India's Physiographic Divisions
India's physical landscape is remarkably diverse, shaped by tectonic forces, weathering, and fluvial processes over millions of years. The country can be divided into six major physiographic divisions.
Overview of Physiographic Divisions
| Division | Approximate Area | Key Feature | Geological Age |
|---|---|---|---|
| The Himalayan Mountains | ~5 lakh sq km | Young fold mountains; highest peaks | Tertiary (Cenozoic) |
| The Northern Plains | ~7 lakh sq km | Alluvial deposits of Indus-Ganga-Brahmaputra | Quaternary |
| The Peninsular Plateau | ~16 lakh sq km | Oldest landmass; igneous & metamorphic rocks | Precambrian (Archaean) |
| The Indian Desert | ~2 lakh sq km | Arid landscape; sand dunes (Thar) | Quaternary |
| The Coastal Plains | Narrow strips along coasts | Marine deposits; lagoons and deltas | Recent |
| The Islands | ~8,249 sq km | Andaman & Nicobar (tectonic); Lakshadweep (coral) | Tertiary to Recent |
The Himalayan Mountains
The Himalayas stretch in a west-east arc from the Indus to the Brahmaputra, spanning approximately 2,400 km in length and 150-400 km in width.
Longitudinal Divisions of the Himalayas
| Range | Local Name | Average Height | Width | Key Features |
|---|---|---|---|---|
| Greater Himalayas | Himadri | ~6,100 m | 25 km | Perpetual snow; peaks above 8,000 m; Kangchenjunga (8,598 m) |
| Lesser Himalayas | Himachal | 3,500-5,000 m | 60-80 km | Pir Panjal, Dhauladhar, Mussoorie Range; hill stations |
| Outer Himalayas | Shivaliks | 600-1,500 m | 10-50 km | Youngest range; composed of unconsolidated sediments; Duns |
Major Himalayan Peaks in India
| Peak | Height (m) | State/Region |
|---|---|---|
| K2 (Godwin-Austen) | 8,611 | Karakoram Range (PoK) |
| Kangchenjunga | 8,598 | Sikkim |
| Nanda Devi | 7,816 | Uttarakhand |
| Kamet | 7,756 | Uttarakhand |
| Saltoro Kangri | 7,742 | Karakoram (Ladakh) |
Regional Divisions of the Himalayas
| Region | Between | States Covered |
|---|---|---|
| Punjab/Kashmir Himalayas | Indus to Sutlej | J&K, Ladakh, Himachal Pradesh |
| Kumaon Himalayas | Sutlej to Kali | Himachal Pradesh, Uttarakhand |
| Nepal Himalayas | Kali to Tista | Nepal (international) |
| Assam Himalayas | Tista to Dihang | Sikkim, Arunachal Pradesh |
The Northern Plains
The Indo-Gangetic plain is formed by the alluvial deposits of the Indus, Ganga, and Brahmaputra river systems. It stretches about 2,400 km in length and 150-300 km in width.
Zones of the Northern Plains
| Zone | Description | Location |
|---|---|---|
| Bhabar | Narrow belt of pebble-studded rocks (8-16 km wide); streams disappear | Along Shivalik foothills |
| Terai | Marshy, swampy zone; dense forests; re-emergence of streams | South of Bhabar |
| Bhangar | Older alluvium; above flood level; contains kankar (calcareous nodules) | Higher terraces of river valleys |
| Khadar | Newer alluvium; renewed by annual floods; highly fertile | Flood plains of rivers |
The Peninsular Plateau
The Peninsular Plateau is India's oldest and most stable landmass, composed primarily of igneous and metamorphic rocks. It is bounded by the Aravalli Range in the northwest, the Vindhya and Satpura ranges in the north, and flanked by the Western and Eastern Ghats.
Sub-divisions of the Peninsular Plateau
| Sub-division | Key Features |
|---|---|
| Central Highlands | North of Narmada; includes Malwa Plateau, Bundelkhand, Baghelkhand; slope towards north |
| Deccan Plateau | South of Narmada; triangular; higher on western side; slopes eastward |
| Western Ghats | Average height 900-1600 m; continuous range; higher than Eastern Ghats |
| Eastern Ghats | Discontinuous; average 600 m; cut by Godavari, Krishna, Kaveri rivers |
Important Peaks of Western and Eastern Ghats
| Peak | Height (m) | Range |
|---|---|---|
| Anamudi | 2,695 | Western Ghats (Kerala) |
| Dodda Betta | 2,637 | Western Ghats (Nilgiris, Tamil Nadu) |
| Mahendragiri | 1,501 | Eastern Ghats (Odisha) |
Major Rivers of India
India's rivers are classified into two major groups based on their origin: Himalayan rivers (perennial, snow-fed) and Peninsular rivers (seasonal, rain-fed).
Major Rivers: Origin, Length, and Tributaries
| River | Origin | Length (km) | Drains Into | Major Tributaries |
|---|---|---|---|---|
| Ganga | Gangotri Glacier, Uttarakhand | 2,525 | Bay of Bengal | Yamuna, Ramganga, Ghaghra, Gandak, Kosi, Son, Mahananda |
| Brahmaputra | Kailash Range (Tibet) at ~5,150 m | 2,900 (total) | Bay of Bengal | Dibang, Lohit, Subansiri, Manas, Tista, Dhansiri |
| Indus | Near Mansarovar Lake, Tibet | 2,880 (709 in India) | Arabian Sea | Jhelum, Chenab, Ravi, Beas, Sutlej |
| Godavari | Trimbakeshwar, Nashik (Maharashtra) at 1,067 m | 1,465 | Bay of Bengal | Pranhita, Indravathi, Sabari, Manjira, Purna, Pravara |
| Krishna | Mahabaleshwar, Maharashtra | 1,400 | Bay of Bengal | Bhima, Tungabhadra, Koyna, Musi |
| Yamuna | Yamunotri Glacier, Uttarakhand | 1,376 | Merges with Ganga at Prayagraj | Chambal, Betwa, Ken, Sindh |
| Narmada | Amarkantak, Madhya Pradesh | 1,312 | Arabian Sea | Tawa, Hiran, Barna, Kolar |
| Kaveri | Talakaveri, Kodagu (Karnataka) | ~800 | Bay of Bengal | Hemavati, Kabini, Shimsha, Arkavati |
Drainage Patterns
| Pattern | Description | Indian Example |
|---|---|---|
| Dendritic | Tree-like branching; develops on uniform slopes | Northern Plains rivers |
| Trellis | Main stream joined by tributaries at right angles | Subarnarekha basin |
| Radial | Rivers flow outward from a central high point | Rivers originating from Amarkantak |
| Rectangular | Right-angle bends due to jointed rocks | Chambal drainage in parts |
| Centripetal | Rivers converge into a depression | Loktak Lake drainage |
Himalayan vs. Peninsular Rivers
| Feature | Himalayan Rivers | Peninsular Rivers |
|---|---|---|
| Source | Glaciers and snowmelt | Rainfall and springs |
| Flow | Perennial | Seasonal (except west-flowing) |
| Catchment | Large | Relatively smaller |
| Gradient | Steep in upper; gentle in plains | Gentle; mature stage |
| Meanders | Extensive in plains | Less pronounced |
| Delta | Large deltas (Sundarbans) | Deltas (Godavari, Krishna, Kaveri) |
| Drainage | Antecedent and consequent | Superimposed |
Soil Types of India
Indian soils are classified into several major types based on genesis, composition, and distribution.
Major Soil Types and Distribution
| Soil Type | Region/Distribution | Key Properties | Suitable Crops |
|---|---|---|---|
| Alluvial Soil | Indo-Gangetic Plains, river valleys, coastal areas | Rich in potash; deficient in phosphorus and nitrogen; light to dark | Rice, wheat, sugarcane, pulses |
| Black Soil (Regur) | Deccan Plateau (Maharashtra, Gujarat, MP, Karnataka) | Rich in calcium, potassium, magnesium; poor in nitrogen; self-ploughing | Cotton, tobacco, oilseeds, jowar |
| Red Soil | Eastern Deccan, Odisha, Chhattisgarh, Tamil Nadu | High iron content; acidic; poor in nitrogen, phosphorus, humus | Groundnut, red gram, Bengal gram, castor |
| Laterite Soil | Western Ghats, parts of Odisha, Jharkhand, Kerala | Rich in iron and aluminium; acidite; poor in fertility | Tea, coffee, cashew, rubber |
| Arid/Desert Soil | Western Rajasthan, parts of Gujarat, Haryana | Sandy; low humus; high salinity; poor water retention | Bajra, pulses (with irrigation) |
| Forest/Mountain Soil | Himalayan slopes, Western & Eastern Ghats | Rich in humus; acidic; varies with altitude | Tea, coffee, spices, fruits |
| Peaty/Marshy Soil | Kerala, coastal Odisha, Sundarbans, Uttarakhand | High organic content; acidic; waterlogged | Rice (in some areas) |
| Saline/Alkaline Soil | Punjab, Haryana, Rajasthan, coastal Gujarat (Rann of Kutch) | High sodium, potassium, magnesium salts; Usar/Reh | Poor for crops; requires reclamation |
Coastal Plains and Islands
Coastal Plains
| Coast | Name | Length | Features |
|---|---|---|---|
| Western Coast | Konkan, Kanara, Malabar | ~1,500 km | Narrow; rocky; lagoons and backwaters (Kerala); fewer deltas |
| Eastern Coast | Northern Circars, Coromandel | ~2,000 km | Broader; alluvial; lagoon (Chilika Lake); large deltas (Godavari, Krishna, Kaveri) |
Islands
| Island Group | Location | Number | Origin | Key Features |
|---|---|---|---|---|
| Andaman & Nicobar | Bay of Bengal | 572 | Tectonic (submerged mountain chain) | Barren Island (active volcano); dense forests; tribal populations |
| Lakshadweep | Arabian Sea | 36 | Coral origin (atolls) | Small area (~32 sq km); Kavaratti is capital; lagoon-rich |
Important for UPSC
Prelims Focus
- Exact heights of major peaks and lengths of rivers
- Matching rivers with their origin points and tributaries
- Soil types and their crop suitability
- Physiographic divisions and their geological age
- Drainage patterns and their characteristics
- Island groups and their geological origin
Mains Dimensions
- Role of Himalayas in shaping India's climate, rivers, and biodiversity (GS1)
- River interlinking and its geographical, environmental, and social implications (GS1/GS3)
- Soil degradation, conservation strategies, and their link to food security (GS3)
- Peninsular Plateau's mineral wealth and its economic significance (GS1/GS3)
- Coastal zone management and vulnerability to climate change (GS3)
Interview Angles
- Why does India have such diverse physiography in a relatively compact area?
- Should the Himalayas be treated as an ecological entity rather than a political boundary?
- How does the geology of the Peninsular Plateau make it mineral-rich but water-scarce?
- Discuss the strategic significance of the Andaman & Nicobar and Lakshadweep islands.
Previous Year Questions (PYQs)
Prelims
Q. The Brahmaputra, Irrawaddy and Mekong rivers originate in Tibet and flow through narrow and parallel mountain ranges in their upper reaches. Of these rivers, Brahmaputra makes a "U" turn in its course to flow into India. This "U" turn is due to (CSE Prelims 2011) (a) Uplift of folded Himalayan series (b) Syntaxial bending of geologically young Himalayas (c) Geo-tectonic disturbance in the tertiary folded mountain chains (d) Both (a) and (b) above Answer: (b) -- The Brahmaputra's U-turn near Namcha Barwa is caused by syntaxial bending, where the Himalayan ranges sharply bend southward in deep knee-bend flexures at their eastern extremity.
Q. The Narmada river flows to the west, while most other large peninsular rivers flow to the east. Why? (CSE Prelims 2013)
- It occupies a linear rift valley.
- It flows between the Vindhyas and the Satpuras.
- The land slopes to the west from Central India. (a) 1 only (b) 2 and 3 (c) 1 and 3 (d) None of the above Answer: (a) -- The Narmada flows westward because it occupies a linear rift valley formed due to tectonic faulting. Statement 2 is factually correct but not the reason for westward flow. Statement 3 is incorrect as the Deccan Plateau generally slopes eastward.
Q. With reference to the Indus river system, of the following four rivers, three of them pour into one of them which joins the Indus direct. Among the following, which one is such river that joins the Indus direct? (CSE Prelims 2021) (a) Chenab (b) Jhelum (c) Ravi (d) Sutlej Answer: (d) -- The Jhelum and Ravi join the Chenab, and the Beas joins the Sutlej. The Chenab then merges with the Sutlej to form the Panjnad, which joins the Indus directly. The Sutlej is the river into which the others ultimately pour before reaching the Indus.
Q. The black cotton soil of India has been formed due to the weathering of (CSE Prelims 2021) (a) Brown forest soil (b) Fissure volcanic rock (c) Granite and schist (d) Shale and limestone Answer: (b) -- Black soil (regur) is derived from the weathering of Deccan Trap basalt, which is fissure volcanic rock. It is spread across the Deccan Plateau covering parts of Maharashtra, Gujarat, Madhya Pradesh, and Karnataka.
Q. Which of the following statements regarding laterite soils of India are correct? (CSE Prelims 2013)
- They are generally red in colour.
- They are rich in nitrogen and potash.
- They are well-developed in Rajasthan and UP.
- Tapioca and cashew nuts grow well on these soils. (a) 1, 2 and 3 (b) 2, 3 and 4 (c) 1 and 4 (d) 2 and 3 only Answer: (c) -- Laterite soils are red due to high iron oxide content (Statement 1 correct). They are poor in nitrogen, potash, and lime (Statement 2 incorrect). They are found in Western Ghats, Kerala, Odisha, and Jharkhand, not in Rajasthan or UP (Statement 3 incorrect). Tapioca, cashew, tea, and coffee grow well on them (Statement 4 correct).
Mains
Q. "The Himalayas are highly prone to landslides." Discuss the causes and suggest suitable measures of mitigation. (CSE Mains 2016, GS Paper 1, 12.5 marks)
Q. How will the melting of Himalayan glaciers have a far-reaching impact on the water resources of India? (CSE Mains 2020, GS Paper 1, 10 marks)
Q. The interlinking of rivers can provide viable solutions to the multi-dimensional inter-related problems of droughts, floods and interrupted navigation. Critically examine. (CSE Mains 2020, GS Paper 1, 10 marks)
Current Affairs Connect
| Topic Link | Relevance |
|---|---|
| Ujiyari -- Geography News | Latest developments in physical geography, river projects, and geological surveys |
| Ujiyari -- Editorials | Analysis of river interlinking, Himalayan ecology, and coastal erosion policies |
| Ujiyari -- Daily Updates | Daily news on natural disasters, river floods, landslides, and seismic activity |
Sources: Know India -- Physical Features (india.gov.in) | Know India -- Rivers | Know India -- Length of Important Indian Rivers | Central Water Commission -- About Basins | NCERT -- Physical Features of India