waterfalls form when a river flows over alternating bands of hard and soft rock; the soft rock erodes faster. Example: Niagara Falls (USA-Canada border).
• Rapids develop where there are sudden changes in gradient or resistant rock bands in a river channel. Example: Rapids on the Narmada River near Jabalpur.
• Potholes are circular depressions formed by the abrasive action of pebbles and sand in swirling eddies at the riverbed. Process: Corrasion.
• Meanders are sinuous bends in a river in its middle course due to lateral erosion and deposition. Example: Meanders in the Kaveri River.
• Ox-bow lakes form when a meander neck is cut off due to erosion and deposition, isolating a curved lake. Example: Ox-bow lakes in the floodplain of the Brahmaputra.
• Delta formation occurs at river mouths where sediment deposition exceeds wave removal. Example: Sundarbans Delta (Ganga-Brahmaputra).
• Estuaries form when river mouths are submerged due to rising sea levels or land subsidence; no significant delta. Example: Narmada Estuary.
• Glacial landforms result from glacial erosion and deposition in high-altitude or high-latitude regions. Example: Himalayan glaciers shaping cirques and U-shaped valleys.
• Cirque (or corrie) is a bowl-shaped depression formed by glacial erosion at the head of a glacial valley. Example: Cirques in the Pir Panjal Range.
• Hanging valleys form when a smaller tributary glacier joins a larger one, leaving the tributary valley elevated. Example: Hanging valleys in Kashmir Valley.
• Moraines are accumulations of glacial till (unsorted debris) deposited directly by ice. Types: lateral, medial, terminal, ground moraine.
• Drumlins are elongated, teardrop-shaped hills formed by glacial deposition; steeper on the upstream side. Example: Drumlins in Ireland.
• Coastal landforms arise from wave erosion and deposition along shorelines. Key processes: abrasion, attrition, hydraulic action.
• Sea caves form by wave erosion along weak rock zones; when two caves meet, they form an arch. Example: Arches in the Andaman Islands.
• Stacks are isolated pillars of rock left after the collapse of a sea arch. Example: The Old Man of Hoy in Scotland.
• Beaches are depositional landforms made of sand, gravel, or shingle deposited by waves. Example: Marina Beach, Chennai.
• Bars and spits are ridge-like depositional features; spits are attached at one end and project into water. Example: Neelankarai Spit in Tamil Nadu.
• Arid landforms are shaped by wind erosion and deposition in deserts with sparse vegetation. Example: Thar Desert landforms.

Difficulty Level

Intermediate — Requires understanding of geomorphic processes and ability to distinguish between landforms formed by different agents (river, glacier, wind, waves), with specific examples.

Common CUET Traps

• Trap: Confusing ox-bow lakes with meanders or assuming all river bends become lakes.
  Avoid: Ox-bow lakes result only after cutoff of a meander loop due to neck erosion — not all meanders evolve into lakes.

• Trap: Believing that all deltas are triangular; some are bird’s foot or estuarine.
  Avoid: Deltas are classified based on shape and sediment supply; e.g., Mississippi has a bird’s-foot delta, while Narmada has no delta (forms estuary).

• Trap: Assuming wind is the only agent in arid regions; ignoring water action (flash floods).
  Avoid: Though wind dominates, ephemeral streams and sheet wash also shape arid landforms like wadis and bajadas.

Practice MCQs

1. Question: Which of the following landforms is primarily associated with the depositional activity of glaciers?
   A. Cirque
   B. Hanging valley
   C. Moraine
   D. Arete
   Answer: C
   Explanation: Moraines are formed by the deposition of glacial till.
   Why others fail: Cirque, hanging valley, and arete are erosional glacial landforms.

2. Question: An ox-bow lake is formed when:
   A. A glacier retreats and leaves a lake in a cirque
   B. A meander is cut off from the main river channel
   C. Waves erode a headland to form a stack
   D. River deposits sediment at its mouth
   Answer: B
   Explanation: Ox-bow lakes form due to meander cutoff in fluvial systems.
   Why others fail: Option A describes a tarn, C describes coastal erosion, D refers to delta formation.

3. Question: Which feature is NOT typically found in the upper course of a river?
   A. V-shaped valley
   B. Waterfall
   C. Delta
   D. Gorge
   Answer: C
   Explanation: Deltas form at the river mouth (lower course), not upper course.
   Why others fail: V-shaped valleys, waterfalls, and gorges are all upper-course features.

4. Question: The Sundarbans delta is formed by the combined action of which rivers?
   A. Indus and Jhelum
   B. Godavari and Krishna
   C. Ganga and Brahmaputra
   D. Narmada and Tapti
   Answer: C
   Explanation: The Sundarbans is the world’s largest delta formed by the Ganga and Brahmaputra rivers.
   Why others fail: Indus forms a small delta in Pakistan; Narmada and Tapti form estuaries.

5. Question: Which of the following coastal landforms results from the collapse of a sea arch?
   A. Stack
   B. Bar
   C. Spit
   D. Beach
   Answer: A
   Explanation: A stack is the remnant pillar of rock left after an arch collapses.
   Why others fail: Bar, spit, and beach are depositional features, not erosional remnants.

Last?Minute Revision

• V-shaped valley – fluvial erosion in upper course.
• U-shaped valley – glacial erosion (e.g., Himalayas).
• Potholes – formed by abrasion in riverbeds.
• Meander – lateral erosion in middle course; inner bank has slip-off slope, outer has undercut slope.
• Delta vs. Estuary: Delta forms with high sediment, low wave energy; estuary when river mouth is submerged.
• Ganga forms Sundarbans Delta; Narmada forms estuary.
• Cirque – bowl-shaped glacial hollow; may contain tarn after ice melts.
• Hanging valley – tributary glacial valley above main valley; often forms waterfall.
• Moraine – unsorted glacial deposit; lateral, medial, terminal types.
• Drumlins – glacial depositional feature; streamlined hills aligned with ice flow.
• Sea cave-arch-stack sequence due to coastal erosion.
• Stack – isolated pillar after arch collapse (e.g., Old Man of Hoy).
• Spit – depositional feature extending from coast into sea; one end attached.
• Bar – connects two headlands, closing off lagoon.
• Arid regions: wind erosion forms yardangs and ventifacts; deposition forms sand dunes.
• Barchan dune – crescent-shaped with horns facing windward; found in Thar Desert.
• Flash floods in deserts cause wadis (ephemeral streams).
• Deflation hollows – formed by wind removal of fine particles.
• NCERT term: "Fluvial" refers to river-related processes and landforms.
• Glacial till – unsorted, unstratified material deposited directly by ice.