INDIA & PHYSIOGRAPHY:
- Durand Line: Pakistan and Afghanistan
- Mac Mohan Line: India and China
- Radcliff Line: India and Pakistan
The physical features of India can be grouped under the following physiographic divisions
(i) The Himalayan Mountains
(ii) The Northern Plains
(iii) The Peninsular Plateau
(iv) The Indian Desert
(v) The Coastal Plains
(vi) The Islands
The Himalayan Mountains:
These mountain systems are one of the youngest of Fold Mountains in the world, characterised by its youthfulness, tectonic origin, great erosive capacity. Northern mountain consists of Himalayan ranges and trans himalaya which lies north of the great Himalayas. Karakoram , ladak and zaskar ranges are the part of trans Himalayas. Mt. K2 (Godwin Austin) the highest mountain in India is situated on the karakoram range. These ranges converge on the Palmir plateau.
- Aravallis are relict mountains lie to the north west of the peninsula. These are highly eroded and deeply worn down. Mt. Abu is an important peak of Aravallis.
- Bundelkhand lies in the east of Aravallis, formed by the erosion of gneisses and quartizites which offers the natural sites for water storage.
- Malwa is drained by chambal and betwa
- Vindhyan Kaimur range is a escarpment between Narmada and son valleys.
- Chhotanagpur plateau is the mineral rich area in India in the east of the son river
- Shillong Plateau is the continuation of the Deccan Plateau
- Deccan plateau is an elevated tableland consisting of horizontal lava beds and has a homogeneous sloping towards east and south east.
- Karnataka Plateau composed of gneisses and schists and the two main sub divisions are Malnad and Maidan.
- Western Ghats: It is also known as sahyadris stretch continuously to the southern tip have a general altitude 900-1100 kms. Dodabetta (2637m) is the highest peak inthe Nillagiri range. Anaimudi (2695 m) in annamalai is the highest peak in South India.
- Eastern Ghats are broken hills with no well defined structure. The eatern ghat are called northern hills in the northern sector , cudappah ranges in the middle sector and Tamil nadu hills in the southern sector.
The Indian Desert:
The Indian desest lies towards the western margins of the Aravali Hills. It is an undulating sandy plain covered with sand dunes. This region receives very low rainfall below 150 mm per year. It has arid climate with low vegetatin cover. Streams appear during the rainy season. Soon after they disappear into the sand as they do not have enough water to reach the sea. Luni is the only large river in this region. Barchans (crescent shaped dunes) cover larger areas but longitudinal dunes become more promiment near the Indo-Pakistan boundary. If you visit Jaisalmer, you may go to see a group of barchans.
This is the region between the coast and mountain ranges of the peninsular plateau. This can be divided into western and eastern coast. With the exception of Gujarat, the western coast is narrower than the eastern coast. It has characteristic lagoons or backwaters called kayals such as Asthamudi and vemband in the southern most stretch. The eastern coast has developed deltas of major rivers following through it.
India has 247 islands of which 204 lie in the Bay of Bengal and the remaining in the Arabian sea and gulf of mannar. The Andamans and the Nicobars form two major groups in Bay of Bengal Group. These 2 major groups are separated by Ten degree channel which 121 km wide. This chain of islands are formed by the submergence of Arakan Yoma ranges . The Barren and Narcondam islands , situated north of Port Blair , are volcanic islands. Lakshadweep islands are a group 27 of coral origin and are surrounded by fringing reefs with a total area of only 32 square kilometers. The pamban island , situated between India and Sri Lanka , has a rocky surface, is an extension of the peninisular surface in Ramnad district of Tamil Nadu.
INDIAN VULCANICITY: At present no active volcanoes except on the Barren Island (A/N Islands).