Landforms & Their Evolution – NDA Geography PYQs

NDA 2022-II

Q. 1. A spit is a:

(a) Coastal erosional feature

(b) Tidal current feature

(c) Coastal depositional feature

(d) Wind erosional feature

Answer: (c) Coastal depositional feature

Explanation: A Spit is a coastal depositional featurea narrow ridge of sand or gravel that extends out from the coast into the sea or a bay. Spits are formed by longshore driftthe transportation of sand along the coast by waves approaching at an angle. When the coastline bends (at a bay, estuary, or headland), longshore drift continues in its original direction and deposits material in the water, gradually extending the spit. Famous examples: Spurn Head (England), the Long Spit (Chesil Beach), Dungeness (Kent). If the spit grows across a bay to connect to the opposite shore, it becomes a bar. Concept Tested: Spitcoastal depositional feature; sand ridge extending from coast into sea, formed by longshore drift

NDA 2021-I

Q. 2. Tombolo is:

(a) A sand bar connecting an island to the mainland or to another island

(b) A long spit formed at the mouth of a river

(c) A spit connecting two headlands

(d) A sand dune formed near a river mouth

Answer: (a) A sand bar connecting an island to the mainland or to another island

Explanation: A Tombolo is a sand or gravel bar (or spit) that connects an offshore island to the mainland, or connects one island to another. It is formed by longshore drift depositing sediment between the island and the coast. The word comes from the Italian “tombolo” (meaning “mound”). A famous example is The Bar connecting Chesil Beach (England) to the Isle of Portland. A tombolo differs from a spit (which projects from the coast into the sea) and from a bar (which closes off a bay). Concept Tested: Tombolosand bar connecting an island to the mainland; formed by coastal deposition (longshore drift)

NDA 2020-I

Q. 3. A Delta is not formed at the mouth of a river, if there is:

(a) A large and continuous supply of sediment

(b) Shallow and wide shelf near the river mouth

(c) Strong and persistent marine currents

(d) A long stretch of gentle gradient

Answer: (c) Strong and persistent marine currents

Explanation: A delta forms when a river deposits its sediment at the mouth as it meets a relatively still water body. Strong and persistent marine (sea/ocean) currents prevent delta formation by sweeping away sediment as fast as the river deposits it. Other factors favouring delta formation: large sediment supply (a), shallow shelf (b), and gentle gradient (d)these all HELP delta formation, not prevent it. Some rivers do not form deltas despite carrying sedimentthe Amazon has no true delta because powerful tidal currents disperse its load; the Indus’s delta is small because much water is diverted for irrigation. Concept Tested: Delta does NOT form when strong marine currents remove sediment as fast as the river deposits it

NDA 2017-II

Q. 4. Dolines are karst depressions formed mainly by:

(a) Wind erosion

(b) Chemical solution

(c) Glacial action

(d) River action

Answer: (b) Chemical solution

Explanation: Dolines (also called sinkholes or shakeholes) are enclosed circular depressions in karst landscapes. They are formed primarily by the chemical dissolution (solution) of limestone by slightly acidic rainwater. When the limestone below the surface dissolves, the overlying material collapses or sinks inward, creating a bowl-shaped or funnel-shaped depression at the surface. Dolines are among the most characteristic karst landforms. They can also form by mechanical collapse of a cave roof, but chemical solution is the primary process. Concept Tested: Dolineskarst sinkholes formed by chemical solution (dissolution) of limestone; NOT wind, glacial, or river action

NDA 2016-II

Q. 5. Which type of rock commonly gives rise to Karst topography?

(a) Granite

(b) Basalt

(c) Sandstone

(d) Limestone

Answer: (d) Limestone

Explanation: Karst topography is a distinctive landscape formed in areas underlain by soluble bedrockprimarily limestone (and sometimes dolomite, marble, or gypsum). The word “karst” comes from the Karst plateau in Slovenia. When rainwater (slightly acidic with CO₂) percolates through limestone, it slowly dissolves the rock through carbonation, creating features like sinkholes (dolines), caves, stalactites, stalagmites, disappearing streams, and poljes. Granite, basalt, and sandstone are not readily soluble and do not produce karst landscapes. Concept Tested: Karst topographyformed in limestone (soluble rock); dissolution by carbonic acid creates caves, sinkholes, and stalactites

NDA 2015-II

Q. 6. Which one of the following is a glacial depositional landform?

(a) Cirque

(b) Fiord

(c) U-shaped valley

(d) Drumlin

Answer: (d) Drumlin

Explanation: Drumlins are elongated, streamlined hills of glacial till (unsorted sediment). They are formed beneath a moving glacier by the ice moulding and compressing till into oval, teardrop-shaped hills. They indicate the direction of former ice movement (the blunt end faces the oncoming ice). Circue (a), Fiord (b), and U-shaped valley (c) are all glacial EROSION featurescarved by the glacier cutting into rock. Concept Tested: Drumlinglacial DEPOSITION feature (streamlined till hill); Cirque, Fiord, U-valley are glacial erosion

NDA 2014-II

Q. 7. What is an Esker?

(a) A long winding ridge of sand and gravel deposited by a stream on a flat plain

(b) A long winding ridge of sand and gravel deposited by a glacial melt water stream

(c) A recessional moraine at the foot of a glacier

(d) A ridge deposited by a river in flood

Answer: (b) A long winding ridge of sand and gravel deposited by a glacial melt water stream

Explanation: An Esker is a long, sinuous (winding) ridge of sorted sand and gravel, typically running in the direction of former ice flow. It is deposited by meltwater streams flowing INSIDE or beneath a glacier through subglacial tunnels. When the glacier melts, the tunnel collapses, leaving the sand and gravel ridge behind as a raised feature on the landscape. Eskers are found in formerly glaciated regions (e.g., Scandinavia, Canada, Ireland). Concept Tested: Eskersinuous ridge of sand/gravel deposited by subglacial meltwater streams inside a glacier

NDA 2013-I

Q. 8. A terminal moraine is:

(a) A ridge of rock fragments left in the middle of a glaciated valley

(b) A ridge deposited by a stream flowing under a glacier

(c) A ridge of rock fragments deposited at the furthest extent of a glacier’s advance

(d) A ridge of rock fragments deposited along the side of a glacier

Answer: (c) A ridge of rock fragments deposited at the furthest extent of a glacier’s advance

Explanation: Moraines are accumulations of rock debris (till) deposited by glaciers. Types: Terminal moraine (c)deposited at the furthest point (snout) that a glacier advances; marks the maximum extent of glaciation. It forms a ridge across the glacial valley. Lateral morainealong the sides of a glacier (option d). Medial morainein the middle of a glacier (where two glaciers merge) (option a). Eskera sinuous ridge deposited by a meltwater stream under a glacier (option b). This describes an esker, not a moraine. Concept Tested: Terminal moraineridge of debris at the furthest advance of a glacier; marks maximum glacial extent

★ JOVIK Exam Insight Glacial deposition features for NDA: Terminal moraineat the glacier’s snout (furthest advance). Lateral morainealong the sides of a glacier. Medial morainein the middle (where two glaciers merge). Ground morainesheet of till beneath and around the glacier. Drumlinstreamlined oval hill of glacial till; formed under moving ice. Eskersinuous ridge of sand/gravel; deposited by meltwater streams INSIDE the glacier. Kettledepression from melting buried ice block.

NDA 2012-II

Q. 9. What is a Crevasse?

(a) A crack in the ocean floor

(b) A deep valley in a mountain

(c) A crack in a glacier

(d) A crack in the Earth’s crust

Answer: (c) A crack in a glacier

Explanation: A Crevasse is a deep crack or fracture in a glacier’s ice body. Crevasses form because glacial ice is brittlewhen a glacier moves over uneven terrain or changes speed, the ice cracks. Crevasses can be extremely deep (up to 50 metres) and are a major hazard for mountaineers. They should not be confused with: a crevice (any narrow crack in rock), a gorge (river valley), or a fault (break in Earth’s crust). Concept Tested: Crevassea deep crack in a glacier; formed when brittle ice fractures during glacier movement

NDA 2012-I

Q. 10. Ox-bow lakes are formed when:

(a) A river bifurcates in a flat plain

(b) A meander loop is cut off from the main stream

(c) Sea water enters a river channel

(d) A river changes its course and cuts a new channel

Answer: (b) A meander loop is cut off from the main stream

Explanation: An ox-bow lake (horseshoe lake) is formed when a meandering river cuts off one of its meander loops. As a river meanders, the outer bank of each bend is eroded while the inner bank is deposited upon. The meander loops become increasingly pronounced until the river breaks through at the neck of the loop (usually during a flood). The main river takes the shorter, straighter course, leaving the old meander loop as a curved lakecalled an ox-bow lake (named for its resemblance to the U-shaped yoke worn by oxen). Concept Tested: Ox-bow lakeformed when a meander neck is cut through; isolated meander loop becomes a crescent lake

NDA 2011-I

Q. 11. Yazoo streams are:

(a) Streams flowing parallel to the main stream on the floodplain

(b) Streams that join the main stream at right angles

(c) Streams found only in the upper course of rivers

(d) Streams that flow in opposite direction to the main stream

Answer: (a) Streams flowing parallel to the main stream on the floodplain

Explanation: Yazoo streams (also called yazoo tributaries) are small streams that flow parallel to the main river on its floodplain, unable to join it directly because they are blocked by natural levees built up along the main river’s banks. The term comes from the Yazoo River in Mississippi, USA, which flows parallel to the Mississippi River for a considerable distance before joining it. They are characteristic features of mature or old-age rivers with extensive floodplains. Concept Tested: Yazoo streamsparallel tributaries blocked by natural levees on the floodplain from joining the main river

Q. 12. A peneplain is a feature associated with the stage of:

(a) Youth of a river

(b) Maturity of a river

(c) Old age of a river

(d) Rejuvenation of a river

Answer: (c) Old age of a river

Explanation: In William Morris Davis’s cycle of erosion (Geographical Cycle), landforms evolve through three stages: Youth, Maturity, and Old Age. A peneplain is the final erosional surface associated with old ageit is a nearly flat or gently rolling plain produced by prolonged erosion reducing a landscape to near sea level (base level). The term comes from the Latin “paene” = almost + “planum” = plain. In Youth, rivers erode vigorously (V-valleys, waterfalls). In Maturity, lateral erosion widens valleys. In Old Age, rivers meander extensively on broad floodplains, gradually wearing the landscape to a peneplain. Concept Tested: Peneplainnearly flat erosional surface associated with the old age stage of river/landscape erosion cycle

NDA 2010-I

Q. 13. V-shaped valleys are usually formed by:

(a) River action

(b) Faulting

(c) Glacial action

(d) Volcanic action

Answer: (a) River action

Explanation: V-shaped valleys are formed by river (fluvial) erosion in the upper course of a river where vertical (downcutting) erosion dominates. The river cuts steeply downward while the sides of the valley are weathered and eroded, giving the characteristic V shape. In contrast, glacial valleys have a U-shapethe glacier carves out the floor and sides to produce a broad, flat-bottomed U-shaped valley. Faulting can create rift valleys (with flat floors and steep sides)not typical V-shapes. Concept Tested: V-shaped valleysformed by river (fluvial) erosion in upper course; vertical downcutting dominates

★ JOVIK Exam Insight River valley shapes for NDA: V-shaped valley → River erosion (upper course, steep gradient, vertical erosion). U-shaped valley → Glacial erosion (glacier carves flat bottom and steep sides). Rift valley → Tectonic faulting (block drops between parallel faults). Gorge/Canyon → Vertical river erosion + resistant rock (e.g., Grand Canyon).

NDA 2009-II

Q. 14. Which one of the following is deposited when a mountain stream enters a plain?

(a) Levee

(b) Peneplain

(c) Watershed

(d) Alluvial fan

Answer: (d) Alluvial fan

Explanation: When a fast-flowing mountain stream loses velocity as it reaches a plain at the base of a mountain, it drops its sediment load rapidly, forming an alluvial fana fan-shaped deposit of sediment. The sudden decrease in gradient (slope) causes the stream to lose carrying capacity, and coarser sediment is deposited first, finer material further out. Where multiple alluvial fans merge, they form an alluvial apron or bajada. Levees form along river banks during flooding (fluvial deposition, not at mountain base). Peneplain is an erosion landform. Concept Tested: Alluvial fanfan-shaped deposition at the base of a mountain where a stream loses velocity on the plain

Q. 15. Meanders are formed in the:

(a) Upper course of a river

(b) Middle and lower course of a river

(c) Mountain course of a river

(d) At the mouth of a river

Answer: (b) Middle and lower course of a river

Explanation: Meanders are large, sinuous bends in a river. They form in the middle and lower course of a river where: 1. The gradient (slope) is gentle. 2. The river has a large volume of water and a broad floodplain. 3. Lateral erosion dominates over vertical erosion. In the upper course, the river has a steep gradient and primarily erodes verticallyforming V-shaped valleys. Meanders require a flat, wide floodplain to develop. Concept Tested: Meanders form in the middle and lower coursegentle gradient, lateral erosion, broad floodplain

NDA 2008-I

Q. 16. River capture or River piracy refers to:

(a) One river draining into another river

(b) Submergence of river into underground channel

(c) Headward erosion of one stream into the headwaters of another

(d) Joining of two tributaries at confluence

Answer: (c) Headward erosion of one stream into the headwaters of another

Explanation: River capture (also called stream piracy or beheading) occurs when one stream erodes headward (backward from its headwaters) and eventually cuts through a drainage divide, intercepting the headwaters of a neighbouring stream. The stream that does the capturing is called the “captor” or “pirate” stream. The captured stream’s upper portion is diverted into the pirate stream’s drainage basin. The elbow of capture (the sharp bend in the river) and the wind gap (a dry valley at the former divide) are evidence of river capture. Concept Tested: River captureheadward erosion of one stream cuts through watershed, capturing another river’s headwaters

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