Comprehensive Indian Physical Geography Notes for UPSC covering physiography, Himalayas, rivers, climate, soils, natural vegetation, coastal plains, islands, maps, diagrams, PYQs, and regularly updated exam-oriented study material.
Physiography of India
Origin and Evolution of Himalayas
The Himalayas, one of the world youngest and highest mountain ranges were formed due to tectonic process involving the collision of Indo-Australian plate with Eurasian plate. Their origin and evolution are the result of complex geological events spanning millions of years, shaped by plate tectonics, crustal deformation and erosion.
Origin of Himalayas
Tectonic Setting (Pre Collision)
Around 200 million years ago the Indian plate was part of super continent, located near the southern edge of ancient Tethys sea.
During Jurassic period, about 150 million years ago Gondwana began to break apart and the Indian plate started drifting northward.
About 100 million years ago, the Tethys ocean was subducting beneath the southern margin of Eurasian plate.
Initial Collision (50 to 55 million years ago)
Around 50 to 55 million years ago early Eocene, Indian plate collided with Eurasian plate, marking the onset of Himalayan orogeny.
Tethys ocean close as the continental crust of Indian plate began to push against Eurasian plate, initiating the uplift of proto Himalayas.
The collision was not abrupt, it involved the scraping of oceanic sediments and volcanic rocks, forming the initial Himalayan foot hills.
Evolution of Himalayas
Early Phase (50 to 30 million years ago)
The collision caused intense folding due to abduction process, formation of Indo-Tsangpo-Suture Zone, formation of greater Himalaya.
Middle Phase (30 to 10 million years ago)
Formation of main central thrust to the south of greater Himalayas, upliftment of middle Himalayas. South to middle Himalayas main boundary thrust was formed.
Late Phase (10 million years ago to present)
Formation of Shivalik and formation of Himalayan frontal fault between Shivalik and plains.
At present Himalayas are still rising. These are young folded mountains. These are about 2400km long between Nanga Parbat in Jammu and Kashmir to Namcha Barwa in Arunachal Pradesh.
Latitudinal Division of Northern Himalayas
These are mainly classified into
Trans Himalayas
The Himalayas
Trans Himalayas
Trans Himalayas extends north to Himalayas and south of Tibet. It has 3 parallel ranges
Karakoram Range
It is about 500 km long. Its highest peak is K2/ Godwin Austin (second highest peak of the world.)
K2 is highest peak of India.
Ladakh Range
It extends south of Karakulam. It is smallest among all.
Zanskar Range
It extends south of Ladakh; between Ladakh and Zanskar, Indus river flows. It is about 300km long.
The Himalayas
Himalayas has three parallel ranges
Greater Himalayas
Its average altitude is greater than 6000m.
Its highest peak is Mt. Everest in Nepal followed by Kanchenjunga in Sikkim i.e. highest peak of Himalaya in India, 8586m. Makalu and Annapurna are other important peaks.
It extends about 2400km between Pakistan, India, China, Nepal and Bhutan.
Greater Himalaya have old lake deposit which are found at high altitude. These are locally called Karewa. This Karewa soil is used for saffron cultivation.
Greater Himalayas is abode of glaciers from where numerous river originates e.g. Gangotri, Yamunotri, and Pindari, etc.
Middle Himalayas
Middle Himalayas are also known as Lesser Himalayas.
It extends south to Greater Himalayas.
It is divided into number of ranges, valleys, located between middle of Greater Himalayas include Kashmir valley and Kathmandu valley.
The ranges of Middle Himalaya include
Pir Punjab Range
It separate Jammu from Kashmir.
It paved way to National Highway 44, newly constructed railways, Mata Vaishno Devi and Patnitop hill station.
Dhauladhar Range
It is in Himachal Pradesh.
It is famous for hill station and apple cultivation.
Nag Tibba Hills
Nag Tibba range is famous for its scenic beauty and tracking enthusiast.
Missouri Hills
It is Uttarakhand.
It is called Queen of hills because of presence of beautiful hill stations.
Mahabharat Range
It extends mainly in Nepal. Kathmandu valley lie between Mahabharat range and Greater Himalaya.
Dafla Hills, Miri Hills, Abor Hills and Mishmi Hills
These are known of Middle Himalaya in Arunachal Pradesh.
Shivalik Hills
It is youngest among all three ranges.
The valleys between Himalaya and Shivalik are called Duns in the west e.g. Dehradun, Paatlidun and Dwar in the east e.g. Haridwar, Kotdwar, etc.
Shivalik also divided into multiple ranges like
Jammu Hills- Jammu
Dudhwa Hills- Uttar Pradesh
Churia Hills - Nepal India (Uttar Pradesh) border
Someshwar Hills - Nepal, India (Bihar) border
Longitudinal Division of Northern Himalayas
Kashmir Himalayas
It is also called Punjab Himalaya.
It extends between Indus river in the west to Satluj river in the east.
It include Greater Himalaya of Jammu and Kashmir, Himachal, Vir Punjab Range and Dhauladhar range and the Jammu hills of Shivalik.
It is origin point of numerous rivers including Chenab, Ravi, Vyas and Jhelum.
Kumaon Himalayas
It extends between Satluj river in the west to Kali river in the east.
It includes Greater Himalaya, Nag Tibba hills and Missouri Hills.
It is world famous for its hill stations and glaciers like Gangotri, Yamunotri and Milan, Gaumukh glacier.
Ganga, Yamuna and Alaknanda originates from here.
Nepal Himalayas
It is longest Himalayas.
It extends between Kali river in west to Teesta river in east.
It contains money highest peak including Mt. Everest and Kanchenjunga.
It has Kathmandu valley and Pokhara valley.
Various river pass through this like Ghagra, Gandak, and Kosi.
Assam Himalayas
It is second longest.
It is famous for its biological hotspot status.
It extends from Teesta to Brahmaputra river.
Important Passes in Himalayas
Pass
Location
Importance
Khardung La Pass
Ladakh
One of the highest motorable pass
Zojila Pass
Ladakh
It connect Srinagar to Lah
Banihal Pass
Jammu and Kashmir
Connects Srinagar to Lah
Burzil Pass
Jammu and Kashmir
Connect Kashmir with PoJK
Baralacha Pass
Himachal Pradesh
Connects Himachal to Tibet
Lipu Lake
Uttrakhand
Connect Kailash Mansarovar
Mana Pass
Uttrakhand
Connects India with Tibet
Niti Pass
Uttrakhand
Connects India with Tibet
Nathula Pass
Sikkim
Connects India with Tibet
Jelep Pass
Sikkim
Connects India with Tibet
Bomdila Pass
Arunachal Pradesh
Connects India with Tibet
Sela Pass
Arunachal Pradesh
Connects Tezpur of Assam to Tawang of Arunachal Pradesh
Plains
North Indian plains also known as Indo-Gangetic plains or Great Plains of India, represents youngest and most fertile physiographic division of country.
It is spanning over approximately 7 to 7.8 lac km2. They extend over 3200km including Pakistan and 2400km within India. It extends from arid region of western Rajasthan to the moist region of Brahmaputra valley in east. It has average width of 150 to 300kms. It is located between Himalayas in north and peninsular plateau in the south.
Origin of North Indian Plain
The origin of these plain traced back to the tertiary period when the convergence of Indian and Eurasian tectonic plate caused the uplift of the Himalayas, creating a deep tectonic depression or syncline between the rising Himalayas and peninsular plateau.
This depression was further accentuated by isostatic adjustments and down warping, particularly in the Gangetic plain between Rajmahal hills of Chhota Nagpur plateau and Garo hills of Meghalaya.
Over the last 2.5 million years Ganga, Brahmaputra and Indus river have filled entire depression by using their sediments.
Classification of North Indian Plains
The classification of north Indian plains is two fold
Physiographic Division
It is based on soil types and the age of alluvial. This includes
It is based on dominant river system. These are divided into following
Rajasthan Plains
It cover nearly about 1.75 lac km2 west of Aravalli range. This region is called Marusthali. This part receives rainfall less than 50 cm per annum. Luni river is the most dominant river of the region which form inland drainage system. This region is facing problem of soil salinity and expansion of desert.
East of Aravalli is called Banasthali. It receives more than 50cm to 75cm per annum. Most dominant river in north, Mahi and Sabarmati river, in the south. This region is known for its high soil fertility that's why it support large number of population. Problem in this region is soil erosion done by Chambal river.
Punjab-Haryana Plain
About 600km long and 300km wide plain which extends north and east of Rajasthan and mainly west of Aravalli. It is land of five doab which include Sindhu Sagar doab, Chaj doab, Rechna doab, Bari doab and Bist doab. It is region of green revolution but facing problem of increasing alkalinity in the soil, soil erosion by local rivers and demising result due to high use of fertilizers and chemical compounds in the past.
Ganga Plain
It is about 1400km long and 300km wide from Delhi to West Bengal, Kolkata. It is sub-divided into three parts:-
Upper Ganga Plain
It covers western UP, Ganga-Yamuna doab, Rohilkhand and Bundelkhand. It is the region of high soil fertility specially in Ganga-Yamuna doab but low fertility in Bundelkhand. The region include Kanpur, Kanoj, Saranpur, Mathura, Agra, etc.
Mid Ganga Plain
It covers eastern UP to Bihar. It features thick alluvial that's why high fertility. It covers larger part of Awadh plain in the north to Ganga that includes Gorakhpur, Prayagraj, Chapra and Varanasi, etc. south to Ganga it includes Mirzapur, Chitrakoot, Mughalsarai, etc.
Lower Ganga Plain
It includes larger part of Bihar and West Bengal. It is also known for high fertility. In the lower Ganga plain, Ganga river bifurcates. Its distributary is called Hooghly and that flows through West Bengal.
Brahmaputra Plain
It is about 720km long and 80Km wide, surrounded by eastern Himalayas and hills. It features multiple riverine alluvial island and vast alluvial plain. It is high flood prone area that's why its fertility is so high.
Plateaus
Deccan Plateau
Deccan Plateau has three main division
Maharashtra Plateau
Maharashtra Plateau form the northern part of Deccan plateau, primarily laying within the state of Maharashtra.
It has volcanic origin. It was formed due to volcanic eruption, which had taken place during cretaceous period, about 65 million years ago.
Due to this volcanic eruption Deccan traps were formed. It is a thick sequence of basaltic lava
It is drained by Godavari, Bhima and Krishna rivers.
It is known for its fertile black soil, which supports almost every type of crop.
Telangana Plateau
It is situated primarily within Telangana state.
It was also formed through volcanic eruption.
This is drained by Godavari, Krishna and Moosi river.
It is very rich in iron ore, limestone and coal.
Karnataka Plateau
It lies in the southern part of Deccan plateau.
It extends in Karnataka and Tamil Naidu primarily.
It is drained by Kaveri and Tungabhadra river.
It is very rich in gold, iron ore and limestone.
Central Highlands
Chhota Nagpur Plateau
It is richest among all central highland plateau.
It has oldest rock in India about 2.5 billion year old (The first which came out of sea).
Its rocks include Dharwad and Gondwana rock series.
It is drained by Damodar river, Subanrekha river, North Koel and south Koel river.
It is rich in coal (Gondwana rocks series) and iron ore (Dharwad rock series).
Other minerals are Mica, Bauxite and Uranium.
Meghalaya Plateau
Meghalaya plateau is extension of Chhota Nagpur plateau.
It is divided into three parts
Karo
Kasi
Jaintia
Shillong is the highest point.
Cherapunji and Mawsin ramp are situated in Kasi hills.
It is drained by southern tributers of Brahmaputra.
It is rich in coal, limestone and sillimanite.
Marwar Plateau
It lies in western Rajasthan, west to Aravalli.
It is predominately a sandy plain that includes bad land.
It is drained by Luni river primarily and other seasonal rivers.
It is rich in gypsum, lignite, gems and sandstone.
Madhya Bharat Pathar
It covers south-east Rajasthan and north-western Madhya Pradesh.
It is spread east to Aravalli range.
It is drained by Chambal and Betwa river.
It is rich in limestone, diamonds (Panna).
Bundelkhand Plateau
Bundelkhand plateau lies east to Madhya Bharat Pathar and Malwa plateau.
It is composed of Bundelkhand gneiss, it is India's oldest rock.
It is drained by Betwa and Ken river.
It is rich diamonds, granite and sandstone.
Baghelkhand Plateau
It is between bundelkhand and Chhota Nagpur plateau.
It lies in the north-eastern Madhya Pradesh.
It is drained by Son, Rewa and northern tributaries of Mahanadi.
It is rich in bauxite, coal and limestone.
Malwa Plateau
It lies in north-western Madhya Pradesh and south-eastern Rajasthan.
It is drained by Chambal river and Narmada and Mahi river.
It is rich in limestone and sandstone.
It is also arid plateau.
Mountains and Hills of Peninsular India
Aravalli Hills
Aravalli range is one of the oldest mountain range in the world stretching approximately for 800kms from Gujrat to Delhi across Indian states of Gujrat, Rajasthan, Haryana and Delhi.
Its highest peak is Guru Shikhar in Sirohi district of Rajasthan.
It is an example of old folded mountains.
It was formed about 1.8 to 2.5 billion years ago that's why it is considered as one of the oldest mountain range in the world.
It forms barrier between Thar desert and the fertile easter Rajasthan.
It is very rich in marble, granite, zinc, cooper and talc.
It is origin point of number of rivers like Luni, Sabarmati, Mahi, etc.
Vindhyan Range
It is about 1050km long east to west running mountain.
It is an example of block mountain
Its highest peak is Sadbhavna Shikhar (Amarkantak).
It form northern edge of peninsular India.
It was formed about 1.6 to 1 billion years ago.
Number of rivers originates from here like Son, Ken, Betwa, Chambal, etc.
It is rich in various minerals like limestone, bauxite, sandstone and diamond mine in Panna.
Satpura Range
It is about 900km long range runs parallel to Vindhyan range. These two ranges are separated by Narmada rift valley.
It is example of horst.
Its highest peak is Dhupgarh in Pachmarhi, Madhya Pradesh.
Gawaligarh hills, Mahadev hills are its branches/ part.
It was formed during 65 to 60 million years ago during Narmada Tapi rift valley formation.
Number of rivers originates from here like Hiren, Tawa, etc.
It is rich in coal, manganese, bauxite, limestone, copper.
Western Ghats
Western Ghats extends from Gujrat to Tamil Nadu via Maharashtra, Goa, Karnataka and Kerala.
It is about 1600km long parallel to Arabian Sea.
Its highest peak in Anamudi (2695m) it is Anamali hills, Kerala.
It is known with different names with different parts.
Sahyadri Hills
Mainly in Gujrat, Maharashtra and Goa.
It has two famous peaks
Kalsubai, Nasik (Godavari originates nearby)
Mahabaleshwar, Satara (Origin point of Krishna).
Sahyadri Hills has two important passes
Thal Ghat (Mumbai to Nasik)
Bhor Ghat (Mumbai to Pune)
Nilgiri Hills
It is called in Karnataka and Tamil Nadu mainly.
Highest peak of Nilgiri is Doddabetta. It is in Tamil Nadu
At Nilgiri Eastern Ghat join Western Ghat in Tamil Nadu
Nilgiri is famous for Tea.
Annamalai
It is separated from Nilgiri by Palghat gap.
It is about 80km wide through this south-west enter into Karnataka and rains over Udupi, Bangalore and parts of western Tamil Nadu.
Annamalai extends into Tamil Nadu and Kerala.
Its highest peak is Anamudi and it lies in Kerala.
Cardamom Hills
Cardamom hills are separated from Annamalai hills by Shencottah Gap.
The highest peak of Cardamom hills is Agasthyamalai.
Cardamon hill is famous for cultivation of cardamom.
Eastern Ghats
Eastern ghats are example of old folded mountain.
Its average length is about 1500km and it runs parallel to Bay of Bengal.
It extends from Odisha to Tamil Nadu via Andhra Pradesh and parts of Karnataka.
Its highest peak is Mahendra Giri which lies in Odisha.
It is rich in bauxite, manganese, iron ore.
It is also famous for its red sanders trees which are found Seshachalam and Nalla Malla hills.
India's 50% bauxite and 95% chromite comes eastern ghats.
Rajmahal Hills
It is about 200km long extends mainly only in Jharkhand and West Bengal border.
It lies 90% in Jharkhand and 10% in West Bengal.
It was outcome of volcanic activity that's why it also called Rajmahal trap also.
It is rich in coal, China clay and uranium.
Rajmahal Gharogap
It is gap between Rajmahal hills in the west and Gharo hills in the east (Meghalaya Plateau).
It extends about 400km east to west.
It was formed due to upliftment of Shillong plateau when Indian plate hit and compressed against Eurasian plate in the east about 50 to 30 million years ago.
It has now a fertile soil which supports second most densely populated state of India.
It is separated from Satpura range by Tapi rift valley
It is very famous for its dense forest cover.
It is rich in coal, iron ore and bauxite
Coastal Plain of India
Indian coast line is 11098.81 km. It is up from previous 7516 km due to update calculation methodologies and higher resolution geospatial mapping. This revised total consist of 7870.51 km of mainland coast line and 3228.30 km of island territories.
