CH-2 | Geological Formations of India

1	Archean	First formed oldest rocks of the earth’s crust. No marks of fossils, i.e., they are azoic or unfossiliferous.	Gneiss, granite	Tamil Nadu, AP, Karnataka, Orissa, MP, Chattisgarh, Rajasthan, Jharkhand Also found in some parts of Himalayas.
2	Dharwar	Earliest formed sedimentary rocks that are found in metamorphic forms at present. Do not contain fossils. Highly metalliferous and the rocks carry iron-ore, gold, manganese, lead, zinc, building material etc.	Schist, slate, quartzite, conglomerates	Karnataka, MP, Jharkhand, Meghalaya, Rajasthan Also found in northern and central Himalayas.
3	Cuddapah	Rich in iron-ore, manganese ore	Slate, marble	Rajasthan, Tamil Nadu, AP, MP, Chattisgarh
4	Vindhyan	Generally stand over the cuddapah rocks.	Limestone, sandstone, shale, slate which are used as building materials	MP, Chattisgarh, UP, Rajasthan
5	Dravidian	Absent from the peninsular plateau as it was above the sea level at that time. Found in continuous sequence with the Himalayas.
6	Gondwana	Formed when the Indian peninsula experienced crustal movements during the Upper Carboniferous period, which led to the formation of basin-shaped depressions having countless terrestrial plants and animals that were buried to form coal deposits in India. Marks of climatic changes.		Damodar, Mahanadi, Godavari valley in peninsular India
7	Palaeozoic	Northern part of the central Himalayan axis extending from Kashmir to Sikkim		Gujarat, Rajasthan, Tamil Nadu, northern India
8	Mesozoic	Deccan traps were formed when vast areas of the peninsula were flooded with lava due to intense volcanic activity at the end of the Mesozoic era. Contain thin fossiliferous sedimentary layers between the lava flows which indicate that the lava flow was not continuous. The volcanic activity led to two great events – 1)       Breaking of Gondwana landmass 2)       Uplifting of the Himalayas out of Tethys Sea.
9	Tertiary	Comparatively recent origin.	Brown coal, rock salt, gypsum, limestone	Coastal areas of Gujarat, Kerala, Tamil Nadu.
10	Quaternary	Most recent Important formations are – 1)       Ice Age deposits in Kashmir 2)       Formation of alluvial plains 3)       Creation of Rajasthan desert & Rann of Kutch 4)       Laterite formation of peninsula 5)       Formation of regur soils.

CH-1 | Locational Setting of India

Comparison with china and Australia

Country	Area (km2)	Global Position	Latitudinal extent	Longitudinal extent	Water Bodies	North-South extension (km)	East-West extension (km)	Other Features
India	32,87,263 (2.4%)	7th	8°4’ N – 37°6’ N (30°)	68°7’ E – 97°25’ E (30°)	East – Bay of Bengal West – Arabian Sea South – Indian Ocean	3214	2933	Divided into half by Tropic of Cancer (23°50’ N)
Australia	76,86,848	6th	10°S – 44°S (34°)	114°E – 154°E (40°)	North-east & South – Indian Ocean West – South Pacific ocean	3219	4023	Divided into half by Tropic of Capricorn (23°50’ S)
	2.3 times		Roughly same	30% more
China	95.97 lakhs	3rd	18°N – 54°N (36°)	74°E – 135°E (61°)	East – Pacific ocean
	3 times		Roughly same	More than double

Importance of the Indian Ocean

1.       India lies at the apex of the arc formed by the Indian Ocean and thus has a commanding position.

2.       It has the largest coast-line in the Indian Ocean among the littoral countries and therefore has the maximum number of ports.

3.       The Deccan Peninsula projects into the Indian Ocean. India has access to the west and east, Indian ports get entrepot character.

4.       India has the greatest latitudinal extent among the littoral countries. Hence, it is diversified with climate and agricultural diversity.

5.       Most of the air, sea routes between Europe, West Asia, and Africa in the west; and East Asia, South East Asia, Japan and Australia, in the east pass through India.

India as a subcontinent

A landmass is named a subcontinent if it is geographically and politically distanced from the rest of the continent.  India is separated from the rest of Asia by the chain of lofty mountains, Himalayas, in the north; Indian Ocean in the south; Arabian Sea in the west; and Bay of Bengal in the east. Owing to the varied relief, India experiences topical monsoon climate, giving it a distinctive climatic pattern as compared to its neighbours. Hence, due to the vastness and diversity in culture and relief, India is considered a subcontinent.