Geography of India


is situated north of the equator between 8°4' north to 37°6' north latitude and 68°7' east to 97°25' east longitude. It is the seventh-largest country in the world, with a total area of. India measures from north to south and from east to west. It has a land frontier of and a coastline of.
On the south, India projects into and is bounded by the Indian Ocean—in particular, by the Arabian Sea on the west, the Lakshadweep Sea to the southwest, the Bay of Bengal on the east, and the Indian Ocean proper to the south. The Palk Strait and Gulf of Mannar separate India from Sri Lanka to its immediate southeast, and the Maldives are some to the south of India's Lakshadweep Islands across the Eight Degree Channel. India's Andaman and Nicobar Islands, some southeast of the mainland, share maritime borders with Myanmar, Thailand and Indonesia. The southernmost tip of the Indian mainland is just south of Kanyakumari, while the southernmost point in India is Indira Point on Great Nicobar Island. The northernmost point which is under Indian administration is Indira Col, Siachen Glacier. India's territorial waters extend into the sea to a distance of from the coast baseline. India has the 18th largest Exclusive Economic Zone of.
The northern frontiers of India are defined largely by the Himalayan mountain range, where the country borders China, Bhutan, and Nepal. Its western border with Pakistan lies in the Karakoram and Western Himalayan ranges, Punjab Plains, the Thar Desert and the Rann of Kutch salt marshes. In the far northeast, the Chin Hills and Kachin Hills, deeply forested mountainous regions, separate India from Myanmar. On the east, its border with Bangladesh is largely defined by the Khasi Hills and Mizo Hills, and the watershed region of the Indo-Gangetic Plain.
The Ganges is the longest river originating in India. The Ganges–Brahmaputra system occupies most of northern, central, and eastern India, while the Deccan Plateau occupies most of southern India. Kangchenjunga, in the Indian state of Sikkim, is the highest point in India at and the world's third highest peak. The climate across India ranges from equatorial in the far south, to alpine and tundra in the upper regions of the Himalayas. Geologically, India lies on the Indian Plate, the northern part of the Indo-Australian Plate.

Geological development

India is situated entirely on the Indian Plate, a major tectonic plate that was formed when it split off from the ancient continent Gondwanaland. The Indo-Australian plate 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, having moved faster than any other known plate. In 2007, German geologists determined that the Indian Plate was able to move so quickly because it is only half as thick as the other plates which 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 Plate is moving northeast at 5 cm/yr, while the Eurasian Plate is moving north at only 2 cm/yr. India is thus referred to as the "fastest continent". This is causing the Eurasian Plate to deform, and the Indian Plate to compress at a rate of 4 cm/yr.

Political geography

India is divided into 28 States and 8 union territories including the National capital territory.
India's borders run a total length of.
Its borders with Pakistan and Bangladesh were delineated according to the Radcliffe Line, which was created in 1947 during Partition of India. Its western border with Pakistan extends up to, dividing the Punjab region and running along the boundaries of the Thar Desert and the Rann of Kutch. This border runs along the Indian states and union territories of Ladakh, Jammu and Kashmir, Punjab, Rajasthan, and Gujarat. Both nations delineated a Line of Control to serve as the informal boundary between the Indian and Pakistan-administered areas of the Kashmir region. India claims the whole of the former princely state of Jammu and Kashmir, which includes areas now administered by Pakistan and China, which according to India are illegally occupied areas.
India's border with Bangladesh runs. West Bengal, Assam, Meghalaya, Tripura and Mizoram are the states which share the border with Bangladesh. Before 2015, there were 92 enclaves of Bangladesh on Indian soil and 106 enclaves of India were on Bangladeshi soil. These enclaves were eventually exchanged in order to simplify the border. After the exchange, India lost roughly to Bangladesh.
The Line of Actual Control is the effective border between India and the People's Republic of China. It traverses 4,057 km along the Indian states and union territories of Ladakh, Himachal Pradesh, Uttarakhand, Sikkim and Arunachal Pradesh. The border with Burma extends up to along the eastern borders of India's northeastern states viz. Arunachal Pradesh, Nagaland, Manipur and Mizoram. Located amidst the Himalayan range, India's border with Bhutan runs. Sikkim, West Bengal, Assam and Arunachal Pradesh are the states which share the border with Bhutan. The border with Nepal runs along the foothills of the Himalayas in northern India. Uttarakhand, Uttar Pradesh, Bihar, West Bengal and Sikkim are the states which share the border with Nepal. The Siliguri Corridor, narrowed sharply by the borders of Bhutan, Nepal and Bangladesh, connects peninsular India with the northeastern states.

Physiographic regions

Regions

India can be divided into six physiographic regions. They are:
An arc of mountains consisting of the Himalayas, Hindu Kush, and Patkai ranges define the northern frontiers of the Indian subcontinent. These were formed by the ongoing tectonic plates collision of the Indian and Eurasian plates. The mountains in these ranges include some of the world's tallest mountains which act as a barrier to cold polar winds. They also facilitate the monsoon winds which in turn influence the climate in India. Rivers originating in these mountains flow through the fertile Indo–Gangetic Plain. These mountains form the boundary between two biogeographic realms: the temperate Palearctic realm that covers most of Eurasia, and the tropical and subtropical Indomalayan realm which includes South Asia, Southeast Asia and Indonesia.
The Himalayas in India extend from Ladakh in the north to the state of Arunachal Pradesh in the east. Several Himalayan peaks in India rise above, including Kanchenjunga on the Sikkim–Nepal border, and Nanda Devi in the Garhwal Himalayas of Uttarakhand. The snow line ranges between in Sikkim to around in Ladakh. The Himalayas act as a barrier to the frigid katabatic winds flowing down from Central Asia. Thus, northern India is kept warm or only mildly cooled during winter; in summer, the same phenomenon makes India relatively hot.
  • The Karakoram range runs through Ladakh. The range is about in length and the most heavily glaciated part of the world outside of the polar regions. The Siachen Glacier at ranks as the world's second longest glacier outside the polar regions. The southern boundary of the Karakoram is formed by the Indus and Shyok rivers, which separate the range from the northwestern end of the Himalayas.
  • The Patkai, or Purvanchal, are situated near India's eastern border with Burma. They were created by the same tectonic processes which led to the formation of the Himalayas. The physical features of the Patkai mountains are conical peaks, steep slopes and deep valleys. The Patkai ranges are not as rugged or tall as the Himalayas. There are three hill ranges that 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.
Image:Manduvalley1 coolspark.jpg|thumb|right|The Vindhyas in central India

The Peninsular Plateau

This is a large region of the Indian subcontinent located between the Western Ghats and the Eastern Ghats, and is loosely defined as the peninsular region between these ranges that is south of the Narmada River.Having once constituted a segment of the ancient continent of Gondwanaland, this land is the oldest and most stable in India.
  • Mountain ranges
  • * Aravali Range is the oldest mountain range in India, running across Rajasthan from northeast to southwest direction, extending approximately. The northern 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, lying near the border with Gujarat. The Aravali Range is the eroded stub of an ancient fold mountain system. The range rose in a Precambrian event called the Aravali–Delhi orogen. The range joins two of the ancient segments that make up the Indian craton, the Marwar segment to the northwest of the range, and the Bundelkhand segment to the southeast.
  • * Vindhya range, lies north of Satpura range and east of Aravali range, runs across most of central India, extending. The average elevation of these hills is from and rarely goes above. They are believed to have been formed by the wastes created by the weathering of the ancient Aravali mountains. Geographically, it separates Northern India from Southern 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.
  • *Satpura Range, lies south of Vindhya range and east of Aravali range, begins in eastern Gujarat near the Arabian Sea coast and runs east across Maharashtra, Madhya Pradesh and Chhattisgarh. It extends with many peaks rising above. It is triangular in shape, with its apex at Ratnapuri and the two sides being parallel to the Tapti and Narmada rivers. It runs parallel to the Vindhya Range, which lies to the north, and these two east–west ranges divide the Indo–Gangetic plain from the Deccan Plateau located north of River Narmada.
  • Plateaus
  • *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.
  • * Chhota Nagpur Plateau is situated in eastern India, covering much of Jharkhand and adjacent parts of Odisha, Bihar and Chhattisgarh. Its total area is approximately and is made up of three smaller plateaus—the Ranchi, Hazaribagh, and Kodarma plateaus. The Ranchi plateau is the largest, with an average elevation of. Much of the plateau is forested, covered by the Chhota Nagpur dry deciduous forests. Vast reserves of metal ores and coal have been found in the Chota Nagpur plateau.
  • * Southern Garanulite terrain: Covers South India especially Tamil Nadu excluding western and eastern ghats. The Southern Granulite Terrain is one of the most geologically significant regions of the Indian Shield. It represents the southernmost part of the Indian peninsula, situated south of the stable Dharwar Craton.Unlike the lower-grade metamorphic rocks found further north, the SGT is composed of high-grade metamorphic rocks that were formed deep within the Earth's crust under extreme pressure and temperature.
  • ** Northern Boundary: It is separated from the Dharwar Craton by a transition zone often referred to as the "Fermor Line."
  • ** Major Shear Zones: These act as the "boundaries" between different blocks within the SGT:
  • *** Moyar-Bhavani Shear Zone: Separates the Dharwar Craton from the Nilgiri Block.
  • *** Palghat-Cauvery Shear Zone : A massive tectonic boundary that many geologists consider the "suture" where different ancient landmasses joined.
  • *** Achankovil Shear Zone : Located further south, separating the Madurai Block from the Trivandrum Block.
  • * Deccan Plateau, also called Deccan Trapps, is a large triangular plateau, bounded by the Vindhyas to the north and flanked by the Eastern and Western Ghats. The Deccan covers a total area of. It is mostly flat, with elevations ranging from. The average elevation of the plateau is above sea level. The surface slopes from in the west to in the east. 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 Ghats. Much of the Deccan is covered by thorn scrub forest scattered with small regions of deciduous broadleaf forest. Climate in the Deccan ranges from hot summers to mild winters.
  • * Kutch Kathiawar plateau is located in Gujarat state. The Kathiawar peninsula in western Gujarat is bounded by the Gulf of Kutch and the Gulf of Khambat. The natural vegetation in most of the peninsula is xeric scrub, part of the Northwestern thorn scrub forests ecoregion.