Physical geography of India

The Indian sub continent is situated to the North of the equator between 8°4' and 37°6' North latitude and 68°7' and 97°25' East longitude. It is the seventh-largest country in the world with a total area of 3,166,414 square kilometers. India measures up to 3,214 km from North to South and 2,933 km (1,822 mi) from East to West. It has a land frontier of 15,200 km and a coastline of 7,517 km.

India is a peninsula that is covered by the Indian Ocean and the Arabian Sea in the SouthWest, the Laccadive Sea in the South, the Bay of Bengal in the SouthEast and the Himalayan mountain range in the North-Eastern side. India also has major perennial rivers of the world- Ganga, Yamuna, Brahmaputra, Godavari and Krishna.

Geological formation:

India is entirely contained on the Indian Plate, a major tectonic plate that was formed after the split from the ancient continent Gondwanaland (ancient landmass, consisting of the Southern part of the supercontinent of Pangea). The Indo-Australian region is subdivided into the Indian and Australian plates. About 90 million years ago, during the late Cretaceous period, the Indian Plate began moving North at about 15 cm/year.

About 50 to 55 million years ago, in the Eocene Epoch of the Cenozoic Era, the plate collided with Asia after covering a distance of 2,000 to 3,000 km (1,243 to 1,864 mi), having moved faster than any other known plate. In 2007, German geologists determined that the Indian Plate was able to move with the said speed because it was half as thick as the other plates that formerly constituted Gondwanaland.

The collision with the Eurasian Plate along the modern border between India and Nepal formed the orogenic belt that created the Tibetan Plateau and the Himalayas. The Indian subcontinent has different physiographic regions that can majorly be divided into five regions - The Northen Mountains, Indo Gangetic Plains, The Peninsular Plateau, Thar Desert and The Coastal Plains.

The Northen Mountains

The Northen region of India is covered by the Himalayas, the Hindukush and the Purvanchal ranges. These were formed by the ongoing tectonic collision of the Indian and Eurasian plates. The mountains in these ranges include some of the world's tallest mountains that act as a natural barrier to cold polar winds. They also facilitate the monsoon winds that in turn influence the climate in India.

India has eight major mountain ranges with peaks of over 1,000 meters. The Himalayan range is considered to be the world's highest mountain range, with its tallest peak Mt. Everest (8,854 meters) situated on the Nepal–China border. They form India's NorthEastern border, separating it from NorthEastern Asia. Kanchenjunga—on the Sikkim–Nepal border—is the highest point in the area administered by India.

The Karakoram is situated in the Jammu and Kashmir. It has more than sixty peaks above 7,000 m, including K2, the second highest peak in the world at 8,611 m. K2 is just 237 m shorter than the Mount Everest. The Purvanchal is situated near India's Eastern border with Burma. It was created by the same tectonic processes that led to the formation of the Himalayas. The physical features of the Purvanchal Mountains are conical peaks, steep slopes and deep valleys.

Three hill ranges come under the Patkai: the Patkai–Bum, the Garo–Khasi–Jaintia and the Lushai hills. The Garo–Khasi range lies in Meghalaya. Mawsynram, a village near Cherrapunji lying on the windward side of these hills, has the distinction of being the wettest place in the world, receiving the highest annual rainfall.

The Vindhya Range runs across most of central India, extending to 1,050 km. The average elevation of these hills ranges from 300 to 600 m and rarely goes above 700 m. They are believed to have been formed by the wastes created by the weathering of the ancient Aravali mountains, which separate North India from the South India.

The Western end of the range lies in Eastern Gujarat, near its border with Madhya Pradesh, and runs East and North, almost meeting the Ganges at Mirzapur. The Satpura Range begins in Eastern Gujarat near the Arabian Sea coast and runs East across Maharashtra, Madhya Pradesh and Chhattisgarh. It extends as far as 900 km with many peaks rising above 1,000 m.

The Aravali Range is the oldest mountain range in India, running across Rajasthan from the NorthEast to the SouthWest direction, extending approximately 800 km. The Northen end of the range continues as isolated hills and rocky ridges into Haryana, ending near Delhi. The highest peak in this range is Guru Shikhar at Mount Abu, rising to 1,722 m (5,650 ft), lying near the border of Gujarat.

The Western Ghats or Sahyadri mountains run along the Western edge of India's Deccan Plateau and separate it from a narrow coastal plain along the Arabian Sea. The range runs approximately 1,600 km from the South of the Tapti River near the Gujarat–Maharashtra border and across Maharashtra, Goa, Karnataka, Kerala and Tamil Nadu to the Southern tip of the Deccan peninsula. The average elevation is around 1,000 m. Anai Mudi in the Anaimalai Hills at 2,695 m in Kerala is the highest peak in the Western Ghats.

The Eastern Ghats are discontinuous and have been eroded and vivisected by the four major rivers of Southern India, the Godavari, Mahanadi, Krishna, and Kaveri. These mountains extend from West Bengal to Orissa, Andhra Pradesh and Tamil Nadu, along the coast and parallel to the Bay of Bengal. The Nilgiri hills in Tamil Nadu lie at the junction of the Eastern and Western Ghats. Arma Konda (1,680 m in Andhra Pradesh is the tallest peak in Eastern Ghats.

Indo-Gangetic plain

It is considered as the most fertile area in India, as they are dominated by three main rivers, the Indus, Ganges, and Brahmaputra. They run parallel to the Himalayas, from Jammu and Kashmir in the West to Assam in the East, and drain most of Northern and Eastern India. The plains encompass an area of 700,000 km. The major rivers in this region are the Ganges, Indus, and Brahmaputra along with their main tributaries. The Indo- Gangetic plain can broadly be divided into four types- Bhabar, Terai, Bangar and Khadar.

Thar Desert

The Thar Desert is the seventh largest desert in the world. It forms a significant portion of Western India and covers an area of 200,000 to 238,700 km2. The desert continues into Pakistan as the Cholistan Desert. Most of the Thar Desert is situated in Rajasthan, covering 61 per cent of its geographic area. The only river in this region is Luni.

Highlands

The Central Highlands consists of three main plateaus the Malwa Plateau in the West, the Deccan Plateau in the South (covering most of the Indian peninsula) and the Chota Nagpur Plateau in the East. The Malwa Plateau is spread across Rajasthan, Madhya Pradesh and Gujarat. The average elevation of the Malwa plateau is 500 metres, and the landscape generally slopes towards the North. Most of the region is drained by the Chambal river and its tributaries; the Western part is drained by the upper reaches of the Mahi River.

The Deccan Plateau is a large triangular plateau, bounded by the Vindhyas in the North and flanked by the Eastern and Western Ghats. The Deccan covers a total area of 1.9 million square km. It slopes gently from West to East and gives rise to several peninsular rivers such as the Godavari, the Krishna, the Kaveri and the Mahanadi which drain into the Bay of Bengal. This region is mostly semi-arid as it lies on the leeward side of both the ghats.

The Chota Nagpur Plateau is situated in Eastern India, covering much of Jharkhand and adjacent parts of Orissa, Bihar and Chhattisgarh. Its total area is approximately 65,000 square km and is made up of three smaller plateaus — the Ranchi, the Hazaribagh, and the Kodarma plateaus.

Coastal Areas

The Eastern Coastal Plain is a wide stretch of land lying between the Eastern Ghats and the Bay of Bengal. It stretches from Tamil Nadu in the South to West Bengal in the East. The plains are divided into six regions—the Mahanadi delta, the Southern Andhra Pradesh plain, the Krishna-Godavari deltas, the Kanyakumari coast, the Coromandel Coast, and sandy coastal.

The Western Coastal Plain is a narrow strip of land sandwiched between the Western Ghats and the Arabian Sea, ranging from 50 to 100 km in width. It extends from Gujarat in the North and extends through Maharashtra, Goa, Karnataka, and Kerala. The Western coastal plain can be divided into two parts, the Konkan and the Malabar Coast.

Islands

The Lakshadweep and the Andaman and Nicobar Islands are India's two major island formations and are classified as union territories. The Lakshadweep Islands lie 200 to 300 km off the coast of Kerala in the Arabian Sea with an area of 32 square km. The Andaman and Nicobar Islands are located between 6° and 14° North latitude and 92° and 94° East longitude.

Other significant islands in India include Daman & Diu, a former Portuguese enclave; Majuli, a river island of the Brahmaputra; Elephanta in Bombay Harbour; and Sriharikota, a barrier island in Andhra Pradesh. Salsette Island is India's most populous island on which the city of Mumbai (Bombay) is located. Forty-two islands in the Gulf of Kutch constitute the Marine National Park.