Physical Features of India - GEO CLASS 9

Himalayas

  • young fold mountains, northern border, Indus → Bramhaputra

  • 2400km arc

  • width - 150km(arunanchal) to 400km(kashmir)

  • greater height variation in east

  • duns(valleys between himachal, shiwalik) - dehradun, kotli dun, patli dun

  • sharp southward turn from dihang gorge, spread along eastern border

himadri/greater/inner himalayas

  • continuous, 6000m, asymmetrical, granite, perennial snow

  • mt. everest - 8848m, kanchenjunga - 8598, makalu - 8481

himachal / lesser himalayas

  • rugged, compressed rocks

  • 3700-4500m, 50km width

  • Pir Panjal(longest), Dhaula Dhar, Mahabharat

  • valley of Kashmir, Kangra and Kullu Valleyrugged, compressed rocks

  • 3700-4500m, 50km width

  • Pir Panjal(longest), Dhaula Dhar, Mahabharat

  • valley of Kashmir, Kangra and Kullu Valleyrugged, compressed rocks

  • 3700-4500m, 50km width

  • Pir Panjal(longest), Dhaula Dhar, Mahabharat

  • valley of Kashmir, Kangra and Kullu Valley

shiwalik

  • 900-1100m, 10-50km width

  • unconsolidated sediments brought from rivers from main himalayas

  • covered with gravel, aluminium

purvanchal

  • strong sandstone, densely forested, parallel ranges

  • patkai hills, naga hills, manipur hills, mizo hills

Northern Plains

indus, ganga, brahmaputra

formed from alluvium deposition at foothills of himalayas

7 lakh km² - 2400km length, 240-320km breadth

densely populated

majauli (bramhaputra) - largest inhabited riverine island

lower course

  • slow down due to gentler course, form riverine islands

  • split into distributaries (due to silt)

sections (west to east)

punjab plain

pakistan, indus, doabs

ganga plain

  • ghaggar to teesta rivers

  • north india, haryana, delhi, up, bihar, jharkhand, wb

bramhaputra plain (assam)

regions(north to south)

  • bhabar - width - 8 to 16km, parallel to shiwalik, rivers deposit pebbles, disappear

  • terai - streams reappear, swamp, thick forest cut for migrants after partition

  • bhangar - old alluvium, terrace-like, kankar

  • khadar - renewed every year, intensive agriculture

  • real old, tableland, rounded hills

  • crystalline / igneous / metamorphic rocks, formed from drifting of Gondwana land

  • full of minerals, boosted industrialisation

  • real old, tableland, rounded hills

  • crystalline / igneous / metamorphic rocks, formed from drifting of Gondwana land

  • full of minerals, boosted industrialisation

  • real old, tableland, rounded hills

  • crystalline / igneous / metamorphic rocks, formed from drifting of Gondwana land

  • full of minerals, boosted industrialisation

Peninsular Plaeau

  • real old, tableland, rounded hills

  • crystalline / igneous / metamorphic rocks, formed from drifting of Gondwana land

  • full of minerals, boosted industrialisation

Central Highlands

  • north of narmada

  • covers malwa plateau

  • vindhya bounded by satpura on south, aravali on northwest

  • western extension merges with rajasthan desert

  • rivers flow southwest to northeast- chambal, sind, betwa, ken

  • wider in west

  • eastward extension - bundelkhand, baghelkhan (even more east → chhotanagpur(drained by damodar))

Western Ghats

  • parallel to western coast

  • continuous

  • thal, bhor, pal ghats

  • 900-1600m, height increases north to south

  • orographic rain- moist winds rise along its slope

  • anai mudi(2,695m), doda betta(2,637m)

Eastern Ghats

  • dissected by rivers draining into BoB (not continuous)

  • 600m

  • mahanadi valley(north) to nilgiris(south)

  • highest peak - mahendragiri(1,501m)

  • southeastern extension - shevroy hills, javadi hills

  • ooty = kodaikanal = udagamandalam

Deccan Plateau

  • inverted triangle, satpura as base

  • eastern extension - mahadev, kaimur hills, maikal range

  • higher in west

  • northeastern extension - meghalaya, karbi-anglong plateau, north cachar hills

  • separated from chhotanagpur by a fault

  • hill ranges(west to east) - Garo, Khasi, Jaintia

deccan trap - black soil region made from igneous rocks(volcanic)

aravali hills - northern, northwestern boundary, ‘broken hills’, gujarat(southwest) to delhi(northeast)

aravali hills - northern, northwestern boundary, ‘broken hills’, gujarat(southwest) to delhi(northeast)

Indian Desert

  • western margin of aravali

  • sandy plain, sand dune, 150mm rainfall, arid, streams only in monsoon, luni river

  • barchans(crescent-shaped dunes), longitudinal dunes near indo-pak

Coastal plains (narrow strips)

western coast (north to south)

  • konkan (mumbai-goa)

  • kannad plain

  • malabar coast

eastern coast (north to south)

  • northern circar

  • coromandel coast

  • mahanadi, godavari, krishna, kaveri rivers form deltas

  • lake chilika(odisha) - largest saltwater lake in india

Islands

lakshadweep

  • coral island, 32 km², kavaratti island(hq), pitti island(bird sanctuary)

  • laccaadive, minicoy and amindive- renamed in 1973

andaman and nicobar

  • bigger, more scattered

  • andaman(north), nicobar(south)

  • elevated portion of submarine himalayas

  • densely forested

  • barren island - india’s only active volcano