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Himalaya/Plain and Plateaus/Coastal Plain and Islands

Himalayan Physiography Northern Plains, Plateaus and Desert Coastal Plains and Islands

Himalayan Physiography

India is the seventh largest in terms of area (32, 87,263 km2) and second most populous country in the world accounting for about 2.4% of the total world area. It lies in the northern hemisphere between the 8 degree 4’ N and 37 degree 6’ N parallel of latitude and the 68 degree 7’ E and 97 degree 25’ E meridians of longitude, and is a part of the Asian Continent.

•    The peninsular part of the India extends itself into the Indian Ocean dividing it into the Arabian Sea and the Bay of Bengal.
•    In the oceanic and sea water India claims a 12 nautical mile of territorial waters and an exclusive economic zone of 200 nautical miles.
•    India has accounted to 6,100 km. of mainland coastline and total including island is 7,516.6 km.
•    India shares total of 15,200 km. land frontier with six nations those are: Pakistan (3,310 km), China (3,917 km), Nepal (1,752 km), Bhutan ( 587 km), Bangladesh ( 4,096 km) and Myanmar (1,458 km).
•    India’s total land mass is divided into four main geological featured regions as, northern mountains, northern plains, peninsular region and coastal plains.

NORTHERN MOUNTAIN COMPLEX (HIMALAYA):
•    This is among the youngest mountain ranges on the planet and highest mountain range in the world which separating the Indian subcontinent from the Tibetan Plateau.
•    It is the source of two of the world’s major river systems- the Indus basin and the Ganga-Brahmaputra Basin.
•    This range is divided into:

A.    The Himalayas:
•    The central axial length of the Himalayas is about 2400 km. from Nanga Parbat in the west to Namcha  Barwa  in  the  east.
•    Himalayan  ranges  are considered  extension  of  the  trans-Eurasian  mountain  ranges  and  Pamir  knot (roof of the world) is  the  connecting  link  between these ranges.
•    It  is  estimated  that  the  Indian  plate  is  still  moving northward  at  a  rate  of  about  5cm.  per year.
•    This is not a single range but series of chain of mountains. Suleman, kirthar, kulung shang, Tian sang, Arkanyoma , Pegayoma are the well known mountain ranges situated in this mountain.

North- south division of Himalayas
–    Great Himalayas (Himadri)
–    Middle/ Lesser Himalayas (Himachal)
–    Shivalik (outer Himalayas)




East-West division of Himalayas
Western Himalaya:
•    Its extent is  about  880  km  between  the  Indus  in  the  west  and  the  Kali  river  in the  east.  The western Himalayas  spread  in  three  states  of  Jammu  and  Kashmir Himalaya,  Himachal Himalaya,  and  Kumaon  Himalayas,  respectively.
•    The northern slopes are gentler and are bare  and show plains with lakes, while the southern  slopes are  rugged and forested. Zojila, Rohtang, Bara Lacha la and Shipki La are important passes.
•    This area has the beautiful valleys of Kullu, Kangra and Lahul and Spiti.

Central Himalaya:
•    It  stretches  between  the  river  Kali  in  the  west  and  river  Tista  in  the  east  for  a  distance  of  about  800  km.
•    It lies mainly in the Nepal. All the three ranges of the Himalayas are present here.
•    The great Himalayas attain maximum height here. Yepokangara, Lidanda, Chuuling, Annapurna, Mayondi are glaciers are present in this region.

Eastern Himalaya:
•    This lies between the Tista river in the west and the Brahmaputra river in the east.
•    Its extent is about 720 km. It occupies mainly the areas of Arunachal Pradesh and Bhutan.
•    Important  mountain passes are Zelap la, Bum la, Tse la, Tunga, Yonggypa and Kengri Karpo la.
•    In this region of Himalayas, due to heavy rain fall by south west monsoon and north east causes heavy fluvial erosion.
•    The  Himalayas  take  a  knee  bend  southward  turn  beyond  Dihang  george,  running  more  or  less  along  India’s border with Myanmar known as Purvanchal Hills.
•    Locally they are known as Patkai Bum, Naga Hills, Kohima Hills,  Manipur  Hills,  Mizo  Hills  (Lushai  Hills),  Tripura  Hills  and  Barail  ranges.


B.    Trans Himalayan mountain region or Tibetans Himalayan Region:
This region is located to the north of the great Himalayas which is consists of Karakoram, ladakh, zhaskar and kailash mountain range. It is also called the Tibetans Himalayan region because most of the part of this range lies in the Tibet. The Karakoram range is known as ‘backbone of high Asia’. K2 is the second highest pick in the world and highest in the Indian Territory.

C.    Eastern Hills or the Purvanchal Hills  
After crossing the Dihang gorge (Brahmaputra gorge), the Himalayas Suddenly turn southward and form a series of comparatively low hills running in the shape of a crescent with its convex side pointing towards the west.

These hills are collectively called the Purvanchal because they are located in the eastern part of the country. It extends from Arunachal Pradesh in the north to Mizoram in the south and form boundary between India and Myanmar.

The Indo-Burma hill range is a part of the Arakan Yoma Suture zone that stretches south through Andaman – Nicobar island chain to Sunda. The elevation of the Eastern Hills (Purvanchal) decreases from north to south and it is characterized by rough terrain, dense forests and swift streams. All these Ranges are generally 2,000m or less in height but are rather forbidding because of dense forests, very rough terrace and inhospitable tribe.

It comprises of the following hills –
a.    Mishmi hills – Contains the loftiest range of the Purvanchal. Dapha Bum is its highest peak.
b.    Patkai Bum Range – It is the northernmost range forming the easternmost limit of the Great Himalaya Mountains, has synclinal structure and is made up of Tipam sandstone.
c.    Naga Hills – It lies south to the Patkai Bum and Saramati (3826m) is its highest peak. Patkai Bum and Naga hills form the watershed between India and Myanmar.
d.    Manipur Hills – It is south to Naga hills and form boundary between Manipur and Myanmar. Its central part is a large basin which appears to be bed of an old lake, a remnant of which occupies the south-east corner of the basin and is known as Loktak Lake. The Barail Range separates Naga Hills from Manipur hills.
e.    Mizo Hills (Lushai Hills) – It lies south to the Manipur hills and its highest point is the Blue Mountain (2157m) in the south.


SIGNIFICANCE OF HIMALAYA FOR INDIA:
•    Strategic significance:  Acts as a natural frontier of India with other countries (China, Afghanistan and Pakistan).

•    Climatic significance:  Prevent further northward movement of summer monsoon and also prevent cold northern winds from Siberia to enter into India.

•    Physical significance: The glaciers of the Himalayas feed the perennial rivers of North India. The rivers erode the mountain ranges and deposit the alluvial soils which are highly productive.

•    Agricultural Significance:  Rivers from Himalayas deposits a lot of sediment on its foothold, from which are formed India’s most fertile agricultural grounds known as Northern plains. The water of the mightly rivers arising out of the Himalayas is utilized for irrigation, industrial and domestic purpose. Alpine pastures provide nutritious grasses to the flock of transhumans. Tea, nuts, saffron, Apples and orchard plantation on the undulating slopes.

•    Economic significance: Huge hydro-electric power potential of Himalayan rivers, Himalayan timber, Himalayan Herbs & Medicinal plants. River sediments are used for a great source of minerals and building material.

•    Tourism Significance: Comprises of Large ecological biodiversity, natural views & hill stations. Abode of numerous tribes. The Himalayas are rich in flora and fauna. Natural beauty, hill resorts, and tourism. Great religious and mythological importance.

Northern Plains, Plateaus and Desert

NORTHERN PLAINS

•    They are formed by alluvial deposits brought by rivers – Indus, Ganga, Brahmaputra.
•    The Northern Plains extend 3200 km from east to west in Indian Physiography.
•    The Maximum depth of alluvium deposits varies from 1000-2000 m., it is 2400 km long & varying in width from 240 to approx. 320 km.
•    One of the largest, continuous and extensive plains
•    Fertile plain- flat topography -historically settled –dense population
•    30% of the world’s population on 10% of world’s agro-land.

a)     Northern plains subdivision
–    Bhabhar : (narrow belt parallel to Shiwalik foothills at slope break-up),
•    Lies along foothills of Shiwaliks, From Indus to Tista
•    Laid down by streams coming from hills
•    Comprises of pebble studded rocks (Highly porous bed plain)
•    Due to high porosity and permiablity- streams, rivers disappears here
•    Alluvial fans of Himalayan rivers – coarse depo – large boulders
•    Not good for cultivation

b)    Tarai : (narrow belt parallel to Shiwalik foothills at slope break-up),
•    Lies south of Bhabhar & runs parallel to it
•    Marked by re-emergence of underground streams of Bhabhar belt
•    Highly alluvial & agricultural land
•    Has a high water table due to groundwater percolating down from the adjacent zone
•    Bad drainage
•    Rivers re-appears –swamps, marshy
•    Naturally Sal forest
•    Terai of Bengal and Bihar is more developed
•    The region is excessively moist and thickly forested. It also receives heavy rainfall throughout the year and is populated with a variety of wildlife.
•    The Terai tract lies south of the Bhabar belt. The tract is marshy and lots of mosquitoes thrive there. The Terai belt is wider in eastern side especially in the Brahmaputra valley.
•    The high rainfall, newer alluvium makes it excessive damp and lots of forests are found here. This implies that Terai belt is rich in biodiversity.
•    Over the period of time, the forests have been cleared in various states such as Uttarakhand, Uttar Pradesh, Haryana, Punjab, and Jammu Divisions for cultivation of crops.
•    Terai belt is known for the good cultivation of sugar-cane, rice, wheat, maize, oilseeds, pulses, and fodder.

c)    Khadar:
•    Flood plains with newer and fresh alluvium deposited by  flood and rivers almost every year
•    Marked with fertile soil
•    Zone of intensive agriculture
•    Non porous, clayey and loamy
•    Slope between Bangar and Khadar: Punjab- ‘Dhayas’, UP- ‘Khol’, Bengal – ‘Bhils’, Bihar –’Taal’.
•    The Khadar land consists of sand, silt, clay and mud.
•    After Independence, most of the Khadar land has been brought under cultivation and devoted to sugarcane, rice, wheat, maize, oilseeds, legumes, and fodder crops.

d)    Bhangar:
•    Alluvial terrace lying above the level of flood plains
•    Composed of the oldest alluvial soil
•    Coarse in nature, contain kankar (lime nodules), pebbles, gravels
•    Soil of this region is locally known as kankar viz. calcareous concretions
•    Old flood plains of rivers – Dry land
•    The older alluvium soil is dark in colour, rich in humus content and productive.
•    Bhangar is generally a well drained and the most productive land of the Great Plains of India.

e)    Delta Plain:
•    The deltaic plain is an extension of the Khadar land.
•    It covers about 1.9 lakh sq km of area in the lower reaches of the Ganga River.
•    It is an area of deposition as the river flows in this tract sluggishly.
•    The deltaic plain consists mainly of old mud, new mud and marsh.
•    In the delta region, the uplands are called ‘Char’ while marshy areas are known as ‘Bili.
•    The delta of Ganga being an active one, is extending towards the Bay of Bengal.

Alluvial plains (located to the south of Tarai, mature stage of fluvial erosional and depositional landforms like sand bars, meanders. It is divided into Khadar and Bhangar).

•    East-west division of plains:

–    Rajasthan Plains (Indus): West of Aravalli, North- Gangasagar region, Extension of Punjab plains of Indus, West of Aravalli-Rajasthan Bagar, Drained by river Luni, Luni merged into Rann of Kutchh. Rajasthan Bagar: fluvial grasslands –Rajasthan steppe, Very fertile –Rohi tracts, Western most Rajasthan- marusthali/ Thar desert– sand dunes ‘Dhrians’.

–    Punjab plains (Indus): Fluvial plains –Ravi, Beas and Sutlej (tributaries of Indus), Khadar plains: fertile but limitations, Aridity, Basin topography (bad drainage) – salination.]

–    Gangetic plains:
Divisions:

•    Upper Gangetic plains- From Yamuna to Ghaghara plains, Rohilkhand plain, Sandy deposits.
•    Middle Gangetic plains- Kosi plain-called Magadh / Awadh /Anga plain, Flood-prone, shifting of river course of Kosi.
•    Lower Gangetic plains- Ganga enters WB-Sundarban delta, Lowland-almost sea level, Sagar Island, Lothian Island, Bengal tigers are belongs from this area.

–    Assam plains (Brahmaputra): Brahmaputra largest river of India (volume), Origin Mansarovar lake- enters as Dihang in Arunachal Pradesh, River course narrow- numerous stream flows -flood prone. Streams from north –swift flowing – form alluvial fans, Manas- Subansiri, Streams from south plateu –smooth flowing- Dibang, Lohit, Dhansiri, Kapilli.

Natural hazard and disaster
•    The  Indo-Gangetic  Zone  of  earthquake  prone  belt  runs  parallel  to  the  Himalayan  Zone  on  its  southern  side.
•    The earthquakes along the foothills are of medium to high intensity.
•    However, the earthquakes of this zone are more  harmful  due  to  high  density  of  population  in  this  area.
•    In  the  Great  plains  some  districts  of  Rajasthan  and  Uttar  Pradesh  receiving  rainfall  less  than  75  to  80  cm  of rainfall  with variability over  40 per  cent are  prone to  draught.
•    However, the  severest draught  have occurred  in comparatively wet areas such as Bihar and west Bengal, where rainfall is normally enough to allow high density of  population  and  where  failure  of  rainfall  can  affect  millions  of  people.
•    Being a plain area and  drained by various big and small rivers often breaching their limiting banks during the season  of  high  discharge,  this  area  is  frequently  hit  by  floods.

Importance of Great Plains
•    The Indo-Gangetic belt is the world’s most extensive expanse of uninterrupted alluvium formed by the deposition of silt by the numerous rivers.
•    The plains are flat and mostly treeless, making it conducive for irrigation through canals. The area is also rich in ground water sources.
•    The plains are the world’s most intensely farmed areas. Fertile alluvial soils, flat surface, slow moving perennial rivers and favourable climate facilitate an intense agricultural activity.
•    The main crops grown are rice and wheat, which are grown in rotation. Others include maize, sugarcane and cotton. The extensive use of irrigation has made Punjab, Haryana and western part of Uttar Pradesh the granary of India (Prairies are called the granaries of the world).
•    The Indo-Gangetic plains rank among the world’s most densely populated areas.
•    The Great Plains of India are covered with one of the most productive soils of the world.
•    Its soils have the capacity to grow any crop of the tropical and temperate regions.
•    The sedimentary rocks of plains have petroleum and natural gas deposits.
•    The rivers here have very gentle gradients which make them navigable over long distances.
•    The plains are often termed as the ‘Granary of India’. Most of the rivers traversing the Northern Plains of India are perennial in nature.
•    A number of canals have been carved out of these rivers which make agriculture more remunerative and sustainable.
•    The water table is high and suitable for tube well irrigation. The gentle gradient makes it navigable over long distances.
•    Cultural tourism: Several sacred places and centres of pilgrimage are situated in these plains e.g. Haridwar, Amritsar, Varanasi, Allahabad, Bodh Gaya, etc.

THE PENISULAR PLATEAU
•    The peninsular plateau of India is roughly triangular in shape with base coinciding with the southern edge of the great Northern plains and its apex is formed by Kanyakumari in south.
•    The northern boundary of the peninsular block is an irregular line running from Kutch along the western flank of Aravalis to near Delhi, and then roughly parallel to the Yamuna and Ganga as far as Rajmahal hills and then Ganga delta.
•    The Western Ghats and the Eastern Ghats form its western and eastern boundaries respectively in South. The entire plateau measures about 1600 km. in north-south and 1400 km. in east west direction.
•    It covers about half of the total area of the country. It is the largest physiographic unit of India.
•    The average height of the plateau is about 600 to 900 m above MSL.
•    Largest of India’s physical divisions – Comprises of broad & shallow valleys with rounded hills
•    This Triangular shape plateau; composed of the oldest rocks & Surrounded by hills.
•    Narmada – Tapi divides it into 2 parts viz. Central highland & Deccan plateau.
•    The general slope of the plateau is from west to east with the exception of Narmada-Tapi rift which slopes westwards.

DIVISION OF THE PENISUALR PLATEAU:
A.    The Central Highlands
•    Lies to the north of the Narmada river between Aravali in North & Vindhya range in south.


–    Covers the major portion of the Malwa plateau (Madhya Pradesh)
–    Rivers in this region flow from southwest to northeast; which indicates the slope of this region
–    Further extension of it is Bundelkhand, Bhaghelkhand & Chhota Nagpur Plateau
–    Chambal & Betwa flows through it ’! Region known as Bed land (Not fit for cultivation)

a)    Malwa Plateau: 
•    Lies in Madhya Pradesh b/w Aravali & Vindhyas
•    Extension of it is Bundelkhand, Bhaghelkhand & Chota Nagpur Plateau

b)    Bundelkhand Plateau:
•    Lies along the borders of UP & MP
•    Has been transformed into ravines by extensive erosional activities of river Chambal & its tributaries.

c)    Chhotanagpur Plateau:   
•    NE part of peninsular plateau
•    Includes Jharkhand, parts of Chhattisgarh & WB,
•    Highest Peak Parasnath
•    Famous as Patland plateau & known as ruhr of India.

B.    Deccan Plateau
•    Largest plateau in India; Lies to the south of the Narmada River; Shaped as inverted triangle.
•    Surrounded by Satpura hills, Mahadeo hills, Maikala range, Amarkantak hills and Rajmahal hills, the north; Western Ghats in the west and the Eastern Ghats in the east
•    Volcanic in origin, made up of horizontal layers of solidified lava forming trap structure with step like appearance
•    Sedimentary layers are also found in between the layers of solidified lava, making it inter-trapping in structure
•    Average elevation of Western Ghats is 900 – 1600 metres; compared to 600 metres of Eastern Ghats
•    Slopes towards east and south and descends abruptly towards west making sahayadri ranges
•    The plateau is suitable for the cultivation of cotton; home to rich mineral resources & a source to generate hydroelectric power.


Western Ghats
•    Folded parts of Deccan Plateau
•    Also known as Shayadries
•    More Continuous & higher than Eastern Ghats
•    Separated from coast by narrow coastal plains
•    Rich watersheds give birth to large peninsular rivers like Godavari and Krishna
•    Extends from Tapi in North to Kanyakumari in south.

Maharashtra Plateau:
•    Deccan trap topography, almost entirely covered by lack cotton soil called regur.
•    Broad and shallow valleys of river: Godavari, Krishna, Bhima, Wainganga- Painganga-wardha system.
•    Bounded by sahyandris on west, Satpuda on north comprises Ajanta range, Balghat range, Harishchandra range, Satmala hills (Chikhaldara-on Gawaligarh hills).


Eastern Ghats
•    Extends from Odisha to North of Nilgiri hills
•    Discontinuous & lower then Western Ghats
•    Do not give birth to important rivers like western ghats
•    Separated from coast by very wide coastal plains
•    Geologically older than western ghats
•    Mahanadi, Godavari, Krishna, Kaveri cut through this range to merge with Bay of Bengal
•    The Western Ghats and the Eastern Ghats meet in the Nilgiri hills

Telangana Plateau
•    Part of deccan plateau
•    Located on north of river Krishna

Karnataka Plateau
•    South of deccan lava region
•    Consist of Bababudan hills
•    Famous for iron ores

Dandakaranya Plateau
•    Forms parts of Chhatisgarh & Odisha
•    Contains igneous & metamorphic rocks of Archaen period
•    River Indravati & Mahandi flows through this plateau
•    Largely inhabited by Gond tribes

Shillong Plateau/Meghalaya plauteau:
•    Separated from the peninsular plateau block by a wide gap called Garo-Rajmahal Gap formed due to down faulting which was later filled up by Ganga deposits.
•    Western-central and eastern parts are known as the Garo(900m.), Khasi-Jaintia( 1500m), Mikir (700m) hills.
•    Shillong is the highest point of the plateau at 1961m on khasi hills tableland.
•    Part of Peninsular Deccan Plateau
•    World’s highest rainfall receiving point Mawsynram is situated here.

Importance of the Peninsular Plateau Region
•    Ancient and stable landmass
•    Mineral storehouse of India, -Iron, Manganese, Copper, Bauxite, Mica, Gold, etc.
•    98% of Gondwana coal deposits come from PP region.
•    Rocks: Slate, Shale, Granite, Marble.
•    Black cotton soil.
•    Western Ghats: cause of SW monsoon rainfall.
•    Tourism: Hills Stations- Ooty, Mahabaleshwar, Pachmarhi, Matheran, Khandala.
•    Forest and forest products.


THE GREAT INDIAN DESERT


•    Extends from the western margins of the Aravali Hills
•    Sometimes considered a part of the peninsular plateaus.
•    Oldest Fold Mountains of the world-long period of erosion, therefore also called relict mountains. Stretch 800 km. elevation; 300-900 m, highest peak: Guru shikhar, (near mt. Abu 1722 km.)
•    Some part fairly rich in minerals. One branch of the Aravali extend to the Lakshadweep through Gulf of Khambat.

•    Important rivers originating through desert:
–    Sabarmati and Lluni- Luni is the only prominent river ( flow in west direction)
–    Ahmedabad situated on the banks of Sabarmati and Vadodara on Mahi sagar river.

•    Dry N-W part- Thar Desert, Great Indian Desert.
–    It extends to Pakistan and dominated by shifting sand dunes, area of inland drainage.

•    Important lakes:
Deewdana, Sambar(important for salt production)

•    Minerals- Gypsum, Marble, Zinc, Lead, Copper, Mica

Coastal Plains and Islands

•    India has a coastline of 7516.6 Km [6100 km of mainland coastline, coastline of 1197 Indian islands] touching 13 States and Union Territories (UTs).
•    The straight and regular coastline of India is the result of faulting of the Gondwanaland during the Cretaceous period. (Continental Drift)
•    As such the coast of India does not offer many sites for good natural harbours.
•    The Bay of Bengal and the Arabian Sea came into being during the Cretaceous or early Tertiary period after the disintegration of Gondwanaland
•    Extends from Kutch in Gujarat in the west to the Gangetic delta in the east
•    The coast of India is divided into western coast and eastern coastal plains.
•    The coastal regions of India are known for agriculture, trade, industrial centres, tourist centres, fishing and salt making.
•    They also provide important hinterlands for the ports.

EMERGENCE AND SUBMERGENCE COASTS
•    Coastline of emergence is formed either by an uplift of the land or by the lowering of the sea level. Coastline of submergence is an exact opposite case.
•    Bars, spits, lagoons, salt marshes, beaches, sea cliffs and arches are the typical features of emergence. {Marine Landforms}
•    The east coast of India, especially its south-eastern part (Tamil Nadu coast), appears to be a coast of emergence.
•    The west coast of India, on the other hand, is both emergent and submergent.
•    The northern portion of the coast is submerged as a result of faulting and the southern portion, that is the Kerala coast, is an example of an emergent coast.
•    Coramandal coast (Tamil Nadu) – Coastline of emergence
•    Malabar coast (Kerala Coast) – Coastline of emergence
•    Konkan coast (Maharashtra and Goa Coast) – Coastline of submergence.

WESTERN COASTAL PLAINS
•    The west coast strip extends from the Gulf of Cambay (Gulf of Khambhat) in the north to Cape Comorin (Kanniyakumari). Lies between Western Ghats & Arabian sea from Gujrat in north to Kanyakumari in south.
•    It is narrower & wetter than Eastern plains
•    Divided into Malabar coast, Kannada Coast, Konkan coast, Kanyakumari Coast, Kachchh and Kathiawad peninsula
•    It is made up of alluvium brought down by the short streams originating from the Western Ghats.
•    It is dotted with a large number of coves (a very small bay), creeks (a narrow, sheltered waterway such as an inlet in a shoreline or channel in a marsh) and a few estuaries. {Marine Landforms}
•    The estuaries, of the Narmada and the Tapi are the major ones.
•    The Kerala coast (Malabar Coast) has some lakes, lagoons and backwaters, the largest being the Vembanad Lake
•    Important Ports: Mumbai, Marmagoa, Cochin, Mangalore, Nhava-Sheva and Kandla.
•    Marked with Lagoons:  Ashtamudi & Vembanad called Kayals (Kerala).


a)    Kutch and Kathiawar region
•    Kutch and Kathiawar, though an extension of Peninsular plateau (because Kathiawar is made of the Deccan Lava and there are tertiary rocks in the Kutch area), they are still treated as integral part of the Western Coastal Plains as they are now levelled down.
•    The Kutch Peninsula was an island surrounded by seas and lagoons. These seas and lagoons were later filled by sediment brought by the Indus River which used to flow through this area. Lack of rains in recent times has turned it into arid and semi-arid landscape.
•    Salt-soaked plain to the north of Kutch is the Great Rann. Its southern continuation, known as the Little Rann lies on the coast and south-east of Kachchh.
•    The Kathiawar Peninsula lies to the south of the Kachchh. The central part is a highland of Mandav Hills from which small streams radiate in all directions (Radial Drainage). Mt. Girnar (1,117 m) is the highest point and is of volcanic origin.
•    The Gir Range is located in the southern part of the Kathiawar peninsula. It is covered with dense forests and is famous as home of the Gir lion.

b)    Gujarat Plain
•    The plain area between the Western Ghats and the Arabian Sea from the gulf of Kuchchh and Gulf of Khambat located on either side of Kathiawar Peninsula is called Gujarat Plains.
•    The Gujarat Plain lies east of Kachchh and Kathiawar and slopes towards the west and south west.
•    Formed by the rivers Narmada, Tapi, Mahi and Sabarmati, the plain includes the southern part of Gujarat and the coastal areas of the Gulf of Khambhat.
•    The eastern part of this plain is fertile enough to support agriculture, but the greater part near the coast is covered by windblown loess (heaps of sand).

c)    Konkan Plain
•    The Konkan Plain south of the Gujarat plain extends from Daman to Goa (50 to 80 km wide).
•    It has some features of marine erosion including cliffs, shoals, reefs and islands in the Arabian Sea.
•    The Thane creek around Mumbai is an important embayment (a recess in a coastline forming a bay) which provides an excellent natural harbour.

d)    Karnataka Coastal Plain
1.    Goa to Mangalore.
•    It is a narrow plain with an average width of 30-50 km, the maximum being 70 km near Mangalore.
•    At some places the streams originating in the Western Ghats descend along steep slopes and make waterfalls.
•    The Sharavati while descending over such a steep slope makes an impressive waterfall known as Gersoppa (Jog) Falls which is 271 m high.
•    Marine topography is quite marked on the coast.

2.    Kerala Plain
a)    The Kerala Plain also known as the Malabar Plain. Between Mangalore and Kanniyakumari.
b)    This is much wider than the Karnataka plain. It is a low lying plain.
c)    The existence of lakes, lagoons, backwaters, spits, etc. is a significant characteristic of the Kerala coast.
d)    The backwaters, locally known as kayals are the shallow lagoons or inlets of the sea, lying parallel to the coastline.
e)    The largest among these is the Vembanad Lake which is about 75 km long and 5-10 km wide and gives rise to a 55 km long spit that is called the Marine Landforms.

EASTERN COASTAL PLAINS
•    Lies between Eastern Ghats & Bay of Bengal from Gangetic delta in north to Kanyakumari in south
•    Broader but drier than Western plains
•    It is an emergent coastal plain, hence has less number of ports and harbours.
•    The Eastern Coast has well-developed deltas in Mahanadi, Godavari, Krishna, and Kaveri. The continental shelf extends upto 500 km into Sea.


•    Consists of following sub coasts

a)    Utkal coast –  Deltaic plains of Ganga to Mahanadi delta (Famous Chilka lake is located in this plain)
b)    Andhra Coast   –  Utkal plains to Pulicat lake (Contains deltas of Godavari & Krishna Rivers, & famous Kolleru lake)
c)    Northern Circars – Utkal Coast and Andhra Coast (Between Mahanadi & Krishna).
d)    Coromandal Coast – Between Krishna & Kanyakumari (Consist of Kaveri Delta)Freshwater Kolleru Lake – Between Godavari & Krishna,
•    Marked with Famous Lagoons – Chilka lake (Orissa) & Pulicat (Tamilnadu)
•    Chilka Lake is the largest salt water lake in India
•    It lies in the state of Odisha, to the south of the Mahanadi Delta.
•    Coromandal coastal plain is  Spread from Northern chennai (Pulicat lake) to Kanyakumari in the south.
•    Contains deltaic plains of Kaveri & called as Pride of south India.

THE INDIAN ISLANDS
Apart  from  the  large  numbers of  islands in  the  near  proximity  of  the  Indian  coast,  there are  two  main groups.

•    Total 247 islands in India :  204 islands in Bay of Bengal and 43 in the Arabian Sea
•    Few coral islands also in the Gulf of Mannar.
•    Andaman and Nicobar Islands in Bay of Bengal consist of hard volcanic rocks.
•    The middle Andaman and Nicobar Islands are the largest islands of India.
•    Lakshadweep islands in the Arabian Sea are formed by corals.
•    The southern – most point of India is in Nicobar Island, known as Indira Point.
•    Formerly ‘Indira point’ was called Pigmalion Point, it is submerged now, after 2004 Tsunami
•    Some of  islands  in  the  Indian  ocean  away  from  the  coast.  They  are  as  follows:

ANDAMAN AND NICOBAR ISLAND
•    The  group  of  islands  form  an  accurate  chain,  convex  to  the  west,  for  a  distance  of  about  590  km,  with maximum width of about 58 km.
•    This archipelago is composed of 265 big and small islands.
•    The entire chain consists of two distinct groups of islands.  The  great  Andaman  group  of  islands  in  the  north  is  separated  by the  Ten  degree  channel  from  Nicobar  group  in  the  south.
•    The Andaman group of islands consists of 203 islands.
•    Volcanic islands representing submarine volcanism
•    Represent the surfaces of submerged folds viz. extension of Himalaya, precisely Arakan yoma Fold Mountains of Myanmar.
•    Formed of Granite rocks & have high hills &l peaks for ex. Saddle peak
•    Equatorial climate with tropical rain-forests
•    The Nicobar group of islands consists of 7 big and 12 small islands together with several tiny islands.
•    Most of these islands are made of tertiary sandstone, limestone and shall rest on basic and ultra-basic volcanoes.
•    The  Barren  and  Narcondam  islands,  north  of  port  Blair,  are  volcanic  islands.
•    Some of the islands are fringed with coral reefs.
•    Saddle (737m) peak in north Andaman is the highest peak.


THE LAKSHADWEEP ISLAND


•    It is in the Arabian Sea having a group of 25 small islands. The total land area is 32km
•    Volcanic islands representing submarine volcanism
•    Represent the surfaces of submerged folds viz. extension of Himalaya, precisely Arakan yoma Fold Mountains of Myanmar
•    Formed of Granite rocks & have high hills &l peaks for ex. Saddle peak
•    Equatorial climate with tropical rain-forests
•    The islands north to  11°N  latitude  are  known  as  Amendivi  Islands  while  those  south  of  this  latitude  are  called  Cannanore islands.
•    In the extreme south is the Minicoy Island.
•    All are tiny islands of coral origin and are surrounded by fringing reefs. The largest and most advanced is Minicoy Island. These Island form of coral deposits, are called atolls, are circular or horse shoe shaped coral reefs.
•    Most of the island have low elevation and  do  not  rise  more  than  five  metres  above  sea  level.

PROMINENT INDIAN ISLAND:


SIGNIFICANCE OF INDIAN OCEAN FOR INDIA:
•    Strategic significance: India overlooks some of the most important sea lanes viz. Suez Canal, Malacca Strait
•    Economic significance: Long coastline, 2.02 million sq km EEZ (Exclusive economic zone)
•    Tourism Significance: Marine biodiversity and rich ecosystem with coral reefs, mangroves
•    Other: Large Fishing potential, Wave energy & Tidal energy potential, Zone of Hydrocarbons,
•    Generation of south west Monsoon.

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