The Western Ghats and Eastern Ghats

 In this article You will read Western Ghats and Eastern Ghats for UPSC IAS Exam.

The Western Ghats and Eastern Ghats

The Deccan plateau of India is one of the main landmasses and is studied as one of India’s physiographic divisions. It is bordered by the Western Ghats on its west and the Eastern Ghats on its east. The Western Ghats are continuous mountain ranges called Sahyadri; While the Eastern Ghats are discontinuous mountain ranges.

Western Ghats (or The Sahyadris)

The Western Ghats have been formed by the subduction of the Arabian basin and tilting of the peninsula in east and northeast during Himalayan uplift. Thus, it wears the look of block mountains in the west and the slope appears to be escarpments and stairway formation.

Thus along the west coast, they look like Treppen.

The eastern section, however, is a rolling plateau with an extremely low slope and gradually merges with the sudden plateau.

The Western Ghats is one of the eight hotspots of biological diversity in the world and is spread across six states—Gujarat, Maharashtra, Goa, Karnataka, Tamil Nadu and Kerala.

It is a UNESCO World Heritage site. It is one of the eight “hottest hot-spots” of biological diversity in the world. According to UNESCO, the Western Ghats are older than the Himalayas. They influence Indian monsoon weather patterns by intercepting the rain-laden monsoon winds that sweep in from the south-west during late summer.

• 

  block mountains

• 

  block mountains – Treppen

• It stretches from Tapi valley to Kanyakumari.
• It is called Sahyadri till 11° N.
• It has three sections.
  • Northern Western Ghats
  • Middle Sahyadri(Central Western Ghats)
  • Southern Western Ghats

Northern Western Ghats

• Northern Western Ghats – located B/N Tapi valley and 16° N lat. It has a basaltic lava cover. The highest point is Kalsubai. Highly rugged and dissected by rivers.
• The northern section of the Ghats from Tapi valley to a little north of Goa is made of horizontal sheets of Deccan lavas (Deccan Traps).
• The average height of this section of the Ghats is 1,200 m above mean sea level, but some peaks attain more heights.
• Kalasubai (1,646 m), Salher (1,567 m) about 90 km north of Nashik, Mahabaleshwar (1,438 m) and Harishchandragarh (1,424 m) are important peaks.
• Thal ghat and Bhor ghat are important passes that provide passage by road and rail between the Konkan Plains in the west and the Deccan Plateau in the east.

The Middle Sahyadri

• The Middle Sahyadri runs from 16°N latitude up to Nilgiri hills.
• This part is made of granites and gneisses.
• This area is covered with dense forests.
• The western scarp is considerably dissected by headward erosion of the west-flowing streams.
• The average height is 1200 m but many peaks exceed 1500 m.
• The Vavul Mala (2,339 m), the Kudremukh (1,892 m), and Pashpagiri (1,714 m) are important peaks.
• The Nilgiri Hills which join the Sahyadris near the trijunction of Karnataka, Kerala, and TN, rises abruptly to over 2,000 m.
• They mark the junction of the Western Ghats with the Eastern Ghats.
• Doda Betta (2,637 m) and Makurti (2,554 m) are important peaks of this area.
• Central Western Ghats (B/w 16° – 11° N)- It has a granitic structure. In Karnataka, the highest point is Mulangiri in Baba Budan Hill. This section has developed nick points, waterfalls like Gersoppa/jog Falls over Sharavathi River
• This section has two distinctive features – Malnad, are highlands and Maidan, plateau surface. River Kaveri emerges from Brahmagiri Hills – the lake is called Talkaveri Lake.

The Southern section

• The southern part of the Western Ghats is separated from the main Sahyadri range by Pal ghat Gap (Palakkad Gap).
• It is also called the southern mountain complex.
• The high ranges terminate abruptly on either side of this gap.
• Pal ghat Gap is a rift valley. This gap is used by a number of roads and railway lines to connect the plains of Tamil Nadu with the coastal plain of Kerala.
• It is through this gap that moist-bearing clouds of the southwest monsoon can penetrate some distance inland, bringing rain to the Mysore region.
• South of the Pal ghat Gap there is an intricate system of steep and rugged slopes on both the eastern and western sides of the Ghats.
• Anai Mudi (2,695 m) is the highest peak in the whole of southern India.
• Three ranges radiate in different directions from Anai Mudi. These ranges are the Anaimalai (1800-2000 m) to the north, the Palani (900-1,200 m) to the north-east, and the Cardamom Hills or the Ealaimalai to the south.

• Southern Western Ghats has 3 parallel ranges to the coast namely–
  • Nilgiris
  • Annamalai
  • Cardamon and
  • Transverse range – Palani
• Palghat gap is B/W the southern part of the Western Ghats and the main Sahyadri
• These mountains have an average elevation of 1600 – 2500m.
  • Dodabetta is the highest peak of Nilgiris
  • Anamudi is the highest peak of Annamalai and South India.
  • Agasti malai is the highest peak of Cardamom hills.

Eastern Ghats

• The Eastern Ghats run almost parallel to the east coast of India leaving broad plains between their base and the coast.
• It is a chain of highly broken and detached hills starting from the Mahanadi in Odisha to the Vagai in Tamil Nadu. They almost disappear between the Godavari and the Krishna.
• They neither have structural unity nor physiographic continuity. Therefore these hill groups are generally treated as independent units.
• It is only in the northern part, between the Mahanadi and the Godavari that the Eastern Ghats exhibit true mountain character. This part comprises the Maliya and the Madugula Konda ranges.
• The peaks and ridges of the Maliya range have a general elevation of 900-1,200 m and Mahendra Giri (1,501 m) is the tallest peak here.
• The Madugula Konda range has higher elevations ranging from 1,100 m and 1,400 m with several peaks exceeding 1,600 m. Jindhagada Peak (1690 m) in Araku Valley Arma Konda (1,680 m), Gali Konda (1,643 m), and Sinkram Gutta (1,620 m) are important peaks.
• Between the Godavari and the Krishna rivers, the Eastern Ghats lose their hilly character and are occupied by Gondwana formations (KG Basin is here).
• The Eastern Ghats reappear as more or less a continuous hill range in Cuddapah and Kurnool districts of Andhra Pradesh where they are called as Nallamalai Range {Naxalite hideout in AP} with a general elevation of 600-850 m.
• The southern part of this range is called the Palkodna range.
• To the south, the hills and plateaus attain very low altitudes; only Javadi Hills and the Shevroy-Kalrayan Hills form two distinct features of 1,000 m elevation.
• The Biligiri Rangan Hills in Karnataka (at its border with Tamil Nadu) attain a height of 1,279 m.
• Further south, the Eastern Ghats merge with the Western Ghats.

• Geologically they are Precambrian fold mountains and the younger contemporary to Aravalli.
• Presently they are highly dissected, fragmented and appear as hills of denudation running roughly along the eastern coast
• Average Elevation – 150-300m ( Very low)
• They are made of different rock systems.
• Khondelite series is the major rock system, found in the central part of AP, Orissa.
• Southern Part in TN has Granitic Gneiss.
• Peninsular rivers have carved out wide U shaped valleys. Thus, these mountains are scattered.
• In TN, they are called Shevaroy Hills, Javadi Hills.
• In AP, they are caled Palkonda range, Vellikonda range and Nalamallai hills
• It is called Northern Circars b/w Godavari and Mahanadi basin, which are the highest part of the Eastern Ghats.
• In Orissa, the highest point is Mahendragiri in Ganjam District.
• These mountains are hardly watershed, thus no rivers except R.Indravati emerge from the Eastern Ghats.

Difference between Western Ghats vs Eastern Ghats

Western Ghats	Eastern Ghats
600 – 1200m, still higher in South	150-300 m
Rock System – Chernochete	Gneiss, Khondalite, Dharwar
Due to tilting, further upliftment	Further subdued
The most important watershed in southern India – all east-flowing rivers emerging	Poor Watershed
Treppen – Like formation, look like block mountains in the west	Ancient fold mountains and presently mountains of denudation
DenselyForested	Less Forested – Mostly dry deciduous to moist deciduous
Laterite Soils found	Red Sandy soil
100cm isohyte is the crest of Western Ghats. It rains 150cm+ all along the west coast	Rainfall 60-100 cm

Significance of the Peninsular Plateau

• There are huge deposits of iron, manganese. copper, bauxite, chromium, mica, gold, etc.
• 98 percent of the Gondwana coal deposits of India are found in the Peninsular Plateau.
• Besides, there are large reserves of slate, shale, sandstones, marbles, etc.
• A large part of the northwest plateau is covered with fertile black lava soil which is extremely useful for growing cotton.
• Some hilly regions in south India are suitable for the cultivation of plantation crops like tea, coffee, rubber, etc..
• Some low-lying areas of the plateau are suitable for growing rice.
• The highlands of the plateau are covered with different types of forests that provide a large variety of forest products.
• The rivers originating in the Western Ghats offer great opportunities for developing hydroelectricity and providing irrigation facilities to the agricultural crops.
• The plateau is also known for its hill resorts such as Udagamangalam (Ooty), Panchmarhi, Kodaikanal, Mahabaleshwar, Khandala, Matheron, Mount Abu, etc.