Peninsular Plateau (Deccan Plateau) | Plateaus in the Peninsular Region

Table of Contents

• Peninsular Plateau
  • Features of the Peninsular Plateau
• Minor Plateaus in the Peninsular Plateau
  • Marwar Plateau or Mewar Plateau
  • Central Highland
  • Bundelkhand Upland
  • Malwa Plateau
  • Baghelkhand
  • Chotanagpur Plateau
  • Meghalaya Plateau
• Deccan Plateau
  • Maharashtra Plateau
  • Karnataka Plateau
  • Telangana plateau
  • Chhattisgarh PlainShareWhatsAppTweetEmail

Peninsular Plateau

Features of the Peninsular Plateau

• Roughly triangular in shape with its base coinciding with the southern edge of the great plain of North India. Apex of the triangular plateau is at Kanniyakumari.
• It covers a total area of about 16 lakh sq km (India as a whole is 32 lakh sq km).
• The average height of the plateau is 600-900 m above sea level (varies from region to region).
• Most of the peninsular rivers flow west to east indicating it’s general slope.
• Narmada-Tapti are the exceptions which flow from east to west in a rift (rift is caused by divergent boundary (Go back to Interaction of plates).
• The Peninsular Plateau is a one of the oldest landforms of earth.
• It is a highly stable block composed mostly of the Archaean gneisses and schists {Rock System}.
• It has been a stable shield which has gone through little structural changes since its formation.
• Since few hundred million years, Peninsular block has been a land area and has never been submerged beneath the sea except in a few places.
• Peninsular Plateau is an aggregation of several smaller plateaus, hill ranges interspersed with river basins and valleys.

Minor Plateaus in the Peninsular Plateau

Marwar Plateau or Mewar Plateau

• It is the plateau of eastern Rajasthan. [Marwar plain is to the west of Aravalis whereas Marwar plateau is to the east].
• The average elevation is 250-500 m above sea level and it slopes down eastwards.
• It is made up of sandstone, shales and limestones of the Vindhayan period.
• The Banas river, along with its tributaries [Berach river, Khari rivers] originate in the Aravali Range and flow towards northwest into Chambal river. The erosional activity of these rives make the plateau top appear like a rolling plain.

[Rolling Plain: ‘Rolling plains’ are not completely flat: there are slight rises and fall in the land form. Ex: Prairies of USA]

Central Highland

• Also called the Madhya Bharat Pathar or Madhya Bharat Plateau.
• It is to the east of the Marwar or Mewar Upland.
• Most of plateau comprises the basin of the Chambal river which flows in a rift valley.
• The Kali Sindh, flowing from Rana Prataph Sagar, The Banas flowing through Mewar plateau and The Parwan and the Parbati flowing from Madhya Pradesh are its main tributaries.
• It is a rolling plateau with rounded hills composed of sandstone. Thick forests grow here.
• To the north are the ravines or badlands of the Chambal river [They are typical to Chambal river basin]{ Arid landforms}.

Bundelkhand Upland

• Yamuna river to the north, Madhya Bharat Pathar to the west, Vindhyan Scarplands to the east and south-east and Malwa Plateau to the south.
• It is the old dissected (divided by a number of deep valleys) upland of the ‘Bundelkhand gneiss’ comprising of granite and gneiss.
• Spreads over five districts of Uttar Pradesh and four districts of Madhya Pradesh.
• Average elevation of 300-600 m above sea level, this area slopes down from the Vindhyan Scarp toward the Yamuna River.
• The area is marked by a chain of hillocks (small hill) made of granite and sandstone.
• The erosional work of the rivers flowing here have converted it into an undulating (wave like surface) area and rendered it unfit for cultivation.
• The region is characterized by senile (characteristic of or caused by old age) topography.
• Streams like Betwa, Dhasan and Ken flow through the plateau.

Malwa Plateau

• The Malwa Plateau roughly forms a triangle based on the Vindhyan Hills, bounded by the Aravali Range in the west and Madhya Bharat Pathar to the north and Bundelkhand to the east.
• This plateau has two systems of drainage; one towards the Arabian sea (The Narmada, the Tapi and the Mahi), and the other towards the Bay of Bengal (Chambal and Betwa, joining the Yamuna).
• In the north it is drained by the Chambal and many of its right bank tributaries like the Kali, the Sindh and the Parbati. It also includes the upper courses of the Sindh, the Ken and the Betwa.
• It is composed of extensive lava flow and is covered with black soils.
• The general slope is towards the north [decreases from 600 m in the south to less than 500 m in the north]
• This is a rolling plateau dissected by rivers. In the north, the plateau is marked by the Chambal ravines.

Baghelkhand

• North of the Maikal Range is the Baghelkhand.
• Made of limestones and sandstones on the west and granite in the east.
• It is bounded by the Son river on the north.
• The central part of the plateau acts as a water divide between the Son drainage system in the north and the Mahanadi river system in the south.
• The region is uneven with general elevation varying from 150 m to 1,200 m.
• The Bhanrer and Kaimur are located close to the trough-axis.
• The general horizontality of the strata shows that this area has not undergone any major disturbance.

Chotanagpur Plateau

• Chotanagpur plateau represents the north-eastern projection of the Indian Peninsula.
• Mostly in Jharkhand, northern part of Chhatisgarh and Purulia district of West Bengal.
• The Son river flows in the north-west of the plateau and joins the Ganga.
• The average elevation of the plateau is 700 m above sea level.
• This plateau is composed mainly of Gondwana rocks.
• The plateau is drained by numerous rivers and streams in different directions and presents a radial drainage pattern. {Drainage Pattern}
• Rivers like the Damodar, the Subarnrekaha, the North Koel, the South Koel and the Barkar have developed extensive drainage basins.
• The Damodar river flows through the middle of this region in a rift valley from west to east. Here are found the Gondwana coal fields which provide bulk of coal in India.
• North of the Damodar river is the Hazaribagh plateau with an average elevation of 600 m above mean sea level. This plateau has isolated hills. It looks like a peneplain due to large scale erosion.
• The Ranchi Plateau to the south of the Damodar Valley rises to about 600 m above mean sea level. Most of the surface is rolling where the city of Ranchi (661 m) is located.
• At places it is interruped by monadnocks (an isolated hill or ridge of erosion-resistant rock rising above a peneplain. Ex: Ayers Rock in Australia) and conical hills.
• The Rajmahal Hills forming the north eastern edge of the Chotanagpur Plateau are mostly made of basalt and are covered by lava flows {Basaltic Lava}.
• They run in north-south direction and rise to average elevation of 400 m (highest mount is 567 m). These hills have been dissected into separate plateaus.

Meghalaya Plateau

• The peninsular plateau extends further east beyond the Rajmahal hills to from Meghalaya or the Shillong plateau.
• Garo-Rajmahal Gap separates this plateau from the main block.
• This gap was formed by down-faulting (normal fault: a block of earth slides downwards). It was later filled by sediments deposited by the Ganga and Brahmaputa.
• The plateau is formed by Archaean quartzites, shales and schists.
• The plateau slopes down to Brahmaputra valley in the north and the Surma and Meghna valleys in the south.
• Its western boundary more or less coincides with the Bangladesh border.
• The western, central and the eastern parts of the plateau are known as the Garo Hills (900 m), the Khasi-Jaintia Hills (1,500 m) and the Mikir Hills (700 m).
• Shillong (1,961 m) is the highest point of the plateau.

Deccan Plateau

• It covers an area of about five lakh sq km.
• It is triangular in shape and is bounded by the Satpura and the Vindhya in the north-west, the Mahadev and the Maikal in the north, the Western Ghats in the west and the Eastern Ghats in the east.
• Its average elevation is 600 m.
• It rises to 1000 m in the south but dips to 500 m in the north.
• Its general slope is from west to east which is indicated by the flow of its major rivers.
• Rivers have further subdivided this plateau into a number of smaller plateaus.

Maharashtra Plateau

• The Maharashtra Plateau lies in Maharashtra.
• It forms the northern part of the Deccan Plateau.
• Much of the region is underlain by basaltic rocks of lava origin [Most of the Deccan Traps lies in this region].
• The area looks like a rolling plain due to weathering.
• The horizontal lava sheets have led to the formation of typical Deccan Trap topography [step like].
• The broad and shallow valleys of the Godavari, the Bhima and the Krishna are flanked [bordered on the opposite sides] by flat-topped steep sided hills and ridges.
• The entire area is covered by black cotton soil known as regur.

Karnataka Plateau

• The Karnataka Plateau is also known as the Mysore plateau.
• Lies to the south of the Maharashtra plateau.
• The area looks like a rolling plateau with an average elevation of 600-900 m.
• It is highly dissected by numerous rivers rising from the Western Ghats.
• The general trend of the hills is either parallel to the Western Ghats or across it.
• The highest peak (1913 m) is at Mulangiri in Baba Budan Hills in Chikmaglur district.
• The plateau is divided into two parts called Malnad and Maidan.
• The Malnad in Kannada means hill country. It is dissected into deep valleys covered with dense forests.
• The Maidan on the other hand is formed of rolling plain with low granite hills.
• The plateau tapers between the Western Ghats and the Eastern Ghats in the south and merges with the Niligiri hills there.

Telangana plateau

• The Telangana plateau consists of Archaean gneisses.
• It’s average elevation is 500-600 m.
• The southern part is higher than its northern counterpart.
• The region is drained by three river systems, the Godavari, the Krishna and the Penneru.
• The entire plateau is divided into Ghats and the Peneplains (a vast featureless, undulating plain which the last stage of deposition process).

Chhattisgarh Plain

• The Chhattisgarh plain is the only plain worth the name in the Peninsular plateau.
• It is a saucer shaped depression drained by the upper Mahanadi.
• The whole basin lies between the Maikala Range and the Odisha hills.
• The region was once ruled by Haithaivanshi Rajputs from whose thirty six forts (Chhattisgarh) it derives its name.
• The basin is laid with nearly horizontal beds of limestone and shales.
• The general elevation of the plain ranges from 250 m in the east to 330 m in the west
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Divisions of Indo-Gangetic-Brahmaputra Plains

Table of Contents

• Regional Divisions of the Indo-Gangetic-Brahmaputra Plains [Great Plains]
  • Sindh Plain [Pakistan]
  • Rajasthan Plain
    • Saline Lakes
  • Punjab Plain
  • Ganga Plain
  • Ganga-Brahmaputra Delta
  • Brahmaputra Plain
• Significance of the PlainShareWhatsAppTweetEmail

Regional Divisions of the Indo-Gangetic-Brahmaputra Plains [Great Plains]

1. Sindh Plain
2. Rajasthan Plain.
3. Punjab Plain.
4. Ganga Plain.
5. Brahmaputra Plain.
6. Ganga – Brahmaputra Delta

Sindh Plain [Pakistan]

• Mainly formed of Bhangar Plains.
• Dhors: Long narrow depressions which are the remnants of the course of former rivers.
• Dhand: Alkaline lakes on some dhors.

Rajasthan Plain

• Occupied by Thar or the Great Indian Desert.
• This plain is an undulating plain [wave like] whose average elevation is about 325 m above mean sea level.
• The desert region is called Marusthali and forms a greater part of the Marwar plain.
• It has a few outcrops of gneisses, schists and granites which proves that geologically it is a part of the Peninsular Plateau. It is only at the surface that it looks like an aggradational plain.
• In general, the eastern part of the Marusthali is rocky while its western part is covered by shifting sand dunes locally known as
• The eastern part of the Thar Desert up to the Aravali Range is a semi-arid plain known as Rajasthan Bagar.
• It is drained by a number of short seasonal streams originating from the Aravali and supports agriculture in some patches of fertile tracts.
• Luni is an important seasonal stream which flows into Rann of Kuchchh. The tract north of the Luni is known as thali or sandy plain.

Saline Lakes

• North of the Luni, there is inland drainage having several saline lakes. They are a source of common salt and many other salts.
• Sambhar, Didwana, Degana, Kuchaman, etc. are some of the important lakes. The largest is the Sambhar lake near Jaipur.

Punjab Plain

• This plain is formed by five important rivers of Indus system.
• The plain is primarily made up of ‘doabs’ —the land between two rivers.
• The depositional process by the rivers has united these doabs giving an homogenous appearance.
• Punjab literally means “(The Land of) Five Waters” referring to the following rivers: the Jhelum, Chenab, Ravi, Sutlej, and Beas.
• The total area of this plain is about 1.75 lakh sq km.
• The average elevation of the plain is about 250 m above mean sea level.
• The eastern boundary of Punjab Haryana plain is marked by subsurface Delhi-Aravali ridge.
• The northern part of this plain [Shiwalik hills] has been intensively eroded by numerous streams called Chos. This has led to enormous gullying [Arid Landforms].
• To the south of the Satluj river there is Malwa plain of Punjab.
• The area between the Ghaggar and the Yamuna rivers lies in Haryana and often termed as ‘Haryana Tract’. It acts as water-divide between the Yamuna and the Satluj rivers.
• The only river between the Yamuna and the Satluj is the Ghaggar which is considered to be the present day Successor of the legendary Saraswati River

Ganga Plain

• This is the largest unit of the Great Plain of India stretching from Delhi to Kolkata (about 3.75 lakh sq km).
• The Ganga along with its large number of tributaries originating in the Himalayans have brought large quantities of alluvium from the mountains and deposited it here to build this extensive plain.
• The peninsular rivers such as Chambal, Betwa, Ken, Son, etc. joining the Ganga river system have also contributed to the formation of this plain.
• The general slope of the entire plain is to the east and south east.
• Rivers flow sluggishly in the lower sections of Ganges as a result of which the area is marked by local prominences such as levees, bluffs, oxbow lakes, marshes, ravines, etc. {Fluvial Landforms, Arid Landfroms}
• Almost all the rivers keep on shifting their courses making this area prone to frequent floods. The Kosi river is very notorious in this respect. It has long been called the ‘Sorrow of Bihar’.

Regional divisions of Ganga plains

• Rohilkhand plains
• Avadh Plains
• Mithila Plain
• Magadh Plain.

Ganga-Brahmaputra Delta

• This is the largest delta in the world.
• The Ganga river divides itself into several channels in the delta area. The slope of the land here is a mere 2 cm per km. Two thirds of the area is below 30 m above mean sea level. [Highly vulnerable to sea level changes]
• The seaward face of the delta is studded with a large number of estuaries, mud flats, mangrove swamps, sandbanks, islands and forelands.
• Large part of the coastal delta is covered tidal forests. These are called the Sunderbans because of the predominance of Sundri tree here.

Brahmaputra Plain

• This is also known as the Brahmaputra valley or Assam Valley or Assam Plain as most of the Brahmaputra valley is situated in Assam.
• Its western boundary is formed by the Indo-Bangladesh border as well as the boundary of the lower Ganga Plain. Its eastern boundary is formed by Purvanchal hills.
• It is an aggradational plain built up by the depositional work of the Brahmaputra and its tributaries.
• The innumerable tributaries of the Brahmaputra river coming from the north form a number of alluvial fans. Consequently, the tributaries branch out in many channels giving birth to river meandering leading to formation of bill and ox-bow lakes.
• There are large marshy tracts in this area. The alluvial fans formed by the coarse alluvial debris have led to the formation of terai or semi-terai conditions.

Significance of the Plain

• This one fourth of the land of the country hosts half of the Indian population.
• Fertile alluvial soils, flat surface, slow moving perennial rivers and favorable climate facilitate intense agricultural activity.
• 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 entire plain except the Thar Desert, has a close network of roads and railways which has led to large scale industrialization and urbanization.
• Cultural tourism: There are many religious places along the banks of the sacred rivers like the Ganga and the Yamuna which are very dear to Hindus. Here flourished the religions of Budha and Mahavira and the movements of Bhakti and Sufism
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Indo-Gangetic-Brahmaputra Plain | Bhabar, Terai, Bhangar, Khadar

Table of Contents

• Formation of Indo – Gangetic – Brahmaputra Plain
  • Formation of Indo – Gangetic – Brahmaputra trough
  • Depositional Activity
  • New rivers and more alluvium
• Features of Indo – Gangetic – Brahmaputra Plain
• Geomorphological features of Indo – Gangetic – Brahmaputra Plain
  • The Bhabar
  • The Terai
  • The Bhangar
  • The Khadar
  • Reh or KollarShareWhatsAppTweetEmail

Formation of Indo – Gangetic – Brahmaputra Plain

• The formation of Indo-Gangetic plain is closely related to the formation of Himalayas.

Formation of Indo – Gangetic – Brahmaputra trough

• The rivers which were previously flowing into Tethys sea (Before Indian Plate collided with Eurasian Plate – continental drift, plate tectonics) deposited huge amount of sediments in the Tethys Geosyncline. [Geosyncline – a huge depression]
• Himalayas are formed out of these sediments which were uplifted, folded and compressed due to northern movement of Indian Plate.
• Northern movement of Indian Plate also created a trough to the south of Himalayas.

Depositional Activity

• During the initial stages of upliftment of sediments, the already existing rivers changed their course several times and they were rejuvenated each time (perpetual youth stage of rivers {Fluvial Landforms}).
• The rejuvenation is associated with intense headward and vertical downcutting of the soft strata overlying the harder rock stratum.
• Headward erosion and vertical erosion of the river valley in the initial stages, lateral erosion in later stages contributed huge amount of conglomerates (detritus)(rock debris, silt, clay etc.) which were carried downslope.
• [Head ward erosion == Erosion at the origin of a stream channel, which causes the origin to move back away from the direction of the stream flow, and so causes the stream channel to lengthen]
• These conglomerates were deposited in the depression (Indo-Gangetic Trough or Indo-Gangetic syncline) (the base of the geosyncline is a hard crystalline rock) between peninsular India and the convergent boundary (the region of present day Himalayas).

New rivers and more alluvium

• The raising of Himalayas and subsequent formation of glaciers gave rise to many new rivers. These rivers along with glacial erosion {Glacial Landforms}, supplied more alluvium which intensified the filling of the depression.
• With the accumulation of more and more sediments (conglomerates), the Tethys sea started receding.
• With passage of the time, the depression was completely filled with alluvium, gravel, rock debris (conglomerates) and the Tethys completely disappeared leaving behind a monotonous aggradational plain.
• [monotonous == featureless topography; aggradational plain == plain formed due to depositional activity. Indo-Gangetic plain is a monotonous aggradational plain formed due to fluvial depositions].
• Upper peninsular rivers have also contributed to the formation of plains, but to a very small extent.
• During the recent times (since few million years), depositional work of three major river systems viz., the Indus, the Ganga and the Brahmaputra have become predominant.
• Hence this arcuate (curved) plain is also known as Indo-Gangetic-Brahmaputra Plain.

Features of Indo – Gangetic – Brahmaputra Plain

• Indo-Gangetic-Brahmaputra Plain is the largest alluvial tract of the world.
• It stretches for about 3,200 km from the mouth of the Indus to the mouth of the Ganga. Indian sector of the plain accounts for 2,400 km.
• The northern boundary is well marked by the Shiwaliks and the southern boundary is a wavy irregular line along the northern edge of the Peninsular India.
• The western boarder is marked by Sulaiman and Kirthar ranges. On the eastern side, the plains are bordered by Purvanchal hills.
• The width of the plain varies from region to region. It is widest in the west where it stretches for about 500 km. Its width decreases in the east.
• The thickness of the alluvium deposits also vary from place to place. The maximum depth of the alluvium up to the basement rocks is about 6,100 m (not uniform and varies greatly from place to place).
• The cones or alluvial fans of Kosi in the north and those of Son in the south exhibit greater alluvial thickness while the intra-cone areas have relatively shallower deposits.
• Extreme horizontality of this monotonous plain is its chief characteristic.
• Its average elevation is about 200 m above mean sea level, highest elevation being 291 m above mean sea level near Ambala (This elevation forms the drainage divide or watershed between Indus system and Ganga system).
• Its average gradient from Saharanpur to Kolkata is only 20 cm per km and it decreases to 15 cm per km from Varanasi to the Ganga delta.

Geomorphological features of Indo – Gangetic – Brahmaputra Plain

The Bhabar

• It is a narrow, porous, northern most stretch of Indo-Gangetic plain.
• It is about 8-16 km wide running in east-west direction along the foothills (alluvial fans) of the Shiwaliks.
• They show a remarkable continuity from the Indus to the Tista.
• Rivers descending from the Himalayas deposit their load along the foothills in the form of alluvial fans.
• These alluvial fans have merged together to build up the bhabar belt.
• The porosity of bhabar is the most unique feature.
• The porosity is due to deposition of huge number of pebbles and rock debris across the alluvial fans.
• The streams disappear once they reach the bhabar region because of this porosity.
• Therefore, the area is marked by dry river courses except in the rainy season.
• The Bhabar belt is comparatively narrow in the east and extensive in the western and north-western hilly region.

The area is not suitable for agriculture and only big trees with large roots thrive in this belt.

The Terai

• Terai is an ill-drained, damp (marshy) and thickly forested narrow tract to the south of Bhabar running parallel to it.
• The Terai is about15-30 km wide.
• The underground streams of the Bhabar belt re-emerge in this belt.

This thickly forested region provides shelter to a variety of wild life. [Jim Corbett National Park in Uttarakhand and Kaziranga National Park in Assam lie in terai region]

• The Terai is more marked in the eastern part than in the west because the eastern parts receive comparatively higher amount of rainfall.
• Most of the Terai land, especially in Punjab, Uttar Pradesh and Uttarakhand, has been turned into agricultural land which gives good crops of sugarcane, rice and wheat.

The Bhangar

• The Bhangar is the older alluvium along the river beds forming terraces higher than the flood plain.
• The terraces are often impregnated with calcareous concretions known as ‘KANKAR’.
• ‘The Barind plains’ in the deltaic region of Bengal and the ‘bhur formations’ in the middle Ganga and Yamuna doab are regional variations of Bhangar.

[Bhur denotes an elevated piece of land situated along the banks of the Ganga river especially in the upper Ganga-Yamuna Doab. This has been formed due to accumulation of wind-blown sands during the hot dry months of the year]

• Bhangar contains fossils of animals like rhinoceros, hippopotamus, elephants, etc.

The Khadar

• The Khadar is composed of newer alluvium and forms the flood plains along the river banks.
• A new layer of alluvium is deposited by river flood almost every year.
• This makes them the most fertile soils of Ganges.

Reh or Kollar

• Reh or Kollar comprises saline efflorescences of drier areas in Haryana.
• Reh areas have spread in recent times with increase in irrigation (capillary action brings salts to the surface)
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