Physiographic divisions of India class IX

As per the new text book.
class IX
NCERT

1. PHYSIOGRAPHIC DIVISIONS OF
INDIA
SOCIAL SCIENCE II
GEOGRAPHY AND ECONOMICS
STD IX
BY –ANVESHA KOTIBHASKAR

2. Indiaisacountrywithvariedgeologicaldifferences.Thisvarietyin
geologyhasgivenIndiavariouslandformswhichinturnhasgivenusa
varietyofthings:
Minerals(metallicandnonmetallic
Soils(colour,fertility)
Forests(type,size,shapeetc)
Allthesefactorsareresponsibleforagriculturalproductivityintermsof
varietyofcropsgrowninourcountry.

3. HOW DID INDIA FORM?
1)ContinentalDriftTheory
ProposedbyAlfredWegnerintheyear1912.
Accordingtohimallthecontinentswereoneintheformofone
continentandmegaoceansurroundedit.

4. ThecontinentwasknownasPANGAEA andoceanwas
calledPANTHALASSA .
LaterthecontinentwassplittedintoasEaurasiaand
Gondwanaland(northandsouth)
Eurasia and
Gondwana

5. 2) TECTONIC THEORY
PROPOSED BY Parker and Morgen
There were seven major and several minor plates –African, North
American, South American, Eurasian, Australian, Antarctica, and
Pacific plates.

6. Minor Plates –Arabian, Nazca and Philippine plates.
The tectonic plates composed of two types of lithosphere:
thicker continental and thin oceanic.
The difference in strengths and density between the upper
lithosphere and lower asthenosphere enables the tectonic plates
to move.
Other natural forces like gravity,, earth’s rotation also contribute
to the movement of these plates.

7. The movement of the plates
Plates move in different directions and at varied speeds. The place where
the two plates meet is called plate boundary.
Depending on how the two boundaries move they have following names:
1 Divergent boundary:
2) Convergent boundary
3) Transform boundary.

8. 1 Divergent boundary: the places where two plates move apart. It forms a
valley. Eg. The Narmada Valley

9. 2) Convergent boundary: the places where two plates crash or
crunch together. It leads to the formation of mountains and
plains. Eg. Himalayas and the Great Northern Plains.

10. 3) Transform boundary: the places where two plates move past each
other. They do not tear or crunch each other. Eg. San Andreas
Fault, California.

11. ThearcshapemountainrangesofHimalayas,Hindukushand
Patkaihavesomeofthetallestmountainswhichactasnatural
barrierstothecoldpolarwinds.BecauseofthisIndiahas
developedatropicalmonsoonclimate.

12. CONTINENTAL DRIFT THEORY AND INDIA
Millions of years of ago India and one ocean called the sea of Tethys
were on one plate. The plate began to move northwards.

13. India is divided into the following physiographic divisions:
1)The Northern Mountain
2)The Northern Plains
3)The Peninsular Plateau
4)The Coastal Plains
5)The Indian Deserts
6)The Islands

14. The Northern Mountains
ItisformedbythemountainrangesofKarakoram,Ladakh,Zaskar,The
Himalayas,andtheEasternHighlands.
Theyaresubdividedintothreedivisionsnamely,TransHimalayas,The
Himalayas,andthePurvanchalHills.
1)TheTransHimalayas
ComprisesofKarakoram,LadakhandtheZaskarrangesthatoriginates
fromthePamirKnot.
ThehighestpeakinIndia–MountK2(Mt.GodwinAustin)isinthe
KarakoramRange.

16. 2)TheHimalayas
Theyareconsideredasthehighestmountainrangeintheworld.
Theyareyoungestfoldmountainsandarearcinshape.
TheyconsistofthreeparallelmountainrangesfromNorthtoSouth:
1)ThegreaterHimalays(thenorthernmostrange,theInnerHimalaysor
Himadri)
2)TheMiddleHimalayas(thesouthofGreaterHimalayas,Himachal)
3)TheouterHimalays(southernmostrange,Shiwalik)
3)ThePurvanchal:
Itistheeasternmosthill.
WefindthicklyforestedhillsofKhasiandJaintiaandthewettestspots
likeCherapunjiandMawsynram.

17. TheHimalayanrangesactasanaturalprotectivewallforIndia.
Themountainproviderainwaterfortheplainsbyarrestingthe
moisture-bearingcloudsofthesouth–westmonsoon.
ItprotectsthegreatIndianPlainsfromcoldwindscomingfromthe
polarareas.
ItgivesbirthtothemightyriversliketheIndus,theGanga,the
Brahmaputraandtheirnumeroustributaries.
TheLesserandOuterHimalayasareveryrichinforestandanimals.
ThereareextensiveteagardensintheouterHimalayasinAssamand
thenorthernpartsofwestBengal(Darjeeling)
Tourists,notonlyfromIndiabutothercountiesareattractedtovisit
thesebeautifulplaceshelpingthehoteltourismindustry.
WorldfamousdunsarenoticedintheHimalayanrange.
KashmirValletfamousforitsscenicbeautyliesinHimalays.
BesidesthisBadrinath,Kedarnath,Vaishnodeviarethesacredplaces
intheHimalayas.
IMPORTANCE OF HIMALAYAS

18. TheGreatNorthernPlainsextendoveradistanceof2400kmsinthe
eastwestdirectionand250to320kmsbetweentheHimalayasand
theIndianPlateauinthenorth-southdirection.

19. Thisregionwasformedbyfillingofavastdepressionbythe
siltbroughtdownbytherivers-theIndus,Gangaand
Brahmaputraandtheirtributaries.
Itisdividedintofourrelieffeatures-theBhangar,Khadar,
BhabarandTerai

20. BhangarandKhadar
Thisregionhasrichalluviumsoils-theBhangarandKhadar.
TheBhangarisanuplandformedbythedepositionofolderalluvium.
ItcontainscalcareousdepositsknownasBangar.
Khadarisalowlandformedbythedepositsofnewfineralluvium
whichisrenewedeveryyear.
BhabarandTerai
AtthelowerHimalayanwheretheHimalayasjointheplains,thereare
depositsofcoarsesandandpebblesinawidenarrowbeltformingtwo
sections–BhabarandTerai.
Bhabarlandsarenarrowerintheeastandwiderinthewesternand
north-westernhillyregions.
ThenumeroussmallerstreamsoriginatingontheslopesofShivalik
disappearintheBhabarbelt.
Terai-Tothesouthofthisbelt,theyre-appearandcreateawet,
swampyandmarshyregionknownastheTerai.

22. The Western or Rajasthan Plains
They are also known as the Thar Desert or the Marusthaliof Thar.
This region has several salt lakes like the Sambhar, it is from here that
table salt is obtain.
The lower reaches of Himalayas join the plains wherein there are
deposits of coarse sand and pebbles.
Luniis the largest river in the Thar Desert.
The Indus Plain:
Most of it lies in Pakistan. It is drained by five rivers namely Ravi, Beas,
Chenab, Jhelum & Sutlej and other tributaries.

23. Ganga Plain
The Ganga Plain is formed by the fertile plains between the Ganga
Yamuna rivers.
Brahmaputra Plains
They comprise of the area extending from the foothills of the
Himalaya to the northern parts of Bengal.

24. Importance of Plains
Thegeographicaladvantagesofthisregionisthattheyprovide:
(i)highlyfertilesoil
(ii)favourableclimate
iii.flatlandhelpfulfortheconstructionofroadsandrailways
iv.manyriversforirrigation
v.inlandandwatertransportation.

25. Morethan40percentofthepopulationofIndialivesinthisregion.
ThewesternplainbeyondtheGangaismoreorlessdry.
TotheeastoftheGanga,thesoilisveryfertilethereforeagriculture
remainsthemostindispensableoccupationalactivity.
Therichsoilcovercombinedwiththeabundantwatersupplyand
favourableclimatemakesthisregionahighlyagriculturallyproductive
sectionofIndia.
Thesefactorshavelargelyattractedhumanpopulationtherebymaking
thisregionthedenselypopulatedregionofthecountry.

26. The Peninsular Plateau is the Indian plate from the original
Gondwanaland moved north to form the Himalayas and the Northern
plains.
This plateau forms oldest landmass in India.
It is made up of crystalline, igneous and metamorphic rocks.
The plateau is divided into two broad divisions; Central Highlands and
Deccan Plateau.

28. The Central Highlands cover the area to the north of Narmada river
and includes the MalwaPlateau.
The Aravalihills mark its northwest boundary beyond which it merges
in the Thar Desert of Rajasthan.
The hills of Vindhya outline its southern boundary.
The eastern parts are known as Baghelkhandand Bundelkhand.
The area to its far east is the Chotanagpurplateau which is drained by
the Damodarriver.
The Major north flowing rivers are the Chambal, Betwaand the Ken.
These rivers thereafter drain into the Yamuna.

29. Deccan Plateau
Deccan Plateau is the area to the south of Narmada.
The Satpurarange not only marks its broad base but also forms its
northern boundary.
TheMahadeo,KaimurandMaikalrangesshapeupitseastern
extensions.TheotherthreerangesoftheDeccanPlateauaretheGaro,
KhasiandJaintiahills.
A fault (rock formation) separates the Deccan plateau from the
ChotanagpurPlateau.
To the north and northwest are the highly eroded and broken Aravali
hills.
The Ghats are the distinctive features significant edges of the Deccan
Plateau.

30. The western Ghats
The Western run parallel to the west coast of India. One can cross the
passes like the Thal, Bhorand Pal Ghat.
Western Ghats are known by different regional names such as the
Sahyadriin Maharashtra and Karnataka, the Niligrisin Tamil Nadu,
Anaimalaiand Cardamonhill along the Kerala and Tamil Nadu border.
The highest peak, Anaimudi(2,695 m) is in Kerala.
Kalsubai(1646 m) is the highest peak in the Sahyadris.
Hill stations: Matheran, Mahabaleshwar,Udagamandalam (Ooty) and
Kodaikanal.

31. The Eastern Ghats
TheEasternGhatsextendfromtheMahanadirivervalleyinthenorth
totheNilgirisinthesouth.
TheEasternGhatsarediscontinuousastheyareintervenedbythe
deltasoftheriversoftheDeccanliketheMahanadi,Godavari,Krishna
andKaveri.
ThehighestpeakintheEasternGhatsisMahendragiri(1501m).(Odisha)
TheEasternGhatsandWesternGhatsconvergeintheNilgirihills.(T.N.)
TheDeccanPlateauiscoveredwithitscharacteristicblacksoilknown
astheDeccanTrap.
Itisalsoknownastheblackcottonsoil.
Thissoilisrichinhumusandidealforcottonandsugarcane
cultivation.
Thisregionisrichinmineraldepositsandhasmanysourcesfor
irrigationandgenerationofhydroelectricpower.
Itisalsoendowedwitharichanddiversefloraandfauna.
DodaBeta(2,637m)isthehighestpeakintheNilgirihills

32. The narrow lowlands along the coast of India between the sea and the
eastern and western Ghats form the coastal plains.
The west coast is narrower than the eastern coastal plain.

33. Western Coastal Plain
It is the coastal lowland stretching between the Western Ghats and
the Arabian Sea.
It expands from the Kuchchhin the north to Kanyakumari in the
south.
This coast is known as Konkan in Maharashtra and Goa, Kannada
coast in Karnataka and the Malabar in Kerala.
The west coast has a large number of estuaries, lagoons and
backwaters.
They are noted for spices, areca nuts, coconuts palms, etc.

34. Eastern Coastal Plains
It is the coastal lowland extending from the mouth of Ganga to
Kanyakumari between the Eastern Ghats and the Bay of Bengal .
It is known as Circarsor Kalinga in Northern stretch and as Coromandel
in its southern stretch.
The deltas in the eastern plains are major producers food-grains in the
southern states of Andhra Pradesh, Tamil Nadu, Karnataka, Kerala and
Puducherry.
The coastal plains provide for harboursand well developed fisheries.
Besides having historical significance, this region is also known for the
production specialized crops thereby providing an push to the Indian
economy.

35. The Indian Desert or the Thar Desert' lies along the western margins of
India.
A major part of the desert lies in the state of Rajasthan and extends
into the southern Haryana and Punjab in the north and northern
Gujarat.

36. The desert has the crescent shaped dunes which are called
Barchan.
The region receives less than 150 mm of rain and has an arid
climate with scary vegetation.
River Luniis the only river and it has an inland drainage.

37. The islands can be grouped into two, the Bay of Bengal islands and the
Arabian Sea islands.

38. 1)THE BAY OF BENGAL ISLAND:
These are the Andaman and
Nicobar islands.
They are formed from the
extension of ArakanYoma
mountain and are volcanic in
origin.
They are divided into three
groups; North Andaman, Middle
Andaman and South Andaman.
They are collectively called the
Great Andaman.

39. The passage of water separating the
Little Andaman from the Great
Andamansis known as the Duncan
passage.
Saddle peak is the highest peak in the
Andaman Nicobar islands and Dhuliaris
the highest peak in the Andaman
Islands.
Great Nicobar is the largest and the
southern most island in the Nicobar
group of islands.
Barren Island is a dormant volcano and
NarcondamIsland is an extinct volcano.

40. Arabian Sea Islands
At a distance of about 200 to 300 kms off the coast of Kerala lie a
group of 25 tiny coral islandsknown as Lakshadweep in the Arabian
Sea.
Earlier they were known as Laccadive, Minicoy and Amindivi.
They were named Lakshdweepin the year 1973.
These islands form the smallest Union territory of India. (11miles or
32 sq. kms)

41. The islands in the north are
known as Aminidiviand the
islands in the south are
known as Minicoy Islands.
Minicoy is the largest in
terms of its area.
The main islands are
Kavaratti(the capital) and
Minicoy.
Bitrais the smallest island
and Pitliisland is
uninhabited but has a bird
sanctuary.

42. Geographically Goa has mainly three
natural divisions namely the Lowlands, the
Plateaus and the Mountain region.
1)The Lowlands
2)The Plateau Land (Midland)
3)The Mountain Region

43. 1)The Low lands
The low lands are mainly coastal and about 105 km long. Many
beaches are located along the coast. It stretches from Terekholin
the north to Polemin the south.

44. Plateau Lands (Midland)
The plateau region is found between the mountain region in the east
and the lowlands in the west.
This region comprises of laterite stone which is used for building houses
and other construction work.
Some parts of the plateau are called headlands. A headland is a piece of
land that projects from the coastline into the sea.
Examples of plateaus in Goa are Verna, Kadambaplateau, Bambolim.
Examples of headland are Sada, Cabo de Ram, Aguada.

45. iii) Mountain Region
The Sahyadris, part of the Western Ghats are to the east of South Goa.
This part is covered with dense forest.
In South Goa. the peaks are KatalachiMauli, Sasogad, Chandranathat
Paroda, Dudhsagarin Dharbondarataluka and Karmalghatin Canacona
taluka.
Many streams and rivers flow from this region to lowlands; making the
land fertile and hence thickly populated.