A. The North and North- eastern Mountains

Details

• Consist of the Himalayas and the North- eastern hills.
• Himalayas- series of parallel mountain ranges
• Greater Himalayan range- Great Himalayas Trans+ Himalayan range
• Middle Himalayas and
• The Shiwalik.
• The general orientation of these ranges is from northwest to the southeast direction in the north- western part of India.
• Himalayas in the Darjiling and Sikkim regions lie in an east- west direction, while in Arunachal Pradesh they are from southwest to the northwest direction.
• In Nagaland, Manipur and Mizoram, they are in the north south direction.
• Himalayas- wall between the Indian subcontinent and the Central and East Asian countries.

Himalayas can be divided into the following sub-divisions:

1. Kashmir or North- western Himalayas
2. Himachal and Uttaranchal Himalayas
3. Darjiling and Sikkim Himalayas
4. Arunachal Himalayas
5. Eastern Hills and Mountains

Kashmir or North- western Himalayas

• Karakoram, Ladakh, Zaskar and Pir Panjal
• The north- eastern part of the Kashmir Himalayas is a cold desert, which lies between the Greater Himalayas and the Karakoram ranges.
• Between the Great Himalayas and the Pir Panjal range, lies the world famous valley of Kashmir and the famous Dal Lake.
• Important glaciers of South Asia such as the Baltoro and Siachen are also found in this region.
• The Kashmir Himalayas are also famous for Karewas formations, which are useful for the cultivation of Zafran, a local variety of saffron.
• Passes- Zoji La on the Great Himalayas, Banihal on the Pir Panjal, Photu La on the Zaskar and Khardung La on the Ladakh range.
• Fresh lakes- Dal and Wular
• Salt water lakes- Pangong Tso and Tso Moriri
• Drained by the river Indus, and its tributaries such as the Jhelum and the Chenab.
• Jhelum in the valley of Kashmir is still in its youth stage and yet forms meanders – a typical feature associated with the mature stage in the evolution of fluvial land form

The Himachal and Uttarakhand Himalayas

• Between the Ravi in the west and the Kali (a tributary of Ghaghara) in the east.
• Drained by- Indus and the Ganga.
• Tributaries of the Indus include the river Ravi, the Beas and the Satluj, and the tributaries of Ganga flowing through this region include the Yamuna and the Ghaghara.
• Himalayas is an extension of the Ladakh cold desert, which lies in the Spiti subdivision of district Lahul and Spiti.
• All the three ranges of Himalayas are prominent in this section also.
• These are the Great Himalayan range, the Lesser Himalayas (which is locally known as Dhauladhar in Himachal Pradesh and Nagtibhain Uttarakhand) and the Shiwalik range from the North to the South.
• The two distinguishing features- Shiwalik and Dun formations
• Some important duns located in this region are the Chandigarh-Kalka dun, Nalagarh dun, Dehra Dun, Harike dun and the Kota dun, etc.
• Dehra Dun is the largest of all the duns
• In the Great Himalayan range, the valleys are mostly inhabited by the Bhotia‘s.
• The famous Valley of flowers is also situated in this region.
• The places of pilgrimage such as the Gangotri, Yamunotri, Kedarnath, Badrinath and Hemkund Sahib are also situated in this part.
• The region is also known to have five famous Prayags

The Shiwalik

• The word Shiwalik has its origin in the geological formation found in and around a place called Sivawala near Dehra Dun which was once a headquarter of the Imperial Survey
• In Kashmir Valley, the meanders in Jhelum river are caused by the local base level provided by the erstwhile larger lake of which the present Dal Lake is a small part

The Darjeeling and Sikkim Himalayas

• Bordered by Nepal Himalayas in the west and Bhutan Himalayas in the east.
• Known for its fast-flowing rivers such as Tista,
• High Mountain peaks – Kanchenjunga (Kanchengiri), and deep valleys.
• The higher reaches of this region are inhabited by Lepcha tribes while the southern part, particularly the Darjiling
• Himalayas, has a mixed population of Nepalis, Bengalis and tribals from Central India.
• Duar formations- used for the development of tea gardens

The Arunachal Himalayas

• Extend from the east of the Bhutan Himalayas up to the Diphu pass in the east.
• The general direction of the mountain range is from southwest to northeast.
• Important Mountain peaks- Kangtu and Namcha Barwa.
• These ranges are dissected by fast-flowing rivers from the north to the south, forming deep gorges.
• Brahmaputra flows through a deep gorge after crossing Namcha Barwa.
• Important rivers- Kameng the Subansiri, the Dihang, the Dibang and the Lohit.
• These are perennial with the high rate of fall, thus, having the highest hydro-electric power potential in the country.
• Tribes from west to east- Monpa, Daffla, Abor, Mishmi, Nishi and the Nagas.
• Shifting or slash and burn cultivation (Jhumming)
• Most of the interactions are carried through the duar region along the Arunachal-Assam border

The Eastern Hills and Mountains

General alignment from the north to the south direction

Local names-

• North- Patkai Bum, Naga hills, the Manipur hills
• South- Mizo or Lushai hills
• Jhum cultivation
• Barak River – Manipur and Mizoram.
• Manipur- Loktak lake
• Mizoram which is also known as the Molassis basin‘which is made up of soft unconsolidated deposits.
• Most of the rivers in Nagaland form the tributary of the Brahmaputra.
• While two rivers of Mizoram and Manipur are the tributaries of the Barak river, which in turn is the tributary of Meghna;
• Rivers in the eastern part of Manipur are the tributaries of Chindwin, which in turn is a tributary of the Irrawaddy of Myanmar

B. The Northern Plains

Details

• Formed by the alluvial deposits brought by the rivers – the Indus, the Ganga and the Brahmaputra
• 3,200 km; east to the west
• Average width- 150-300 km
• Maximum depth – 1,000-2,000 m

From the north to the south, these can be divided into three major zones: the Bhabar, the Tarai and the alluvial plains.

• The alluvial plains can be further divided into the Khadar and the Bhangar.
• Bhabar is a narrow belt ranging between 8-10 km parallel to the Shiwalik foothills at the break-up of the slope.
• South of the Bhabar is the Tarai belt, with an approximate width of 10-20 km where most of the streams and rivers re-emerge without having any properly demarcated channel, thereby, creating marshy and swampy conditions known as the Tarai.
• This has a luxurious growth of natural vegetation and houses a varied wild life.
• The south of Tarai is a belt consisting of old and new alluvial deposits known as the Bhangar and Khadar respectively.
• These plains have characteristic features of mature stage of fluvial erosional and depositional landforms such as sand bars, meanders, ox- bow lakes and braided channels.
• The Brahmaputra plains are known for their riverine islands and sand bars.
• Periodic floods and shifting river courses forming braided streams.
• The mouths of these mighty rivers also form some of the largest deltas of the world, for example, the famous Sunderbans delta.
• fertile alluvial soil cover which supports a variety of crops like wheat, rice, sugarcane and jute

C. The Peninsular Plateau

Details

• Rising from the height of 150 m above the river plains up to an elevation of 600-900m is the irregular triangle
• Delhi ridge in the northwest, (extension of Aravalis), the Rajmahal hills in the east, Gir range in the west and the Cardamom hills in the south constitute the outer extent of the Peninsular plateau.
• However, an extension of this is also seen in the northeast, in the form of Shillong and Karbi-Anglong plateau.
• The Peninsular India is made up of a series of patland plateaus such as the Hazaribagh plateau, the Palamu plateau, the Ranchi plateau, the Malwa plateau, the Coimbatore plateau and the Karnataka plateau, etc.
• The general elevation of the plateau is from the west to the east, which is also proved by the pattern of the flow of rivers.
• Physiographic features- tors, block mountains, rift valleys, spurs, bare rocky structures, series of hummocky hills and wall-like quartzite dykes offering natural sites for water storage.
• The western and north- western part of the plateau has an emphatic presence of black soil.
• This Peninsular plateau has undergone recurrent phases of upliftment and submergence accompanied by crustal faulting and fractures.
• These spatial variations have brought in elements of diversity in the relief of the Peninsular plateau.
• The north-western part of the plateau has a complex relief of ravines and gorges.
• Ravines- Chambal, Bhind and Morena

On the basis of the prominent relief features, the Peninsular plateau can be divided  into three broad groups-

1. The Deccan Plateau
2. The Central Highlands
3. The North- eastern Plateau

The Deccan Plateau

• Bordered by the Western Ghats in the west, Eastern Ghats in the east and the Satpura, Maikal range and Mahadeo hills in the north.
• Western Ghats are locally known by different names such as Sahyadri in Maharashtra, Nilgiri hills in Karnataka and Tamil Nadu and Anaimalai hills and Cardamom hills in Kerala.
• Western Ghats are comparatively higher in elevation and more continuous than the Eastern Ghats.
• Anamudi‘ (2,695 m), the highest peak of Peninsular plateau is located on the Anaimalai hills of the Western Ghats followed by Dodabetta (2,637 m) on the Nilgiri hills.
• Eastern Ghats comprising the discontinuous and low hills are highly eroded by the rivers such as the Mahanadi, the Godavari, the Krishna, the Kaveri, etc.
• Important ranges- Javadi hills, the Palconda range, the Nallamala hills, the Mahendragiri hills, etc.
• The Eastern and the Western Ghats meet each other at the Nilgiri hills.

The Central Highlands

• They are bounded to the west by the Aravali range.
• The Satpura range is formed by a series of scarped plateaus on the south, generally at an elevation varying between 600-900 m above the mean sea level.
• This forms the northernmost boundary of the Deccan plateau. It is a classic example of the relict mountains which are highly denuded and form discontinuous ranges.
• The extension of the peninsular plateau can be seen as far as Jaisalmer in the West, where it has been covered by the longitudinal sand ridges and crescent-shaped sand dunes called barchans.
• This region has undergone metamorphic processes in its geological history, which can be corroborated by the presence of metamorphic rocks such as marble, slate, gneiss, etc.

The North- eastern Plateau

• In fact it is an extension of the main peninsular plateau.
• It is believed that due to the force exerted by the north- eastward movement of the Indian plate at the time of the Himalayan origin, a huge fault was created between the Rajmahal hills and the Meghalaya plateau.
• Later, this depression got filled up by the deposition activity of the numerous rivers.
• Today, the Meghalaya and Karbi Anglong plateau stand detached from the main Peninsular Block.

The Meghalaya plateau is further sub-divided into three-

1. The Garo Hills;
2. The Khasi Hills;
3. The Jaintia Hills

• An extension of this is also seen in the Karbi Anglong hills of Assam. Similar to the Chotanagpur plateau, the Meghalaya plateau is also rich in mineral resources like coal, iron ore, sillimanite, limestone and uranium.
• This area receives maximum rainfall from the south west monsoon.
• As a result, the Meghalaya plateau has a highly eroded surface.
• Cherrapunji displays a bare rocky surface devoid of any permanent vegetation cover.

D. The Indian Desert

Details

• To the northwest of the Aravali hills lies the Great Indian Desert.
• Undulating topography dotted with longitudinal dunes and barchans.
• Low rainfall below 150 mm per year; hence, it has arid climate with low vegetation cover.
• Also known as Marusthali
• The Luni river in the southern part
• Low precipitation and high evaporation
• There are some streams which disappear after flowing for some distance and present a typical case of inland drainage by joining a lake or playa.
• The lakes and the playas have brackish water which is the main source of obtaining salt.

E. The Coastal Plains

(i) The western coastal plains; (ii) the eastern coastal plains

The Western coastal plains

• Example of submerged coastal plain
• It is believed that the city of Dwaraka which was once a part of the Indian mainland situated along the west coast is submerged under water.
• Because of this submergence it is a narrow belt and provides natural conditions for the development of ports and harbours.
• Examples- Kandla, Mazagaon, JLN port Navha Sheva, Marmagao, Mangalore, Cochin, etc.

Western coast may be divided into following divisions –

• The Kachchh and Kathiawar coast in Gujarat,
• Konkan coast in Maharashtra,
• Goan coast and Malabar coast in Karnataka and Kerala respectively
• The rivers flowing through this coastal plain do not form any delta.
• The Malabar coast has got certain distinguishing features in the form of Kayals‘ (backwaters), which are used for fishing, inland navigation and also due to its special attraction for tourists.
• Every year the famous Nehru Trophy Vallamkali (boat race) is held in Punnamada Kayal in Kerala.

The Eastern coastal plain

• Emergent coast
• There are well- developed deltas here, formed by the rivers flowing eastward in to the Bay of Bengal.
• These include the deltas of the Mahanadi, the Godavari, the Krishna and the Kaveri.
• Because of its emergent nature, it has less number of ports and harbours.
• The continental shelf extends up to 500 km into the sea, which makes it difficult for the development of good ports and harbours

F. The Islands

There are two major island groups in India – one in the Bay of Bengal and the other in the Arabian Sea.

The Bay of Bengal

• Approx 572 islands/islets
• Between 6°N-14°N and 92°E -94°E.
• The two principal groups of islets include the Ritchie‘s archipelago and the Labrynth island. The entire group of island is divided into two broad categories – the Andaman in the north and the Nicobar in the south.
• They are separated by a water body which is called 10º degree channelhese islands are an elevated portion of submarine mountains.
• However, some smaller islands are volcanic in origin.
• Barren island, the only active volcano in India is also situated in the Nicobar islands.
• The coastal line has some coral deposits, and beautiful beaches.
• These islands receive convectional rainfall and have an equatorial type of vegetation.

The Islands of the Arabian sea-

• Lakshadweep and Minicoy
• between 8°N-12°N and 71°E -74°E longitude.
• These islands are located at a distance of280 km-480 km off the Kerala coast is built of coral deposits.
• There are approximately 36 islands of which 11 are inhabited.
• Minicoy is the largest island with an area of 453 sq. km.
• The entire group of islands is broadly divided by the Eleventh degree channel, north of which is the Amini Island and to the south of the Cannanore Island.
• The Islands of this archipelago have storm beaches consisting of unconsolidated pebbles, shingles, cobbles and boulders on the eastern sea boar