Monday 16 September 2019



Himalayan Ranges: Shiwaliks, Middle Himalayas, Greater Himalayas, Trans-Himalayas & Purvanchal


Major Physical Divisions of India

  1. The Himalayas (young fold mountains),
  2. Indo-Gangetic Plain (monotonous topography – featureless topography),
  3. The Peninsular Plateau (one of the most stable landmasses; one of the oldest plateaus of the world),
  4. Coastal Plains (Sediments due to fluvial action).
  5. The Indian Islands [Coral Islands == coral reef built up on atolls – Lakshadweep. Tectonic == Andaman and Nicobar Islands – Interaction between Indian Plate and Eurasian plate] and

Peninsular Plateau

  • Includes the entire south India, central India, Aravalis, Rajmahal hills, Meghalaya plateau, Kuchchh-Kathiawar region (Gujarat) etc..
  • It is the oldest and the most stable landmass of India.

Himalayas

  • Includes the Himalayas, Purvanchal and their extensions Arakan Yoma (Myanmar) and Andaman and Nicobar Islands (but we will consider these as islands only).
  • It is the youngest and highly unstable landmass of India. [Continent – Continent Convergence]
  • Tectonic movements are very common.

Indo-Gangetic Plain

  • Between Peninsular and Himalayan region.
  • Most youthful, monotonous [lack of change or variety] region prone to tectonic forces.

Coastal Plains

  • Eastern Coastal Plains and Western Coastal Plains.
  • Formed due to consolidation of sediments brought by rivers (fluvial deposits).
  • Highly stable just like peninsular plateau.

Indian Islands

  • Two major groups – Lakshadweep and, Andaman and Nicobar islands.
  • Lakshadweep [Hotspot] are group of atolls occupied by coral reefs. No significant volcanism or tectonic activity in recent past. Highly vulnerable to sea-level rise.
  • Andaman and Nicobar islands – Continuation of Arakan Yoma. Has active volcanoes and is tectonically active.

Type of Topography

Extent in %

Mountainous (more than 2135 m above sea level)10.7
Hilly area (305 – 2135 m above sea level)18.6
Plateau (305 – 915 m above sea level)27.7
Plains43

Division of the Himalayas

Formation of Himalayas explained in Continent – Continent Convergence.
  1. Shiwaliks or outer Himalayas
  2. Lesser or Middle Himalayas
  3. The Greater Himalayas
  4. The Trans-Himalayas – Tibetan Himalayas.
  5. The Eastern Hills – Purvanchal: A chain of hills in North-East India.

Himalayan Ranges

  • Series of several parallel or converging ranges.
  • The ranges are separated by deep valleys creating a highly dissected topography [(of a plateau or upland) divided by a number of deep valleys].
  • The southern slopes have steep gradients and northern slopes have comparatively gentler slopes. [Scaling Mount Everest is less hectic from the northern side. But China puts restrictions so climbers take the steeper southern slopes from Nepal]
  • Most of the Himalayan ranges fall in India, Nepal and Bhutan. The northern slopes are partly situated in Tibet (trans-Himalayas) while the western extremity lies in Pakistan, Afghanistan and Central Asia.
  • Himalayas between Tibet and Ganga Plain is a succession of three parallel ranges.

Shiwalik Range

  • Also known as Outer Himalayas.
  • Located in between the Great Plains and Lesser Himalayas.
  • The altitude varies from 600 to 1500 metres.
  • Runs for a distance of 2,400 km from the Potwar Plateau to the Brahmaputra valley.
  • The southern slopes are steep while the northern slopes are gentle.
  • The width of the Shiwaliks varies from 50 km in Himachal Pradesh to less than 15 km in Arunachal Pradesh.
  • They are almost unbroken chain of low hills except for a gap of 80-90 km which is occupied by the valley of the Tista River and Raidak River.
  • Shiwalik range from North-East India up to Nepal are covered with thick forests but the forest cover decreases towards west from Nepal (The quantum of rainfall decreases from east to west in Shiwaliks and Ganga Plains).
  • The southern slopes of Shiwalik range in Punjab and Himachal Pradesh are almost devoid of forest cover. These slopes are highly dissected by seasonal streams called Chos.
  • Valleys are part of synclines and hills are part of anticlines or antisynclines.
anticline-syncline

Formation (Formation of Himalayas already explained)

  • Shiwaliks were formed last of all the ranges (2-20 million years ago).
  • The Shiwaliks are consolidated sands, gravels and conglomerate deposits [Alluvial fans] which were brought by the rivers flowing from the higher ranges.
  • These deposits were folded and hardened due to compression offered by the northward movement of Indian plate.

The Shiwaliks are known by different names in different areas

Region

Name of Shiwaliks

Jammu RegionJammu Hills
Dafla, Miri, Abor and Mishmi HillsArunachal Pradesh
The Dhang Range, Dundwa RangeUttarakhand
Churia Ghat HillsNepal

Explain the formation of Duns (Duras)

  • Shiwalik Hills were formed by the accumulation of conglomerates (sand, stone, silt, gravel, debris etc.).
  • These conglomerates, in the initial stages of deposition, obstructed the courses of the rivers draining from the higher reaches of the Himalayas and formed temporary lakes.
  • With passage of time, these temporary lakes accumulated more and more conglomerates. The conglomerates were well settled at the bottom of the lakes.
  • When the rivers were able to cut their courses through the lakes filled with conglomerate deposits, the lakes were drained away leaving behind plains called ‘duns’ or ‘doons’ in the west and ‘duars’ in the east.
  • Dehra Dun in Uttarakhand is the best example [75 km long and 15-20 km wide]
  • Kotah, Patli Kothri, Chumbi, Kyarda, Chaukhamba, Udhampur and Kotli are other important duns.

Middle or the Lesser Himalaya

  • In between the Shiwaliks in the south and the Greater Himalayas in the north.
  • Runs almost parallel to both the ranges.
  • It is also called the Himachal or Lower Himalaya.
  • Lower Himalayan ranges are 60-80 km wide and about 2400 km in length.
  • Elevations vary from 3,500 to 4,500 m above sea level.
  • Many peaks are more than 5,050 m above sea level and are snow covered throughout the year.
  • Lower Himalayas have steep, bare southern slopes [steep slopes prevents soil formation] and more gentle, forest covered northern slopes.
  • In Uttarakhand, the Middle Himalayas are marked by the Mussoorie and the Nag Tibba ranges.
  • The Mahabharat Lekh, in southern Nepal is a continuation of the Mussoorie Range
  • East of the Kosi River, the Sapt Kosi, Sikkim, Bhutan, Miri, Abor and Mishmi hills represent the lower Himalayas.
  • The Middle Himalayan ranges are more friendly to human contact.
Majority of the Himalayan hill resorts like Shimla, Mussoorie, Ranikhet, Nainital, Almora and Darjeeling, etc. are located here.

Important ranges of Lesser Himalayas

Region

The Pir Panjal RangeJammu and Kashmir (They are to the south of Kashmir Valley)
The Dhaola Dhar RangeHimachal Pradesh
The Mussoorie Range and The Nag Tiba RangeUttarakhand
Mahabharat LekhNepal

The Pir Panjal range

  • The Pir Panjal range in Kashmir is the longest and the most important range.
  • It extends from the Jhelum river to the upper Beas river for over 300 km.
  • It rises to 5,000 metres and contains mostly volcanic rocks.

Passes in Pir Panjal

  • Pir Panjal Pass (3,480 m), the Bidil (4,270 m), Golabghar Pass (3,812 m) and Banihal Pass (2,835 m).
  • The Banihal Pass is used by the Jammu-Srinagar highway and Jammu-Baramula railway.
  • The Kishanganga, the Jhelum and the Chenab cut through the range.
  • Southeast of the Ravi, the Pir Panjal continues as Dhaola Dhar range, passing through Dalhousie, Dharmshala, and Shimla.

Important Valleys

  • Between the Pir Panjal and the Zaskar Range of the main Himalayas, lies the valley of Kashmir. (average elevation is 1,585 m above mean sea level)
  • The synclinal basin of the valley is floored with alluvial, lacustrine [lake deposits], fluvial [river action] and glacial deposits. {Fluvial Landforms, Glacial Landforms}
  • Jehlum River meanders through these deposits and cuts a deep gorge in Pir Panjal through which it drains. (Kashmir is like a basin with very few outlets)
  • In Himachal Pradesh there is Kangra Valley. It is a strike valley and extends from the foot of the Dhaola Dhar Range to the south of Beas.
  • On the other hand, the Kulu Valley in the upper course of the Ravi is transverse valley.

Strike valley vs. Transverse valley

  • A valley perpendicular to the slope or parallel to the ridge [also called as longitudinal valley]
  • In contrast, transverse streams cut valleys parallel to the slope (along the dip).
Strike valley -Transverse valley

The Great Himalaya

  • Also known as Inner Himalaya, Central Himalaya or Himadri.
  • Average elevation of 6,100 m above sea level and an average width of about 25 km.
  • It is mainly formed of the central crystallines (granites and gneisses) overlain by metamorphosed sediments [limestone]. {Rock System}
  • The folds in this range are asymmetrical with steep south slope and gentle north slope giving ‘hog back (a long, steep hill or mountain ridge)’ topography.
  • This mountain arc convexes to the south just like the other two.
  • Terminates abruptly at the syntaxial bends. One in the Nanga Parbat in north-west and the other in the Namcha Barwa in the north-east.
  • This mountain range boasts of the tallest peaks of the world, most of which remain under perpetual snow.
highest mountains of the world - eight thousanders

Regional name of Mount Everest

Region

Sagarmatha (The Goddess of the Sky)Nepal
Chomlungma (Mother of the World)China (Tibet)
  • Mount Everest was first located by George Everest, the then Surveyor General of India in 1841 and in 1852 it was established as the highest peak of the world by the Great Trigonometrical Survey of India.

Passes in the Greater Himalayas

  • The passes because they are generally higher than 4,570 m above sea level and are snowbound for most of the year.

State

Passes of Greater Himalayas

Jammu and Kashmir
  1. Burzil Pass
  2. Zoji La [La means pass]
Himachal Pradesh
  1. Bara Lacha La
  2. Shipki La [The Hindustan-Tibet Road connecting Shimla with Gartok in Western Tibet]
Uttarakhand
  1. Thaga La
  2. Niti Pass
  3. Lipu Lekh
Sikkim
  1. Nathu La
  2. Jelep La [important trade route connecting Kalimpong (near Darjeeling) with Lhasa in Tibet, passes through Jelep La (4,386 m)]

The Trans Himalayas

  • The Himalayan ranges immediately north of the Great Himalayan range.
  • Also called the Tibetan Himalaya because most of it lies in Tibet.
  • The Zaskar, the Ladakh, the Kailas and the Karakoram are the main ranges.
  • It stretches for a distance of about 1,000 km in east-west direction.
  • Average elevation is 3000 m above mean sea level.
  • The average width of this region is 40 km at the extremities and about 225 km in the central part.
  • The Nanga Parbat (8126 m) is an important range which is in The Zaskar Range.
  • North of the Zaskar Range and running parallel to it is the Ladakh Range. Only a few peaks of this range attain heights of over 6000 metres.
  • The Kailas Range (Gangdise in Chinese) in western Tibet is an offshoot of the Ladakh Range. The highest peak is Mount Kailas (6714 m). River Indus originates from the northern slopes of the Kailas range.
  • The northern most range of the Trans-Himalayan Ranges in India is the Great Karakoram Range also known as the Krishnagiri range.
  • Karakoram Range extends eastwards from the Pamir for about 800 km. It is a range with lofty peaks [elevation 5,500 m and above]. It is the abode of some of the greatest glaciers of the world outside the polar regions.
  • Some of the peaks are more than 8,000 metre above sea level. K2 (8,611 m)[Godwin Austen or Qogir] is the second highest peak in the world and the highest peak in the Indian Union.
  • The Ladakh Plateau lies to the north-east of the Karakoram Range. It has been dissected into a number of plains and mountains [Soda Plains, Aksai Chin, Lingzi Tang, Depsang Plains and Chang Chenmo]

Purvanchal or Eastern Hills

  • Eastern Hills or The Purvanchal are the southward extension of Himalayas running along the north-eastern edge of India.
  • At the Dihang gorge, the Himalayas take a sudden southward bend and form a series of comparatively low hills which are collectively called as the Purvanchal.
  • Purvanchal hills are convex to the west.
  • They run along the India-Myanmar Border extending from Arunachal Pradesh in the north to Mizoram in the south.
Purvanchal - Eastern Himalayas
  • Patkai Bum hills are made up of strong sandstone; elevation varying from 2,000 m to 3,000 m; merges into Naga Hills where Saramati (3,826 m) is the highest peak.
  • Patkai Bum and Naga Hills form the watershed between India and Myanmar.
  • South of Naga Hills are the Manipur hills which are generally less than 2,500 metres in elevation.
  • The Barail range separates Naga Hills from Manipur Hills.
  • Further south the Barail Range swings to west into Jaintia, Khasi and Garo hills which are an eastward continuation of the Indian peninsular block. They are separated from the main block by Ganga and Brahmaputra rivers.
  • South of the Manipur Hills are the Mizo Hills (previously known as the Lushai hills) which have an elevation of less than 1,500 metres. The highest point is the Blue Mountain (2,157 m) in the south.

Syntaxial Bends of the Himalayas

  • Himalayas extend in the east-west direction from the Indus gorge in the west to the Brahmaputra gorge in the east.
  • Himalayan ranges take sharp southward bends at these gorges. These bends are called syntaxial bends of the Himalayas.
  • The western syntaxial bend occurs near the Nanga Parbat where the Indus river has cut a deep gorge.
  • The eastern syntaxial bend occurs near the Namche Barwa
    .

Indian Rock System: Archaean, Purana, Dravidian & Aryan Rock System


Rock System Based on Geological History Of India

  1. The Archaean Rock System.
  2. The Purana Rock System.
  3. The Dravidian Rock System.
  4. The Aryan Rock System.
Rock System - Geological History Of IndiaRock System India

Archaean Rock System (Pre-Cambrian Rocks)

geologic time scale
  • Rocks formed prior to the Cambrian system.
  • The Archaean rock system includes:

Archaean Gneisses and Schists [4 Billion Years]

Gneiss == Mineral composition varies from granite to gabbro.
Schists == mostly crystalline, include mica, talc, hornblende, chlorite, etc.
These rocks are:
  • Oldest rocks [pre-Cambrian era] [formed about 4 billion years ago].
  • Rocks formed due to solidification of molten magma – the earth’s surface was very hot then.
  • Known as the ‘Basement Complex’ [They are the oldest and forms the base for new layers]
  • Azoic or unfossiliferous,
  • Foliated (consisting of thin sheets),
  • Thoroughly crystalline (because they are volcanic in origin),
  • Plutonic intrusions (volcanic rocks found deep inside).

Dharwar System [4 – 1 Billion Years]

  • Formation period ranges from 4 billion years ago to – 1 billion years ago.
  • Highly metamorphosed sedimentary rock-system. [formed due to metamorphosis of sediments of Archaean gneisses and schists].
  • They are the oldest metamorphosed rocks.
  • Found in abundance in the Dharwar district of Karnataka.
  • Economically the most important rocks because they possess valuable minerals like high grade iron-ore, manganese, copper, lead, gold, etc.

Purana Rock System (1400 – 600 Million Years)

  • Includes two divisions: the Cuddapah System and the Vindhyan System.

Cuddapah System

  • Unfossiliferous clay, slates, sandstones and limestones was deposited in synclinal basins [depression between two folds {Fold mountain}].
  • Outcrops best observed in Cuddapah district of Andhra Pradesh.
  • These rocks contain ores of iron, manganese, copper, cobalt, nickel, etc.
  • They contain large deposits of cement grade limestones.

Vindhyan System (1300-600 million years)

  • This system derives its name from the great Vindhyan mountains.
  • The system comprises of ancient sedimentary rocks (4000 m thick) superimposed on the Archaean base.
  • Mostly Unfossiliferous.
  • Large area of this belt is covered by the Deccan trap.
  • The Vindhayan system have diamond bearing regions from which Panna and Golconda diamonds have been mined.
  • It is devoid of metalliferous minerals but provides large quantities of durable stones, ornamental stones, limestone, pure glass making sand etc..

Dravidian Rock System (Palaeozoic)

  • Formed about 600 – 300 million years ago.
  • Found in the Extra Peninsular region (Himalayas and Ganga plain) and are very rare in Peninsular India. [The name ‘Dravidian’ doesn’t mean they are found in South India]
  • Abundant fossils.
  • The rocks of Cambrian, Ordovician, Silurian, Devonian and Carboniferous periods are fall under Dravidian system. (All these are not important, only Carboniferous is important)

Carboniferous rocks (350 million years)

  • The Carboniferous rocks (350 million years) comprise mainly of limestone, shale and quartzite.
  • Mount Everest is composed of Upper Carboniferous limestones.
  • Coal formation started in the Carboniferous age.
  • Carboniferous in geology means coal bearing. [most of the coal found in India is not of Carboniferous period; High quality coal of Great Lakes Region-USA, U.K and Ruhr region is Carboniferous coal].

Aryan Rock System

  • Upper Carboniferous to the Recent.

Gondwana System

  • The Gondwana System [derives its name Gonds, the most primitive people of Telangana and Andhra Pradesh]
  • They are deposits laid down in synclinal troughs on ancient plateau surface.
  • As the sediments accumulated, the loaded troughs subsided.
  • Fresh water and sediments accumulated in these trough and terrestrial plants and animals thrived.
  • This happened since Permian period (250 million years ago).

Gondwana Coal

  • Gondwana rocks contain nearly 98 per cent of India’s coal reserves.
  • Gondwana coal is much younger than the Carboniferous coal and hence it’s carbon content is low.
  • They have rich deposits of iron ore, copper, uranium and antimony also.
  • Sandstones, slates and conglomerates are used as building materials.

Jurassic System

  • The marine transgression in the latter part of the Jurassic gave rise to thick series of shallow water deposits in Rajasthan and in Kuchchh.
  • Coral limestone, sandstone, conglomerates and shales occur in Kuchchh.
  • Another transgression on the east coast of the Peninsula is found between Guntur and Rajahmundry.

Deccan Trap

  • Volcanic outburst over a vast area of the Peninsular India from the end of the Cretaceous till the beginning of the Eocene gave rise to Deccan Traps.
  • Basaltic lava flowed out of fissures covering a vast area of about ten lakh sq km.
  • These volcanic deposits have flat top and steep sides and therefore called ‘trap’ meaning a ‘stair’ or ‘step’ in Swedish.
  • The process of weathering and erosion (denudation) since millions of years has reduced the Deccan Trap to almost half of its original size.
  • Present Deccan Trap covers about 5 lakh sq km mainly in parts of Kuchchh, Saurashtra, Maharashtra, the Malwa plateau and northern Karnataka.
  • Thickness of the Deccan Traps is 3,000 metres along the west which is reduced to 600-800 metres towards the south, 800 metres in Kuchchh and only 150 metres at the eastern limit.
  • The weathering of these rocks for a long time has given birth to black cotton soil known as ‘regur’.
The Deccan Trap has been divided into three groups:

Group

Found in

Inter-trappean beds

Layers of volcanic ash

The Upper TrapMaharashtra and SaurashtraPresentPresent
The Middle TrapCentral India and MalwaVery rare to absentPresent
The Lower TrapPresentVery rare to absent

Tertiary System

  • Eocene to Pliocene about 60 to 7 million years ago.
  • The tertiary is the most significant period in India’s geological history because the Himalayas were born and India’s present form came into being in this period
    .


India: Geographical Extent & Frontiers


India As A Geographical Unit

India latitudinal-longitudinal extent

East-West Extent of Main Land India (Including Pak occupied Kashmir-POK):

68° 7′ east to 97° 25′ east longitude

South-North Extent of Main Land India:

8° 4′ north to 37° 6′ north latitude

Locational Extent:

8° 4′ N to 37° 6′ N latitude and 68° 7′ E to 97° 25′ East longitude.
Jammu and Kashmir - pakistan and china occupied territoriesIndira col-NJ9842-siachen glacier
  • The southernmost point of the country is the Pygmalion Point or Indira Point is located at 6° 45′ N latitude.
  • North-south extent from Indira Col in Kashmir to Kanniyakumari is 3,214 km.
  • East-west width from the Rann of Kachachh to Arunachal Pradesh is 2,933 km.
  • With an area of 32,87,263 sq km, India is the seventh largest country of the world.
  • India accounts for about 2.4 per cent of the total surface area of the world.
10 largest countries in world by area
  • The Tropic of Cancer passes through the middle of the country dividing it into two latitudinal halves.
  • The area to the north of Tropic of Cancer is nearly twice the area which lies to the south of it.
  • South of 22° north latitude, the country tapers off over 800 km into the Indian Ocean as a peninsula.

East-West time difference is nearly 2 hrs.

  • The earth moves [rotation and revolution] around its axis through 360° in 24 hours. Thus, a difference of 1° longitude will make a difference of 4 minutes in time.
  • Therefore the difference of local time between western-most point and eastern-most point is 30 x 4 = 120 minutes or 2 hours.

India, Tropical or Temperate Country?

  • The temperate part (north of Tropic of Cancer) is twice the area of tropical part.
  • But India has always been treated as a tropical country for two different reasons – physical and cultural.

Physical Geographical Reasons

  • The country is separated from the rest of Asia by Himalayas.
  • Its climate is dominated by the tropical monsoons and the temperate air masses are blocked by Himalayas.
  • Entire area south of the Himalayas is essentially tropical from climatic point of view: Although the night temperatures in Winter at several places in North India may come down to the level of those prevailing in temperate lands, yet clear skies and intense insolation raise the day temperatures to a tropical level.

Cultural Geographical Reasons

  • Settlements, diseases, agricultural and primary economic activities are all tropical in nature.
It is primarily because of Himalayas that India is a tropical country.

India’s Frontiers

Data from Ministry Of Home Affairs (Department Of Border Management)
  • India has 15106.7 Km of land border running through 92 districts in 17 States and a coastline of 7516.6 Km [6100 km of mainland coastline + coastline of 1197 Indian islands] touching 13 States and Union Territories (UTs).
  • Barring Madhya Pradesh, Chhattisgarh, Jharkhand, Delhi, Haryana and Telangana, all other States in the country have one or more international borders or a coastline and can be regarded as frontline States from the point of view of border management.
  • India’s longest border is with BANGLADESH while the shortest border is with Afghanistan.
  • The length of India’s land borders with neighboring countries is as under:
india boundary length with neighbours

Border with China

  • This is the second longest border of India, next only to its border with Bangladesh.
  • Five Indian states, namely Jammu and Kashmir, Himachal Pradesh, Uttarakhand, Sikkim and Arunachal Pradesh touch the Indian boundary with China.
  • The Sino-Indian border is generally divided into three sectors namely : (i) the Western sector, (ii) the Middle sector, and (iii) the Eastern sector.

The Western Sector

  • Separates Jammu and Kashmir state of India from the Sinkiang (Xinjiang) province of China.
  • The western sector boundary is largely the outcome of the British policy towards the state of Jammu and Kashmir.
  • China claims the Aksai Chin district, the Changmo valley, Pangong Tso and the Sponggar Tso area of north-east Ladakh as well as a strip of about 5,000 sq km down the entire length of eastern Ladakh.
  • China also claims a part of Huza-Gilgit area in North Kashmir (ceded to it in 1963 by Pakistan).

The Middle Sector

  • Two Indian states of Himachal Pradesh and Uttarakhand touch this border.

The Eastern Sector

  • The 1,140 km long boundary between India and China runs from the eastern limit of Bhutan to a point near Diphu pass (Talu Pass) at the trijunction of India, Tibet and Myanmar.
  • This line is usually referred to as the Mc Mahon Line after Sir Henry Mc Mahon, then foreign secretary of British India, who negotiated the boundary agreement between Great Britain and Tibet at Shimla accord in 1913-14.

The India-Nepal Boundary

  • Five states of India, namely Uttarakhand, Uttar Pradesh, Bihar, West Bengal and Sikkim touch the Nepalese border with India. The border is a porous one with unrestricted movement of goods and people between Indian and Nepal.
  • Major portion of Indo-Nepalese border runs in the east-west direction almost along the foothill of the Shiwalik Range.

The India-Bhutan Boundary

  • Quite peaceful border and there is no boundary dispute between the two countries.

The Indo-Pakistan Boundary

  • The Indo-Pakistan boundary is the result of partition of the country in 1947 under the Radcliffe award of which Sir Cyril Radcliffe was the chairman.
  • Jammu and Kashmir, Sir Creek are the major disputed regions.
Sir Creek - india pakistan disputed

The India-Bangladesh Border

  • India’s 4,096 km long border with Bangladesh is the longest.
  • This boundary has been determined under the Radcliffe Award which divided the erstwhile province of Bengal into two parts.

India-Myanmar Boundary

  • This boundary runs roughly along the watershed between the Brahmaputra and Ayeyarwady [Irrawaddy].
  • It passes through thickly forested regions, with Mizo Hills, Manipur and Nagaland on the Indian side and Chin Hills, Naga Hills and Kachin state on the Myanmar side.

India-Sri Lanka Boundary

  • India and Sri Lanka are separated from each other by a narrow and shallow sea called Palk Strait.
  • Dhanushkodi on the Tamil Nadu coast in India is only 32 km away from Talaimanar in Jaffna peninsula in Sri Lanka. These two points are joined by a group of islets forming Adam’s Bridge
    .