Geography is a high-weightage section across UPSC CSE Prelims and forms a core part of Mains GS Paper I. This module covers physical geography fundamentals (Earth's structure, plate tectonics, rocks, landforms), Indian landforms and soils, the Indian monsoon and climate, Himalayan and Peninsular river systems, world geography (oceans, currents, straits), and natural resources with biodiversity — with every fact, superlative, and numeric detail carried over, plus worked examples and diagrams for each topic.
After studying this chapter you will be able to:
Geography has no strict subject prerequisite, but it connects closely with Environment & Ecology (biodiversity hotspots, protected areas) and Indian Economy (resource distribution, agriculture). Once you've worked through the chapters below, head to the Geography hub page to generate practice tests, or explore Study Material for other UPSC CSE subjects.
Physical geography covers the Earth's structure, landforms, and the processes that shape them. UPSC Prelims tests plate tectonics, types of rocks, earthquake and volcano distribution, and landform terminology.
| Layer | Depth | Composition | State |
|---|---|---|---|
| Crust | 0–35 km (continental) / 0–10 km (oceanic) | Sial (Si + Al) — continental; Sima (Si + Mg) — oceanic | Solid |
| Mantle | 35–2900 km | Silicates of Fe and Mg; Asthenosphere (partially molten) at ~100–300 km | Solid (plastic asthenosphere) |
| Outer Core | 2900–5100 km | Fe and Ni (liquid) | Liquid — generates Earth's magnetic field |
| Inner Core | 5100–6371 km | Fe and Ni (solid — under immense pressure) | Solid |
| Rock Type | Formation | Examples | Key Properties |
|---|---|---|---|
| Igneous | Cooling of magma/lava; no fossils | Granite (intrusive/plutonic), Basalt (extrusive/volcanic), Obsidian, Pumice | Crystalline; forms parent rocks; no fossils |
| Sedimentary | Deposition and lithification of sediments; fossils found here | Sandstone, Limestone, Shale, Coal, Conglomerate | Layered (stratified); fossils; most common at surface |
| Metamorphic | Heat + pressure transforms existing rocks | Marble (from limestone), Slate (from shale), Quartzite (from sandstone), Schist, Gneiss | Banded/foliated; harder than parent rock |
| Process | Type | Example Landforms |
|---|---|---|
| River/Fluvial erosion | Exogenic | V-valley, gorge, waterfall, meander, oxbow lake, delta, floodplain |
| Glacial erosion | Exogenic | U-valley, cirque (corrie), arête, horn, fjord, hanging valley, drumlin (deposition) |
| Wind/Aeolian | Exogenic | Sand dunes (Barchan — crescent shaped), deflation hollows, mushroom rocks, yardangs |
| Coastal | Exogenic | Sea cave, stack, arch, wave-cut platform, beach, spit, lagoon |
| Karst (limestone) | Exogenic | Stalactite (ceiling), stalagmite (floor), limestone pavement, sink holes, caves |
Logarithmic; 1 unit = 10× ground motion
Crust 0–35 km; Mantle 35–2900 km; Outer Core 2900–5100 km; Inner Core 5100–6371 km
P-waves (fastest) > S-waves > Surface waves (slowest, most destructive)
~75% of world's volcanoes; Pacific rim
Given: One earthquake measures 6.0 on the Richter scale, another measures 4.0. How many times greater is the ground motion of the magnitude-6.0 quake?
Solution: The Richter scale is logarithmic, so each whole-number increase means 10× more ground motion. The difference here is 2 units.
\( 10^2 = 100 \)
Answer: The magnitude-6.0 earthquake has 100 times greater ground motion than the magnitude-4.0 quake.
Given: Two continental plates collide head-on, causing the crust to fold and thicken into towering mountains with no oceanic trench formed. Which type of plate boundary is this, and what landform results?
Solution: Since both plates are continental (neither is dense enough to subduct), collision produces folding rather than subduction — exactly how the Himalayas formed from the Indian and Eurasian plates.
Answer: Convergent boundary (continental-continental collision) — produces fold mountains like the Himalayas.
Given: A rock shows clear banding, is harder than its parent material, and formed when limestone was subjected to intense heat and pressure. Classify this rock and name it.
Solution: Banding/foliation and formation via heat-and-pressure transformation of an existing rock are hallmarks of metamorphic rock; limestone specifically metamorphoses into marble.
Answer: Metamorphic rock — specifically marble, formed from limestone.
Fig. 1.1 — Earth's internal structure: solid Crust and Mantle surround the liquid Outer Core (which generates the magnetic field) and the solid, pressure-compacted Inner Core.
India's physical geography includes the Himalayan mountains, Indo-Gangetic Plains, Peninsular Plateau, Coastal Plains, and Islands. UPSC tests the classification of Himalayas, river systems, and geographical terminology specific to India.
| Division | Sub-divisions / Key Facts |
|---|---|
| The Himalayan Mountains | Trans-Himalayas (Karakoram, Ladakh range, Zaskar); Greater Himalayas (Himadri — highest, permanent snow); Lesser Himalayas (Himachal — Mussoorie, Shimla, Nainital); Outer Himalayas (Shivaliks — terai zone at foot) |
| The Northern Plains | Bhabar (pebble belt below Shivaliks); Terai (marshy forest); Bhangar (old alluvium, higher); Khadar (new alluvium, lower, fertile, flood-prone) |
| The Peninsular Plateau | Deccan Plateau (basalt, black cotton soil); Central Highlands (Malwa, Chota Nagpur); Eastern Ghats (discontinuous, lower — avg 600m); Western Ghats (continuous, higher — avg 1000m; highest: Anamudi 2695m) |
| The Coastal Plains | Western: narrow, straight, steep (Konkan, Malabar); Eastern: wider, deltaic, flat (Coromandel/Carnatic, Northern Circars) |
| The Islands | Andaman & Nicobar (Bay of Bengal — 572 islands; volcanic origin; largest = Great Andaman); Lakshadweep (Arabian Sea — coral; 36 islands; smallest UT) |
| Pass | Location | Connects |
|---|---|---|
| Khyber Pass | Afghanistan–Pakistan border | Afghanistan to Pakistan (historical invasion route) |
| Bolan Pass | Pakistan (Balochistan) | Pakistan to Afghanistan |
| Rohtang Pass | Himachal Pradesh | Kullu–Lahaul-Spiti; NH-3; Atal Tunnel bypass now |
| Nathu La | Sikkim–Tibet border | India–China trade; 4310m; reopened 2006 |
| Shipki La | Himachal Pradesh–Tibet | Sutlej river enters India; India–China border |
| Lipulekh | Uttarakhand–Tibet | Kailash Mansarovar yatra route |
| Zoji La | J&K (Kashmir–Ladakh) | NH-1D; Srinagar to Leh |
| Soil Type | Region | Formed From | Crop Suitability |
|---|---|---|---|
| Alluvial | Northern plains, river deltas | River deposits | Most fertile; wheat, rice, sugarcane, pulses |
| Black (Regur) | Deccan Plateau — Maharashtra, MP, Gujarat | Basalt lava weathering | Cotton, sorghum, oilseeds; self-ploughing (swells/shrinks) |
| Red | Tamil Nadu, Andhra, Odisha, Chhattisgarh | Crystalline/metamorphic rock | Coarse grains, groundnut; red due to iron oxide |
| Laterite | High rainfall areas — Kerala, Karnataka, NE India, Odisha | Leaching of silica; iron/aluminium oxides remain | Tea, coffee, cashew; low fertility; hardened when dry |
| Desert/Arid | Rajasthan, Gujarat | Wind deposits | Drought-resistant crops; low organic matter |
| Mountain/Forest | Himalayas, NE India, Western Ghats | Decomposed organic matter | Tea, spices, fruit; acidic |
Western: continuous, avg 1000m; Eastern: discontinuous, avg 600m
2695 m — highest peak in Peninsular India
Bhangar = old alluvium, higher; Khadar = new alluvium, lower, more fertile
A&N: 572 islands, volcanic; Lakshadweep: 36 islands, coral
Given: A range contains hill stations like Shimla, Mussoorie, and Nainital, sitting between the highest snow-capped range and the outermost foothill range. Identify it.
Solution: This description matches the middle tier of the Himalayan system — lower than the Greater Himalayas but higher than the Shivaliks.
Answer: The Lesser Himalayas (Himachal range).
Given: A farmer's field floods every monsoon and receives fresh silt each year, making it especially fertile. Which alluvial soil type is this, and how does it differ from the other type found in the Northern Plains?
Solution: Fields that flood annually and receive fresh sediment are Khadar (new alluvium), found in lower-lying areas; Bhangar (old alluvium) sits on higher terraces and does not flood regularly.
Answer: Khadar — newer, lower, more fertile than Bhangar.
Given: Which mountain pass is used for the Kailash Mansarovar Yatra pilgrimage route into Tibet?
Solution: Among India's Himalayan passes, Lipulekh (Uttarakhand–Tibet) is specifically associated with this pilgrimage route.
Answer: Lipulekh Pass.
Fig. 2.1 — The four Himalayan sub-ranges by elevation: Outer (Shivalik), Lesser (Himachal), Greater (Himadri, highest, permanent snow), and Trans-Himalaya (Karakoram/Ladakh).
India has a monsoon-dominated climate with significant regional variation. UPSC tests the mechanism of Indian Monsoon, factors affecting climate, Köppen classification, and causes of El Niño/La Niña.
| Region | Annual Rainfall | Reason |
|---|---|---|
| Cherrapunji/Mawsynram (Meghalaya) | > 1100 cm (highest) | Funnel-shaped terrain; Bay of Bengal branch concentrated |
| Western Ghats (windward) | 200–400 cm | Orographic rainfall |
| Deccan Plateau (leeward) | 50–100 cm | Rain shadow — drier |
| Rajasthan / Thar Desert | < 25 cm (lowest) | Far from moisture source; Aravalli range parallel to winds |
| Western Himalayas (J&K) | Winter rainfall from Western Disturbances (not monsoon) | Mediterranean depressions |
| Tamil Nadu (SE coast) | Receives rainfall in October–December | Northeast (retreating) Monsoon |
| Type | Region in India | Characteristics |
|---|---|---|
| Tropical Rainforest (Af) | Kerala, Andaman Islands | No dry season; >60 mm rain every month |
| Tropical Monsoon (Am) | Western coastal India | Heavy seasonal rain; short dry season |
| Tropical Savanna (Aw) | Interior Peninsular India | Dry winter; wet summer |
| Semi-Arid (BSh) | Rajasthan fringe, Deccan | Steppe; insufficient rain |
| Arid (BWh) | Thar Desert (Rajasthan) | Desert; very low rainfall |
| Humid Subtropical (Cwa) | North/NE India | Dry winter; hot wet summer |
| Mountain/Alpine (H) | Himalayas | Altitude controls temperature |
Intense low-pressure systems that form over warm tropical oceans (sea-surface temperature > ~26.5 °C) with a warm, calm central eye surrounded by the eyewall of the strongest winds. They are called cyclones in the Indian Ocean, hurricanes in the Atlantic and typhoons in the NW Pacific.
Kerala ~1 June → NW India late June/July → all India by mid-July
~75% of India's annual rainfall (June–September)
Mawsynram >1100 cm (highest); Thar Desert <25 cm (lowest)
Irregular, recurs every 2–7 years
Given: Monsoon onset in Kerala is around 1 June; onset in Delhi (NW India) is around late June to early July. Roughly how many weeks does the monsoon take to progress from Kerala to Delhi?
Solution: From 1 June to early July spans roughly four to five weeks.
Answer: Approximately 4–5 weeks for the monsoon to advance from Kerala to Delhi.
Given: The Deccan Plateau receives only 50–100 cm of rainfall despite being close to the Arabian Sea monsoon source, while the adjacent Western Ghats receive 200–400 cm. Explain this contrast.
Solution: The Western Ghats intercept moisture-laden winds and force them to rise (orographic rainfall), depositing most of the moisture on the windward (western) slope; the Deccan Plateau lies on the leeward side, in the resulting rain shadow.
Answer: The Deccan Plateau lies in the rain shadow of the Western Ghats, which strip most of the moisture from the monsoon winds before they descend eastward.
Given: In a particular year, the central-eastern Pacific Ocean is significantly warmer than average, and India experiences below-normal monsoon rainfall. Identify the phenomenon and its typical mechanism.
Solution: Warming of the central-eastern Pacific is the defining feature of El Niño, which weakens trade winds and is associated with reduced Indian monsoon rainfall.
Answer: El Niño — its warming weakens trade winds and typically suppresses the Indian monsoon.
Fig. 3.1 — The two monsoon branches: the Arabian Sea branch strikes Kerala first, the Bay of Bengal branch strikes the Andamans first and curves west, and both merge to cover all of India by mid-July.
India has two distinct river systems — Himalayan (perennial, snowfed) and Peninsular (seasonal, rain-fed). UPSC tests tributaries, drainage basins, important lakes, and Ramsar Wetlands.
| River System | Origin | Key Tributaries | Drains Into |
|---|---|---|---|
| Indus | Mansarovar (Tibet); enters India at Ladakh | Jhelum, Chenab, Ravi, Beas, Sutlej (5 rivers of Punjab) | Arabian Sea |
| Ganga | Gangotri glacier (Bhagirathi); meets Alaknanda at Devprayag | Yamuna, Ramganga, Kosi, Gandak, Ghaghra, Son | Bay of Bengal (Sundarban delta) |
| Brahmaputra | Chemayungdung glacier (Tibet) as Tsangpo; enters India at Arunachal as Dihang | Dibang, Lohit, Tista, Subansiri | Bay of Bengal (world's largest delta with Ganga) |
| River | Origin | Direction | Drains Into |
|---|---|---|---|
| Mahanadi | Chhattisgarh (Raipur dist.) | East | Bay of Bengal; Hirakud Dam |
| Godavari | Nasik (Maharashtra) | East | Bay of Bengal; longest Peninsular river |
| Krishna | Mahabaleshwar (Western Ghats) | East | Bay of Bengal; Nagarjuna Sagar Dam |
| Kaveri | Coorg/Kodagu (Karnataka) | East | Bay of Bengal; Mettur Dam; dispute between Karnataka–TN |
| Narmada | Amarkantak Plateau (MP) | West | Arabian Sea; flows through rift valley; Sardar Sarovar Dam |
| Tapti/Tapi | Satpura Range (Betul, MP) | West | Arabian Sea; flows through rift valley |
| Luni | Aravalli (near Pushkar) | Southwest | Rann of Kutch; saline in lower course |
| Lake | State | Type | Key Fact |
|---|---|---|---|
| Wular Lake | J&K | Freshwater (tectonic) | Largest freshwater lake in India |
| Dal Lake | J&K | Freshwater | Famous for houseboats; Srinagar |
| Chilika Lake | Odisha | Saltwater lagoon | Largest brackish water lagoon in Asia; Ramsar site; Irrawaddy dolphins |
| Kolleru Lake | Andhra Pradesh | Freshwater | Largest freshwater lake in South India; Ramsar site |
| Sambhar Lake | Rajasthan | Saline (inland) | Largest saline lake in India; salt production; migratory flamingos |
| Loktak Lake | Manipur | Freshwater | Largest freshwater lake in NE India; floating islands (phumdis); Keibul Lamjao NP |
| Vembanad Lake | Kerala | Lagoon | Longest lake in India; Ramsar site; Kuttanad below sea level farming |
| Pangong Tso | Ladakh (India–China) | Saline (high altitude) | Spans LAC; 3 Idiots film; ~60% in China |
Himalayan: perennial, snow-fed; Peninsular: seasonal, rain-fed
Narmada & Tapti flow west via rift valleys
Longest Peninsular river; "Dakshin Ganga"
75+ (2023); first two (1981): Chilika + Keoladeo
Given: A Peninsular river originates at the Amarkantak Plateau in Madhya Pradesh and flows west through a rift valley to the Arabian Sea, unlike most Peninsular rivers. Identify it.
Solution: Most Peninsular rivers flow east to the Bay of Bengal; only Narmada and Tapti are prominent exceptions flowing west through rift valleys — Amarkantak specifically is Narmada's origin.
Answer: Narmada.
Given: One river remains full of water year-round even in peak summer, fed by melting glaciers; another river nearly dries up outside the monsoon season. Classify each river system.
Solution: Perennial, glacier-fed flow year-round regardless of season — characteristic of Himalayan rivers; rivers that depend on seasonal rainfall and nearly dry up in summer are Peninsular rivers.
Answer: The perennial glacier-fed river is Himalayan; the seasonal, rain-dependent river is Peninsular.
Given: Which lake holds the record for the largest brackish water lagoon in Asia, and where is it located?
Solution: Chilika Lake in Odisha is specifically recognised as Asia's largest brackish water lagoon and is also a Ramsar site.
Answer: Chilika Lake, Odisha.
Fig. 4.1 — Himalayan rivers (perennial, snow-fed) versus Peninsular rivers (seasonal, rain-fed): the two fundamentally different river systems of India.
World Geography covers continents, oceans, latitudes, longitudes, ocean currents, and major geographical features. UPSC tests locations, superlatives, and economic/political geography of world regions.
| Feature | Name | Location |
|---|---|---|
| Largest continent | Asia | ~44.6 million km² |
| Largest ocean | Pacific Ocean | ~165 million km² |
| Largest country (area) | Russia | 17.1 million km² |
| Longest river | Nile (disputed with Amazon) | Africa; ~6650 km |
| Highest mountain | Mt Everest (8848.86m) | Nepal–China border (Sagarmatha) |
| Deepest ocean trench | Mariana Trench (11,034m) | Western Pacific |
| Largest desert | Antarctic Desert | Antarctica (Sahara = largest hot desert) |
| Largest lake | Caspian Sea | Landlocked — Eurasia |
| Deepest lake | Lake Baikal | Russia; ~1642m deep; 20% world freshwater |
| Largest island | Greenland | North Atlantic (Australia is a continent) |
| Current | Ocean | Type | Effect |
|---|---|---|---|
| Gulf Stream | Atlantic | Warm | Warms NW Europe; enables mild climate |
| Labrador Current | Atlantic | Cold | Cools NE Canada; Grand Banks fog + fishing |
| Humboldt/Peru Current | Pacific (South America) | Cold | Driest desert (Atacama) on coast; rich fishing until El Niño |
| Kuroshio Current | Pacific | Warm | Warms Japan's eastern coast; Japan's "Black Current" |
| Canary Current | Atlantic (Africa) | Cold | Contributes to Sahara and Namib desert formation |
| North Atlantic Drift | Atlantic | Warm | Extension of Gulf Stream; keeps North Sea ports ice-free |
| Benguela Current | South Atlantic (Africa) | Cold | Contributes to Namib Desert |
| Strait / Channel | Connects | Location |
|---|---|---|
| Strait of Hormuz | Persian Gulf – Arabian Sea | Iran–Oman; critical oil transit chokepoint |
| Strait of Malacca | Indian Ocean – South China Sea | Between Malaysia and Indonesia; busiest maritime chokepoint |
| Bab-el-Mandeb | Red Sea – Gulf of Aden | Yemen–Djibouti; near Suez Canal route |
| Strait of Gibraltar | Atlantic – Mediterranean | Spain–Morocco |
| Palk Strait | Bay of Bengal – Palk Bay | India–Sri Lanka; Adam's Bridge |
| 10° Channel | Andaman Sea – Bay of Bengal | Between Little Andaman and Nicobar Islands |
| 8° Channel / Minicoy | Arabian Sea | Between Lakshadweep and Minicoy; India exclusive |
Economic activities are grouped into primary (extraction — agriculture, mining, fishing, forestry), secondary (manufacturing/industry), and tertiary (services — trade, transport, finance, IT). Their location is shaped by different factors:
Example: India's iron-and-steel plants (Jamshedpur, Bhilai, Rourkela, Bokaro) cluster in the Chhotanagpur plateau near coal + iron ore; the software/IT services sector concentrates in Bengaluru, Hyderabad and Pune (skilled labour + connectivity, not raw material).
8848.86 m — world's highest mountain
11,034 m — world's deepest oceanic trench
~20% of world oil trade transits through it
~1642 m deep; holds ~20% of world's freshwater
Given: A current off the coast of South America keeps the adjacent Atacama Desert extremely dry and supports rich fishing grounds, except during El Niño years. Identify this current and its temperature type.
Solution: The Humboldt (Peru) Current runs along South America's Pacific coast, and being a cold current, it suppresses rainfall along the adjacent coast while supporting nutrient-rich upwelling for fisheries.
Answer: Humboldt (Peru) Current — a cold current.
Given: Which strait connects the Indian Ocean to the South China Sea and is considered the world's busiest maritime chokepoint?
Solution: Located between Malaysia and Indonesia, this strait carries the highest volume of global shipping traffic of any strait.
Answer: Strait of Malacca.
Given: Distinguish the world's largest island from the world's largest continent-sized landmass, and explain why Australia is classified differently from Greenland.
Solution: Greenland, despite its large size, is geologically and tectonically part of a continental plate but not itself classified as a continent — it remains the world's largest island. Australia, though comparable in some ways, is classified as its own continent due to its distinct tectonic plate and biogeography.
Answer: Greenland = largest island; Australia is classified as a continent, not an island, despite the size comparison.
Fig. 5.1 — Warm ocean currents (e.g. Gulf Stream) moderate coastal climates, while cold currents (e.g. Humboldt, Benguela) cool coasts and often create adjacent coastal deserts.
India is among the world's 17 megadiverse countries. UPSC tests forest types, biodiversity hotspots, national parks, and natural resources distribution — especially minerals and energy.
| Forest Type | Rainfall | Region | Key Species |
|---|---|---|---|
| Tropical Evergreen | >200 cm | Western Ghats, Andamans, NE India | Rosewood, Mahogany, Ebony; trees never shed all leaves together |
| Tropical Deciduous (Monsoon) | 100–200 cm | Most of India; MP, UP, Bihar | Teak, Sal, Sandalwood; shed leaves in dry season |
| Tropical Dry Deciduous | 75–100 cm | Eastern UP, Rajasthan fringe | Teak, Acacias, Tendu |
| Tropical Thorn/Scrub | <75 cm | Rajasthan, Gujarat, Punjab plains | Babul, Cactus, Khejri; thorny; xerophytic |
| Mangrove | Coastal, tidal zones | Sundarbans (largest), Bhitarkanika, Pichavaram | Sundari tree (Sundarbans named after it); Rhizophora; salt-tolerant |
| Alpine / Montane | High altitude | Himalayas >3600m | Coniferous below snowline; grassland (bugyals) above; rhododendron |
| Protected Area | State | Known For |
|---|---|---|
| Kaziranga NP | Assam | Indian one-horned rhinoceros (~70% of world pop); UNESCO WHS; tigers |
| Sundarbans NP | West Bengal | Bengal Tiger; world's largest mangrove; UNESCO WHS; Irrawaddy dolphins |
| Gir NP | Gujarat | Asiatic Lions (only wild population outside Africa) |
| Periyar NP | Kerala | Elephants; tiger reserve; Western Ghats |
| Bharatpur (Keoladeo) | Rajasthan | Migratory birds; UNESCO WHS; Siberian Cranes (rare) |
| Valley of Flowers | Uttarakhand | Alpine meadows; UNESCO WHS; endemic flora |
| Manas NP | Assam | Royal Bengal Tiger; Golden Langur; UNESCO WHS; Project Elephant |
| Namdapha NP | Arunachal Pradesh | All 4 big cats of India (tiger, leopard, snow leopard, clouded leopard) |
Evergreen >200cm; Deciduous 100–200cm; Dry Deciduous 75–100cm; Thorn/Scrub <75cm
4 of the world's 36 hotspots
1973; 54 reserves; ~70% of world's wild tigers; ~3167 (2022)
India's first national park (1936); first tiger reserve
Given: A region receives 150 cm of annual rainfall, and its dominant trees (teak, sal) shed their leaves in the dry season. Classify this vegetation type.
Solution: 150 cm falls within the 100–200 cm range, and leaf-shedding in the dry season is characteristic of deciduous (not evergreen) forest.
Answer: Tropical Deciduous (Monsoon) Forest.
Given: Name the four global biodiversity hotspots that overlap with Indian territory.
Solution: These are defined by high endemism and habitat loss criteria (Norman Myers), and India's portions span both mainland and island territories.
Answer: Western Ghats & Sri Lanka, Indo-Burma, Eastern Himalayas, and Sundaland (Andaman & Nicobar Islands).
Given: Which national park is the sole wild habitat of the Asiatic Lion outside Africa?
Solution: Gir National Park in Gujarat is the only place in the world (besides zoos) where wild Asiatic Lions survive.
Answer: Gir National Park, Gujarat.
Fig. 6.1 — India's vegetation zones ordered by decreasing rainfall: Tropical Evergreen (>200cm), Deciduous (100–200cm), Dry Deciduous (75–100cm), and Thorn/Scrub (<75cm).
Highest peak in Peninsular India (2695m) — Kerala (Western Ghats)
Second highest peak in world (8611m); highest in India; Karakoram
Largest freshwater lake in India (J&K); tectonic origin
Largest brackish water lagoon in Asia (Odisha); Ramsar site
Largest saline lake in India (Rajasthan)
Largest freshwater lake in NE India (Manipur); floating islands = phumdis
Highest average annual rainfall (Meghalaya)
Lowest rainfall in India (<25 cm)
~1 June (Arabian Sea branch)
Tamil Nadu gets Oct–Dec rainfall from retreating monsoon
Flows west through rift valley → Arabian Sea
Longest Peninsular river; "Dakshin Ganga"; originates Nasik
Called Tsangpo; enters India as Dihang (Arunachal)
75+ (2023); most in Asia; first two (1981) = Chilika and Keoladeo
~20% world oil passes; Iran–Oman
Busiest maritime chokepoint; Malaysia–Indonesia
Crescent-shaped wind dune
4: Western Ghats+SL, Indo-Burma, E. Himalayas, Sundaland
Only wild Asiatic Lions — Gujarat
India's first national park (1936) — Uttarakhand
1973; 54 tiger reserves; ~3167 tigers (2022)
Weakens monsoon; drought tendency
Sundarbans (West Bengal)
| Topic | Prelims Focus | Mains GS-I Focus |
|---|---|---|
| Physical Geography | Earth layer facts; rock/landform terminology | Geomorphic processes shaping India's terrain |
| Indian Landforms | Physiographic divisions; soil-region matching | Regional development linked to landform/soil |
| Climate & Monsoon | Onset dates; rainfall figures; El Niño/La Niña | Monsoon variability and agricultural impact |
| Rivers & Water Bodies | Origin-tributary-mouth matching; lake superlatives | Inter-state river disputes; water resource management |
| World Geography | Superlatives; strait/chokepoint facts | Geopolitics of straits and maritime trade routes |
| Natural Resources | Forest type-rainfall matching; hotspot facts | Conservation vs development trade-offs |
Q1. One earthquake measures 6.0 on the Richter scale, another measures 4.0. How many times greater is the ground motion of the magnitude-6.0 quake?
Q2. Monsoon onset in Kerala is ~1 June; onset in Delhi is ~late June/early July. Roughly how many weeks does the monsoon take to progress from Kerala to Delhi?
Q3. A Peninsular river flows west through a rift valley to the Arabian Sea, originating at the Amarkantak Plateau. Name it.
Q4. India has 75+ Ramsar sites today; the first two were designated in 1981. Roughly how many sites has India added since 1981?
Q5. A wind-formed, crescent-shaped sand dune found in deserts is called what landform?