Chapter 6 — Peninsular plateau, hills and escarpments

Exam fit: relief, drainage divides, geology and resource-location reasoning. Level: foundation to intermediate.

The Peninsular Plateau is a broad upland region south of the Northern Plains. Its old crystalline foundation, later geological events and long erosion history have produced an uneven mosaic: central highlands, the Deccan tableland, hill ranges, lava-covered tracts, river valleys and coastal escarpments. “Plateau” means an extensive elevated area, not a perfectly level surface. Its relief controls river direction, transport corridors, local rainfall and the distribution of some resources.

6.1 Central Highlands and Deccan Plateau

The Central Highlands lie broadly north of the Narmada valley and include uplands and ranges such as the Aravalli, Vindhya and Satpura systems in a generalised regional scheme. Their limits and subdivisions vary by textbook purpose. The Deccan Plateau occupies a large area south of the Narmada, broadly bounded by the Western and Eastern Ghats and sloping overall toward the east. This average slope helps explain why several major rivers flow eastward, though local structures, dams and tributaries make each basin distinct.

The plateau's surface includes rolling uplands, residual hills, dissected tablelands and broad valleys. Differential erosion means hard and soft rocks weather at different rates. A resistant layer can remain as a ridge or escarpment while weaker materials are worn down. The landscape therefore preserves both structure and process.

6.2 Western Ghats: an escarpment and climatic influence

The Western Ghats run roughly parallel to the Arabian Sea coast and form a significant relief barrier. Their elevated slopes interact with moisture-bearing monsoon winds. Where air is forced upward, rainfall may increase on windward slopes; descending air can create drier conditions eastward in some settings. The amount and pattern vary by latitude, season, local passes and circulation. The Ghats are not one uniform wall; gaps and valleys connect coastal and interior regions.

The western edge of the plateau often descends sharply toward the coastal lowland, producing an escarpment. Short west-flowing streams can descend steeply over relatively short distances. Their length and flow differ markedly from larger east-flowing plateau rivers, but do not infer a river's discharge solely from its direction.

6.3 Eastern Ghats: discontinuous hills and river gaps

The Eastern Ghats form a discontinuous chain of hills and highlands along the eastern side of the plateau. Rivers including the Mahanadi, Godavari, Krishna and Kaveri cross or cut through the ranges on their way to the Bay of Bengal. This interruption is one reason the Eastern Ghats are often described as less continuous than the Western Ghats. The individual hill groups have local names and varied rock histories; a national map should label only the best-known broad features to avoid false precision.

6.4 Aravalli, Vindhya and Satpura systems

The Aravalli system is an ancient, heavily eroded range in northwest India. Its present subdued relief reflects a long history of deformation and denudation. The Vindhya and Satpura ranges frame parts of central India and help shape the Narmada–Tapti region. They are useful orientation features, but they are not two unbroken walls across the country. Gaps, valleys and local basins permit rivers and transport routes to pass.

The Narmada flows west through a valley between the Vindhya and Satpura highlands in a broad textbook description. The Tapti (Tapi) also flows west, south of the Narmada. Their structural setting differs from many east-flowing plateau rivers. The next river chapter compares drainage and basin characteristics in detail.

6.5 Plateau, rocks and resources

The plateau includes ancient crystalline rocks, volcanic formations such as the Deccan basalt province, and sedimentary basins. This varied geology contributes to the occurrence of metallic minerals, building materials, groundwater aquifers and energy resources in particular places. But an atlas locator does not establish present reserves or output. Consult dated Indian Bureau of Mines and other official statistics for those claims; distinguish geological occurrence, measured resource, economically recoverable reserve and production in a specified year.

Mining and quarrying can support employment and supply industry while affecting forests, water, air and local livelihoods. A geography guide should describe those connections rather than imply that resources are either an automatic benefit or only a burden. Environmental clearance, rehabilitation, technology, transport, labour and markets shape the outcome.

6.6 Relief, rainfall and land use

Relief affects precipitation by lifting air and changing exposure to winds. It also influences soil depth, slope stability and irrigation costs. Plateau rainfall is seasonal and spatially variable. Valleys may channel winds; escarpments can produce sharp contrasts; drought risk depends on rainfall timing as well as annual totals. Crops respond to rainfall, soils, water storage, farm choices and market access. No crop is determined by landform alone.

Transport infrastructure negotiates this relief through passes, tunnels, bridges and winding alignments. A route map can show connectivity, but a static line cannot confirm road gradient, operating conditions or travel time. For exam questions, identify the broad corridor and explain why an escarpment or river valley matters.

6.7 Worked cross-section: coast to plateau interior

Draw a west-to-east profile: Arabian Sea coastal lowland, Western Ghats escarpment, elevated Deccan surface, an east-flowing river valley, Eastern Ghats hills and the Bay of Bengal coastal plain. Add arrows for moist monsoon flow and an eastward average drainage direction. Then mark exceptions: short west-flowing streams, local basins, passes through the Ghats and river gaps in the east. The profile is a reasoning aid rather than a precise elevation transect.

Worked map workshop

Build a west-to-east transect across peninsular India: Arabian Sea coastal lowland, Western Ghats escarpment, elevated Deccan surface, river valley, Eastern Ghats and the Bay of Bengal plain. The broad average slope helps explain why many large peninsular rivers flow east. Short west-flowing streams can descend rapidly because high relief is close to the coast in many places. The transect is a model; local basins and structures create exceptions.

Place the Narmada and Tapti on a separate central-India sketch because their westward flow follows broad structural and gradient controls. Do not force them into the eastward Deccan pattern. Compare a plateau's resistant ridge with a softer valley; differential erosion can maintain an escarpment while streams cut through weaker rock.

Finally connect physical geography to transport. A pass or river gap can provide a corridor, but engineering must address gradient, bridges, drainage, landslides and ecological impacts. A route line on an atlas shows spatial connection, not present operating condition or road safety. Use current departmental status reports for those claims.

Chapter recall

• The plateau is elevated but varied and dissected; it is not a flat table.
• The Deccan slopes broadly eastward, helping explain many east-flowing river systems.
• The Western Ghats form a major escarpment and influence monsoon rainfall; local gaps and contrasts matter.
• The Eastern Ghats are discontinuous and crossed by major rivers.
• The Aravalli, Vindhya and Satpura systems are useful orientation features, not continuous barriers.

The Deccan, Western Ghats and Eastern Ghats shape plateau drainage.

Chapter practice MCQs

1. A plateau is best described as:

A. a deep ocean trench

B. a flat plain at sea level in every case

C. an extensive elevated area that may be dissected

D. a river mouth

Answer: C. Plateaus are uplands, but erosion, valleys and escarpments create substantial local relief.

2. The broad average slope of much of the Deccan Plateau helps explain why many major rivers flow:

A. north into the Himalaya

B. west into the Arabian Sea only

C. south into the Antarctic Ocean

D. east toward the Bay of Bengal

Answer: D. The plateau generally slopes eastward, although each river basin has its own controls and exceptions.

3. The Western Ghats run broadly:

A. parallel to India's west coast

B. across the northern plains from east to west

C. along the Ganga delta only

D. around Lakshadweep

Answer: A. The range follows the western side of peninsular India near the Arabian Sea coast.

4. Which range is generally more discontinuous and crossed by several major east-flowing rivers?

A. Greater Himalaya

B. Eastern Ghats

C. Karakoram

D. Shiwalik only

Answer: B. The Eastern Ghats are discontinuous in many stretches and interrupted by rivers flowing toward the Bay of Bengal.

5. An escarpment is:

A. a tidal river mouth

B. a soil horizon

C. a pronounced slope or cliff between surfaces of different elevation

D. a glacier lake

Answer: C. Escarpments create sharp relief transitions and may influence drainage, access and rainfall.

6. Which two major rivers flow westward through the broad Narmada–Tapti region?

A. Godavari and Kaveri

B. Ganga and Yamuna

C. Mahanadi and Brahmaputra

D. Narmada and Tapti

Answer: D. Narmada and Tapti are prominent west-flowing peninsular rivers; basin details are treated later.

7. Differential erosion means:

A. rocks of differing resistance wear down at different rates

B. every rock erodes identically

C. only rivers can alter relief

D. a map is printed at different scales

Answer: A. Rock strength and structure influence how quickly landforms are lowered or remain as ridges.

8. The Aravalli system is commonly described as:

A. a recent coral reef

B. an ancient, heavily eroded range

C. a chain of active volcanoes along the Bay of Bengal

D. a river delta

Answer: B. Long erosion has subdued much of the ancient range's relief compared with younger mountain systems.

9. Which statement about the Vindhya and Satpura ranges is safest?

A. They form one unbroken wall across every state.

B. They lie entirely under the sea.

C. They are broad central-India orientation features with gaps and local variation.

D. They are river basins, not ranges.

Answer: C. Generalised maps show major highlands, but the relief includes gaps, valleys and varied local forms.

10. The Narmada is broadly associated with a valley between the:

A. Himalaya and Shiwaliks

B. Eastern and Western coastal plains

C. Aravalli and Himalaya only

D. Vindhya and Satpura highlands

Answer: D. This is a standard broad physiographic relationship; local topography is more complex.

11. Which statement correctly describes a plateau resource map?

A. It can show general occurrence zones but not automatically current reserves or output.

B. It proves the exact annual production of every mine.

C. It guarantees a deposit is profitable.

D. It replaces official statistical yearbooks.

Answer: A. Occurrence, resource, reserve and yearly production are different evidence categories.

12. Orographic rainfall on a mountain slope occurs chiefly because air:

A. sinks underground

B. is forced upward and cools

C. stops moving at the coast

D. becomes a river

Answer: B. Uplift can cool moist air and support condensation; rainfall amount depends on broader atmospheric conditions.

13. A west-facing slope and nearby east-facing slope may differ in rainfall because of:

A. political district names

B. the map's font

C. wind exposure, relief and rain-shadow effects

D. the time zone alone

Answer: C. Aspect and wind direction can create contrasts, though local circulation modifies the pattern.

14. Which rivers cross or cut through the Eastern Ghats on their way to the Bay of Bengal?

A. Narmada and Tapti only

B. Indus and Jhelum only

C. Luni and Ghaggar only

D. Godavari, Krishna and Kaveri among others

Answer: D. Several large east-flowing rivers traverse the discontinuous Eastern Ghats.

15. Which description of the Peninsular Plateau is inaccurate?

A. It is one perfectly level surface with no local relief.

B. It includes varied rock formations and dissected terrain.

C. It contains river valleys and escarpments.

D. It is broadly underlain by old geological foundations.

Answer: A. The plateau is a broad upland region with substantial variation in elevation and structure.

16. A river divide is important because it:

A. marks the exact annual rainfall total

B. separates drainage toward different basins

C. guarantees a road connection

D. is identical to a state boundary

Answer: B. Higher ground directs runoff toward different drainage systems, although human transfers can cross divides.

17. A route crossing a Western Ghats pass may be affected by:

A. latitude alone

B. no physical constraints

C. gradient, rainfall, slope stability and maintenance

D. sea salinity only

Answer: C. Relief and weather shape infrastructure design and operating conditions; current status needs current sources.

18. Which is a correct relation between rock type and landform?

A. Rock type never affects topography.

B. Every basalt flow forms a present-day volcano.

C. All sedimentary rocks form plains.

D. Resistant and weak layers can erode differently and shape ridges or scarps.

Answer: D. Differential resistance is one control on relief, alongside structure, climate and time.

19. A short west-flowing stream may descend steeply because:

A. the plateau edge lies relatively near the coast

B. all west-flowing rivers begin in the sea

C. the Earth rotates faster near the coast

D. deltas are always at high elevation

Answer: A. In many western settings, high terrain is close to the coastal plain, creating short steep drainage routes.

20. Which factor does not determine a crop pattern by itself?

A. Water availability

B. Landform alone

C. Soil and climate

D. Farm decisions and market access

Answer: B. Crop choice reflects multiple physical, economic and institutional factors, not relief alone.

21. What does a west-to-east plateau cross-section help show?

A. Exact rainfall tomorrow

B. District tax collections

C. Coastal plain, Western Ghats, plateau interior, Eastern Ghats and coastal lowland

D. Village property lines

Answer: C. A cross-section clarifies broad elevation relationships and drainage direction.

22. The term “Deccan Traps” refers broadly to:

A. a chain of Himalayan passes

B. alluvial levees in the Ganga plain

C. coral islands in the Arabian Sea

D. extensive basaltic lava formations with step-like topography

Answer: D. Repeated basalt flows and later erosion help produce stepped landforms.

23. Which is a sound conclusion about mining and development?

A. Mineral occurrence can support activity, but impacts and economic outcomes depend on access, safeguards and markets.

B. A mineral guarantees prosperity.

C. Mining has no environmental effects.

D. Transport is irrelevant to resource use.

Answer: A. Resources create possibilities and trade-offs; institutions, infrastructure and environmental management matter.

24. Why should a study guide avoid drawing exact disputed boundaries on a thematic plateau map?

A. Rivers cannot be mapped.

B. Generalised teaching diagrams are not certified political or navigation maps.

C. The plateau has no boundaries.

D. All maps are photographs.

Answer: B. Thematic locators should state their limits and use appropriate official products for boundary or navigation needs.

25. Which regional description is accurate?

A. Western Ghats—Northern Plains; Eastern Ghats—Thar Desert

B. Western Ghats—river delta; Eastern Ghats—ocean trench

C. Western Ghats—major west-side relief barrier; Eastern Ghats—discontinuous eastern hills

D. Both Ghats—continuous snowfields

Answer: C. This captures their broad position and continuity without implying uniform local terrain.

26. A plateau is “dissected” when:

A. it is submerged under an ocean

B. it has no rivers

C. all slopes disappear

D. streams and erosion cut valleys into its surface

Answer: D. Drainage incision divides an upland surface into ridges, valleys and smaller tablelands.

27. Which data would be needed to state a pass's current travel condition?

A. Current official road or administration advisory

B. An old relief map alone

C. A geological age chart

D. A crop yield table

Answer: A. Conditions change with weather, landslides and maintenance, so operational claims require a current source.

28. Which concept links plateau relief to river direction?

A. Moon phases only

B. Surface gradient and drainage divides

C. Census category

D. Coastal salinity only

Answer: B. Water generally follows gradients within basins, while divides separate its broad direction of flow.