Our Revision Notes for GSEB Class 9 Social Science Notes Chapter 14 India: Location,Geological Structure and Physiography 2 summarises the key points of a chapter and useful resource to prepare effectively for the upcoming board exams.
India: Location,Geological Structure and Physiography 2 Class 9 GSEB Notes Social Science Chapter 14
India: Location,Geological Structure and Physiography 2 Class 9 GSEB Notes
→ Himalayas as the whole can be divided into two divisions:
- Northern Himalayan Region
- Eastern Himalayas
Northern Himalayan region:
- The northern range is called the Greater Himalayas.
- This is the loftiest range among the Himalayas wherein there are more than 40 peaks which exceed height of 7000 metres.
- Most famous among them is Mt. Everest which is 8848 metres high.
- It is on Nepal – China border.
- Second Range is called Central Himalayas or the Lesser Himalayas. With a width ranging from 80 to 100 km.
- Includes mountain ranges like Pir Panjal, Mahabharata, Nagtiba etc.
- Many hill stations have developed in this moderately high range.
- Third range, situated in further south is known as Shivalik.
- It is about 10 to 15km wide and has an average height of 1000 metres.
- Eastern part of Himalayan ranges have lesser height. Some of them are more famous as Hills.
- Mountainous regions have more rainfall so dense forests have developed here.
Great Northern Plain:
- This northern plain is located between the northern mountainous region and the southern peninsula. This plain is formed due to the alluvial sediments brought by Himalayan rivers such as Satluj, Ganga and Brahmaputra.
- The plain is about 2400 km long. It is considered as one of the largest river plains of the world.
- Sindhu river and its tributaries Jhelum, Chenab, Ravi, Beas and Satluj originate in Himalayas. Generally, a region between two rivers is called ‘Doab’.
Peninsular Plateau can be divided into two parts
- Malwa Plateau
- Deccan Plateau.
- Aravalli Range is situated to the north-west part of Malwa plateau.
- Aravalli is one of the oldest ranges in the world. It is a folded mountain. Mt. Abu is the famous hill station on this range.
- The Deccan Plateau is situated to the south of Satpuda, Mahadev and Maikal ranges which are located to the south of the Malwa plateau.
- The average height of Deccan Plateau ranges between 900 to 1000 metres,
Coastal Plains (Plains along the sea coast):
- Peninsular plateau is divided into western and eastern coastal plains. The west coast plain is spread from Gujarat to Kerala.
- East coast plain is much broader than the west coast plain.
- Andaman and Nicobar and Lakshadweep are major archipelagos.
- Such coral islands are called ‘Atolls’.
- Northern fertile plains are also called storehouse of Grains. Southern plateau in rich in many mineral resources.
- Many rivers with large volume of water originate in the northern mountainous region which is also known for a variety of forest resources.
- A composite matter made up of one or more minerals is called a ‘Rock’. Rocks can be hard as well as soft.
- They can be porous or non-porous, and can be light or heavy in weight.
- Minerals are available from the interior of the earth in solid, liquid and gaseous forms.
- Coal, minerals oil and natural gas etc. are available from stratified rocks, while slate, marble, diamond etc. are available from metamorphic rocks.
Classification of minerals:
- Metallic minerals
- Non-Metallic minerals
- Energy resources:
Coal, mineral oil and natural gas, uranium, thorium etc.
- Soil is the result of denudation of rocks.
- Soils in India are classified into six types:
- Alluvial Soil: It can be divided into two parts:
(1) Khadar, and
→ Black Soil : This soil is found mostly in Maharashtra, western Madhya Pradesh, Gujarat, Karnataka, Andhra Pradesh, Telangana and Tamil Nadu. Black soil is the gift of peninsular plateau.
→ Red Soil: Such soil is found in regions of igneous of igneous rocks. Its red colour is due to its ferrous and other humus contents.
→ Laterite Soil: It develops as a result of excessive erosion by rain. Due to heavy rain, the humus contents from the top soil descent into the lower strata which is called leaching.
→ Mountain Soil: The soil is sandy and porous and does not contain humus. Such soil is found in the mountainous region of the country, such as in Meghalaya, Arunachal Pradesh, Eastern hill ranges, Uttarakhand, Himachal Pradesh and Jammu and Kashmir states.
→ Desert Soil: Such soil is found in the arid and semi-arid regions of Gujarat, Rajasthan, Punjab and Haryana. The soil here is more alkaline and has less humus contents.