- Understand the geological history of the Earth and its impact on landforms.
- Identify the three major geological divisions of India: the Peninsular Block, the Himalayas, and the Indo-Ganga-Brahmaputra Plain.
- Describe the characteristics of the Peninsular Block, including its ancient geological formations and major landforms.
- Explain the geological structure and features of the Himalayas and other Peninsular mountains.
- Analyze the formation and significance of the Indo-Ganga-Brahmaputra Plain.
- Discuss the physiographic divisions of India, including the Northern and North-eastern Mountains, the Northern Plain, the Peninsular Plateau, the Indian Desert, the Coastal Plains, and the Islands.
- Evaluate the impact of endogenic and exogenic forces on the physical environment of India.
- Compare the characteristics of the western and eastern coastal plains of India.
Structure and Physiography
CBSE Learning Objectives – Key Concepts & Skills You Must Know
CBSE Revision Notes & Quick Summary for Last-Minute Study
Structure and Physiography
Overview
- The earth is approximately 4600 million years old and has undergone changes due to endogenic and exogenic forces.
- The Indian plate was once larger and located south of the equator.
- The northward movement of the Indian plate continues to impact the physical environment of the Indian subcontinent.
Geological Divisions of India
India can be divided into three geological divisions based on geological structure:
- The Peninsular Block
- The Himalayas and other Peninsular Mountains
- Indo-Ganga-Brahmaputra Plain
The Peninsular Block
- Formed by ancient gneisses and granites.
- Stands as a rigid block with some areas affected by tectonic activity.
- Includes features like:
- Rift valleys: Narmada, Tapi, Mahanadi.
- Mountains: Aravali, Nallamala, Javadi, Veliconda, Palkonda, Mahendragiri.
The Himalayas and Other Peninsular Mountains
- Young and flexible geological structure.
- Subject to ongoing geological processes, resulting in:
- Landforms: Gorges, V-shaped valleys, rapids, waterfalls.
Indo-Ganga-Brahmaputra Plain
- Formed by the rivers Indus, Ganga, and Brahmaputra.
- Originally a geo-synclinal depression filled with sediments.
- Average depth of alluvial deposits: 1,000-2,000 m.
- Supports a variety of crops due to fertile alluvial soil.
Physiography of India
- Characterized by diverse physical features:
- Northern and North-eastern Mountains
- Northern Plain
- Peninsular Plateau
The Peninsular Plateau
- Irregular triangle with an elevation of 150 m to 900 m.
- Comprises:
- The Deccan Plateau
- The Central Highlands
- The Northeastern Plateau
The Deccan Plateau
- Bordered by Western and Eastern Ghats.
- Contains major rivers originating from the Western Ghats.
The Central Highlands
- Bounded by the Aravali range and characterized by relict mountains.
The Northeastern Plateau
- Extension of the main Peninsular plateau with rich mineral resources.
The Indian Desert
- Located northwest of the Aravali hills, characterized by low rainfall and arid climate.
- Known for features like longitudinal dunes and barchans.
Coastal Plains
- Divided into:
- Western Coastal Plains: Submerged coastal plain with natural ports.
- Eastern Coastal Plains: Emergent coast with well-developed deltas.
Islands
- Andaman and Nicobar Islands: Elevated portions of submarine mountains.
- Lakshadweep Islands: Built of coral deposits, scattered off the Kerala coast.
Conclusion
- India's geological structure significantly influences its physiography and relief, resulting in diverse landforms and ecosystems.
CBSE Exam Tips, Important Questions & Common Mistakes to Avoid
Common Mistakes and Exam Tips
Common Pitfalls
- Misunderstanding Geographical Terms: Students often confuse terms like 'delta' and 'plain'. Ensure you understand the definitions and characteristics of each.
- Ignoring the Importance of Scale: When interpreting maps, students may overlook the scale, leading to incorrect conclusions about distances and sizes.
- Overlooking Key Features: In questions about physical geography, students sometimes fail to mention significant features such as major rivers, mountains, or plains that are crucial for full marks.
Tips for Exam Preparation
- Review Key Concepts: Regularly revisit the definitions and characteristics of major geographical features, such as the Peninsular Block and the Indo-Ganga-Brahmaputra Plain.
- Practice Map Work: Familiarize yourself with maps of India, focusing on the locations of important landforms and water bodies.
- Answer Structure: When answering descriptive questions, structure your responses clearly, using subheadings if necessary to organize your thoughts.
- Time Management: Allocate time wisely during exams to ensure you can answer all questions, especially those requiring detailed explanations.
CBSE Quiz & Practice Test – MCQs, True/False Questions with Solutions
Multiple Choice Questions
A.
Rift valleys
B.
Volcanic mountains
C.
Block mountains
D.
Tors
Correct Answer: B
Solution:
The Peninsular Plateau is characterized by features such as rift valleys, block mountains, and tors. Volcanic mountains are not typically associated with this region.
A.
Godavari
B.
Krishna
C.
Ganga
D.
Kaveri
Correct Answer: C
Solution:
The Ganga river does not originate from the Western Ghats. It originates from the Himalayas. The Godavari, Krishna, and Kaveri rivers originate from the Western Ghats.
A.
Volcanic activity
B.
Tectonic uplift
C.
Alluvial deposits
D.
Glacial erosion
Correct Answer: C
Solution:
The Indo-Ganga-Brahmaputra Plain was formed by alluvial deposits brought by the rivers Indus, Ganga, and Brahmaputra.
A.
1,500 km
B.
2,500 km
C.
3,500 km
D.
4,500 km
Correct Answer: B
Solution:
The approximate length of the Great Himalayan range is 2,500 km from east to west.
A.
Ganga
B.
Narmada
C.
Yamuna
D.
Brahmaputra
Correct Answer: B
Solution:
The Narmada River is known for forming a rift valley in the Peninsular Plateau.
A.
Sedimentary rocks
B.
Volcanic rocks
C.
Ancient gneisses and granites
D.
Limestone and shale
Correct Answer: C
Solution:
The Peninsular Plateau is primarily composed of ancient gneisses and granites, making it one of the oldest and most stable landmasses in India.
A.
11° Channel
B.
10° Channel
C.
Andaman Sea
D.
Gulf of Mannar
Correct Answer: B
Solution:
The Andaman Islands are separated from the Nicobar Islands by the 10° Channel.
A.
Formation of the Himalayan mountain range
B.
Creation of the Great Indian Desert
C.
Emergence of the Western Ghats
D.
Submergence of the city of Dwaraka
Correct Answer: A
Solution:
The northward movement of the Indian plate led to the collision with the Eurasian plate, resulting in the upliftment of the Himalayan mountain range.
A.
The Northern Plains
B.
The Sahara Desert
C.
The Amazon Basin
D.
The Rocky Mountains
Correct Answer: A
Solution:
The Northern Plains are one of the major physiographic divisions of India, formed by the alluvial deposits of the Indus, Ganga, and Brahmaputra rivers.
A.
Formation of the Himalayas
B.
Frequent earthquakes in the Himalayan region
C.
Formation of coral reefs in the Andaman Sea
D.
Continued upliftment of the Tibetan Plateau
Correct Answer: C
Solution:
The formation of coral reefs in the Andaman Sea is not related to the northward movement of the Indian plate. This movement primarily affects the Himalayan region, leading to the formation of the Himalayas, earthquakes, and upliftment of the Tibetan Plateau.
A.
Ganga
B.
Luni
C.
Yamuna
D.
Brahmaputra
Correct Answer: B
Solution:
The Luni river is significant in the southern part of the Indian desert.
A.
The Peninsular Block
B.
The Himalayas
C.
Indo-Ganga-Brahmaputra Plain
D.
The Coastal Plains
Correct Answer: A
Solution:
The Peninsular Block consists of relict and residual mountains like the Aravali hills and the Nallamala hills.
A.
Sedimentary rocks
B.
Metamorphic rocks
C.
Igneous rocks
D.
Limestone
Correct Answer: B
Solution:
The Peninsular Plateau is primarily composed of metamorphic rocks such as gneiss and granite.
A.
High elevation
B.
Low rainfall
C.
Proximity to the sea
D.
Dense vegetation
Correct Answer: B
Solution:
The Indian Desert has an arid climate due to low rainfall, receiving below 150 mm per year.
A.
Presence of relict and residual mountains
B.
Formation of young fold mountains
C.
Presence of active volcanoes
D.
Formation of large deltas
Correct Answer: A
Solution:
The Peninsular Plateau is characterized by relict and residual mountains like the Aravali hills.
A.
Aravali Range
B.
Nilgiri Hills
C.
Anaimalai Hills
D.
Satpura Range
Correct Answer: C
Solution:
Anaimalai Hills are known for having 'Anaimudi', the highest peak in the Peninsular Plateau.
A.
Himalayas
B.
Aravali Range
C.
Western Ghats
D.
Eastern Ghats
Correct Answer: B
Solution:
The Aravali Range forms the northern boundary of the Peninsular Block.
A.
Rift valleys of the Narmada and Tapi
B.
Deltas of the Ganga and Brahmaputra
C.
Coral islands of Lakshadweep
D.
Sand dunes of the Thar Desert
Correct Answer: A
Solution:
The rift valleys of the Narmada and Tapi are formed due to the vertical movements and block faulting, which are endogenic forces acting on the Peninsular Block.
A.
The Northern Plains
B.
The Peninsular Plateau
C.
The Coastal Plains
D.
The Indian Desert
Correct Answer: D
Solution:
The Great Indian Desert is a distinct physiographic division known as the Indian Desert.
A.
Presence of black soil
B.
High mountain ranges
C.
Fertile alluvial soil
D.
Desert landscape
Correct Answer: C
Solution:
The Northern Plains are characterized by fertile alluvial soil, which supports a variety of crops.
A.
Volcanic activity
B.
Tectonic uplift
C.
Alluvial deposition
D.
Glacial erosion
Correct Answer: C
Solution:
The Indo-Ganga-Brahmaputra Plain was formed by the alluvial deposits brought by the rivers Indus, Ganga, and Brahmaputra.
A.
Nilgiri hills
B.
Anaimalai hills
C.
Cardamom hills
D.
Nallamala hills
Correct Answer: A
Solution:
The 'Dodabeta' peak is situated on the Nilgiri hills.
A.
The Northern Plains
B.
The Peninsular Plateau
C.
The Indian Desert
D.
The Coastal Plains
Correct Answer: A
Solution:
The Northern Plains are known for their fertile alluvial soil, supporting a variety of crops.
A.
Nilgiri hills
B.
Anaimalai hills
C.
Cardamom hills
D.
Nallamala hills
Correct Answer: B
Solution:
Anaimudi, the highest peak of the Peninsular plateau, is located on the Anaimalai hills.
A.
The Peninsular Block
B.
The Himalayas
C.
The Indo-Ganga-Brahmaputra Plain
D.
The Coastal Plains
Correct Answer: C
Solution:
The Indo-Ganga-Brahmaputra Plain is one of the primary geological divisions of India.
A.
Nilgiri hills
B.
Anaimalai hills
C.
Cardamom hills
D.
Nallamala hills
Correct Answer: A
Solution:
Dodabeta peak is situated on the Nilgiri hills.
A.
Ladakh
B.
Rajasthan
C.
Kerala
D.
Sundarbans
Correct Answer: A
Solution:
Ladakh is known for having a cold desert climate, characterized by low precipitation and high altitude.
A.
Himalayas
B.
Aravali Range
C.
Western Ghats
D.
Eastern Ghats
Correct Answer: B
Solution:
The northern boundary of the Peninsular Block is marked by the Aravali Range.
A.
The Peninsular Block
B.
The Himalayas
C.
Indo-Ganga-Brahmaputra Plain
D.
The Indian Desert
Correct Answer: A
Solution:
The Peninsular Block is formed essentially by a great complex of very ancient gneisses and granites.
A.
Narmada
B.
Tapi
C.
Mahanadi
D.
Luni
Correct Answer: C
Solution:
The Mahanadi river forms a delta before entering the Bay of Bengal.
A.
Block faulting
B.
Volcanic activity
C.
River erosion
D.
Glacial movement
Correct Answer: A
Solution:
The rift valleys of the Narmada, Tapi, and Mahanadi are formed due to block faulting, a process associated with tectonic activity in the Peninsular Block.
A.
4600 million years
B.
3600 million years
C.
5600 million years
D.
2600 million years
Correct Answer: A
Solution:
The Earth is approximately 4600 million years old as per current estimations.
A.
Aravali Range
B.
Western Ghats
C.
Himalayas
D.
Eastern Ghats
Correct Answer: C
Solution:
The Himalayas act as a climatic, drainage, and cultural divide in India, influencing the climate and river systems and acting as a barrier to cultural exchanges.
A.
The Northern Plains
B.
The Peninsular Plateau
C.
The Coastal Plains
D.
The Indian Desert
Correct Answer: B
Solution:
The Shillong and Karbi-Anglong plateau are part of the Peninsular Plateau.
A.
Ganga
B.
Narmada
C.
Yamuna
D.
Brahmaputra
Correct Answer: B
Solution:
The Narmada River flows through a rift valley, which is a characteristic feature of the Peninsular Block.
A.
Mahanadi
B.
Godavari
C.
Krishna
D.
Narmada
Correct Answer: D
Solution:
The Narmada River does not form a delta; instead, it flows through a rift valley and drains into the Arabian Sea.
A.
Narmada
B.
Tapi
C.
Godavari
D.
Luni
Correct Answer: C
Solution:
The Godavari river is known for forming a significant delta before entering the Bay of Bengal. The Narmada and Tapi do not form deltas as they flow westward into the Arabian Sea, and the Luni is an ephemeral river in the Thar Desert.
A.
Aravali Hills
B.
Himalayas
C.
Western Ghats
D.
Vindhyan Range
Correct Answer: B
Solution:
The Himalayas are young mountains that are still geologically active, experiencing exogenic and endogenic forces, leading to the formation of faults, folds, and thrust plains.
A.
River water
B.
Rainwater
C.
Brackish water from lakes and playas
D.
Groundwater
Correct Answer: C
Solution:
The main source of obtaining salt in the Indian desert is the brackish water from lakes and playas.
A.
Lakshadweep
B.
Andaman and Nicobar Islands
C.
Minicoy
D.
Ritchie's Archipelago
Correct Answer: B
Solution:
The Andaman and Nicobar Islands are known for having Barren Island, the only active volcano in India.
A.
Ancient gneisses and granites
B.
Young fold mountains
C.
Volcanic plateaus
D.
Coral islands
Correct Answer: A
Solution:
The Peninsular Block is primarily composed of ancient gneisses and granites, making it a stable geological region.
A.
High elevation
B.
Submerged coastal plain
C.
Lack of rivers
D.
Dense vegetation
Correct Answer: B
Solution:
The western coastal plains are submerged, which prevents the formation of deltas.
A.
Andaman and Nicobar Islands
B.
Lakshadweep and Minicoy
C.
Sri Lanka and India
D.
Maldives and Lakshadweep
Correct Answer: A
Solution:
The Ten Degree Channel separates the Andaman Islands from the Nicobar Islands in the Bay of Bengal.
A.
Volcanic activity
B.
Alluvial deposition
C.
Tectonic uplift
D.
Glacial erosion
Correct Answer: B
Solution:
The Indo-Ganga-Brahmaputra Plain is formed by the alluvial deposits brought by the rivers Indus, Ganga, and Brahmaputra.
A.
The Northern Plains
B.
The Peninsular Plateau
C.
The Himalayas
D.
The Coastal Plains
Correct Answer: C
Solution:
The Himalayas consist of a series of parallel mountain ranges and act as a significant climatic, drainage, and cultural divide in the Indian subcontinent.
A.
The Peninsular Block
B.
The Himalayas
C.
Indo-Ganga-Brahmaputra Plain
D.
The Coastal Plains
Correct Answer: A
Solution:
The Peninsular Block is characterized by its ancient gneisses and granites, making it a stable landmass.
A.
11° Channel
B.
Gulf of Mannar
C.
10° Channel
D.
Andaman Sea
Correct Answer: C
Solution:
The Andaman Islands are separated from the Nicobar Islands by the 10° Channel.
A.
Tectonic upliftment
B.
Volcanic activity
C.
Sediment deposition by rivers
D.
Wind erosion
Correct Answer: C
Solution:
The Indo-Ganga-Brahmaputra Plain was formed by the deposition of sediments brought by the rivers Indus, Ganga, and Brahmaputra. These alluvial deposits created the vast plains.
A.
High tidal activity
B.
Submergence of the coast
C.
High sedimentation rates
D.
Presence of coral reefs
Correct Answer: B
Solution:
The western coastal plains are narrow and have been submerged, which prevents the formation of extensive deltas. This submergence provides natural conditions for the development of ports and harbours instead.
A.
The Deccan Traps
B.
The Indo-Ganga-Brahmaputra Plain
C.
The Western Ghats
D.
The Eastern Ghats
Correct Answer: B
Solution:
The Indo-Ganga-Brahmaputra Plain is primarily formed by the sediment deposition from the Himalayan and Peninsular rivers, which is a result of both endogenic (tectonic uplift) and exogenic (erosion and sedimentation) forces.
A.
Ganga
B.
Narmada
C.
Yamuna
D.
Brahmaputra
Correct Answer: B
Solution:
The Narmada River forms a rift valley in the Peninsular Block, which is a characteristic feature of this region.
A.
11° Channel
B.
Gulf of Mannar
C.
10° Channel
D.
Andaman Sea
Correct Answer: C
Solution:
The Andaman Islands are separated from the Nicobar Islands by the 10° Channel.
A.
The Northern Plains
B.
The Peninsular Plateau
C.
The North and Northeastern Mountains
D.
The Coastal Plains
Correct Answer: C
Solution:
The North and Northeastern Mountains, which include the Himalayas, are characterized by rugged topography with a series of mountain ranges, peaks, valleys, and gorges.
A.
The Northern Plains
B.
The Peninsular Plateau
C.
The Coastal Plains
D.
The Islands
Correct Answer: B
Solution:
The Peninsular Plateau is characterized by relict and residual mountains like the Aravali hills, which are ancient and have been subjected to extensive erosion.
A.
Young fold mountains
B.
Ancient gneisses and granites
C.
Volcanic islands
D.
Alluvial plains
Correct Answer: B
Solution:
The Peninsular Block is primarily formed of ancient gneisses and granites.
True or False
Correct Answer: True
Solution:
Western Ghats are locally known by different names such as Sahyadri in Maharashtra.
Correct Answer: True
Solution:
The Indian plate's northward movement is ongoing and has significant consequences on the physical environment of the Indian subcontinent.
Correct Answer: False
Solution:
The Peninsular Plateau is characterized by features like tors, block mountains, and rift valleys, not fertile alluvial soil, which is typical of the Northern Plains.
Correct Answer: True
Solution:
The Northern Plains are formed by the alluvial deposits brought by the rivers Indus, Ganga, and Brahmaputra.
Correct Answer: True
Solution:
The Western Ghats are comparatively higher in elevation and more continuous than the Eastern Ghats.
Correct Answer: False
Solution:
The Indian plate was originally located to the south of the equator millions of years ago.
Correct Answer: False
Solution:
The Western Ghats are more continuous and have a higher elevation compared to the Eastern Ghats.
Correct Answer: False
Solution:
The Western Ghats are more continuous and have a higher elevation compared to the Eastern Ghats.
Correct Answer: True
Solution:
The Peninsular India is made up of a series of plateaus and is one of the oldest and most stable landmasses of India.
Correct Answer: True
Solution:
The Meghalaya plateau is rich in mineral resources like coal, iron ore, sillimanite, limestone, and uranium.
Correct Answer: False
Solution:
The eastern coastal plains are broader and are an example of an emergent coast, unlike the narrower western coastal plains.
Correct Answer: True
Solution:
The Western Ghats are comparatively higher in elevation and more continuous than the Eastern Ghats.
Correct Answer: False
Solution:
The Great Indian Desert receives low rainfall below 150 mm per year and has an arid climate with low vegetation cover.
Correct Answer: True
Solution:
The Indo-Ganga-Brahmaputra Plain was originally a geo-synclinal depression.
Correct Answer: True
Solution:
Current estimation shows that the earth is approximately 4600 million years old.
Correct Answer: True
Solution:
The Peninsular Block is formed essentially by a great complex of very ancient gneisses and granites.
Correct Answer: True
Solution:
Current estimation shows that the earth is approximately 4600 million years old.
Correct Answer: False
Solution:
The western coastal plains are an example of a submerged coastal plain, not an emergent coast.
Correct Answer: True
Solution:
The Western Ghats are comparatively higher in elevation and more continuous than the Eastern Ghats.
Correct Answer: True
Solution:
The Indo-Ganga-Brahmaputra Plain is a featureless plain with a general elevation of 50-150 m above mean sea level.
Correct Answer: True
Solution:
The Ten degree channel is the waterbody that separates the Andaman Islands from the Nicobar Islands.
Correct Answer: False
Solution:
The Indian plate was originally located to the south of the equator, not the north.
Correct Answer: True
Solution:
The Peninsular Plateau is one of the oldest and most stable landmasses of India.
Correct Answer: False
Solution:
Barren Island, the only active volcano in India, is situated in the Nicobar islands.
Correct Answer: True
Solution:
The Peninsular India is made up of a series of patland plateaus such as the Hazaribagh plateau, the Palamu plateau, the Ranchi plateau, etc.
Correct Answer: True
Solution:
The Meghalaya plateau is indeed rich in mineral resources such as coal, iron ore, sillimanite, limestone, and uranium.
Correct Answer: True
Solution:
The Western Ghats are generally higher in elevation than the Eastern Ghats, with peaks such as Anaimudi reaching 2,695 meters.
Correct Answer: True
Solution:
The Andaman and Nicobar Islands are separated by a waterbody called the Ten degree channel.
Correct Answer: True
Solution:
The Peninsular Block is indeed formed by a great complex of very ancient gneisses and granites, which constitutes a major part of it.
Correct Answer: False
Solution:
Most of the rivers in the Indian Desert region are ephemeral, meaning they do not flow year-round.
Correct Answer: True
Solution:
The Peninsular Block has remained a rigid structure since the Cambrian period, with only some parts affected by tectonic activity.
Correct Answer: True
Solution:
Western Ghats are comparatively higher in elevation and more continuous than the Eastern Ghats.
Correct Answer: True
Solution:
The Andaman and Nicobar Islands are separated by a waterbody called the Ten degree channel.
Correct Answer: True
Solution:
The Peninsular Plateau is formed essentially by a great complex of very ancient gneisses and granites.
Correct Answer: True
Solution:
The Northern Plains are indeed formed by the alluvial deposits brought by the rivers Indus, Ganga, and Brahmaputra.
Correct Answer: True
Solution:
The Meghalaya plateau is rich in mineral resources like coal, iron ore, sillimanite, limestone, and uranium.
Correct Answer: True
Solution:
The Indo-Ganga-Brahmaputra Plain was originally a geo-synclinal depression which attained its maximum development during the third phase of the Himalayan mountain formation.
Correct Answer: True
Solution:
The eastern coastal plains have well-developed deltas formed by the Mahanadi, Godavari, Krishna, and Kaveri rivers.
Correct Answer: True
Solution:
The Ten degree channel separates the Andaman Islands in the north from the Nicobar Islands in the south.