Geography

As per the new textbook prescribed

by Maharashtra State Board
A biome can be defined as the total
assemblage of plant and animal species
interacting within specific conditions.

... .

Tar et ®
Publications Pvt. Ltd.
 Written as per the latest textbook prescribed by the Maharashtra State Bureau of Textbook
Production and Curriculum Research, Pune.

PERFECT
Geography

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Std. XI

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Salient Features

 Based on the new textbook

 Exhaustive content coverage in Question and Answer format
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 Wide variety of questions in each chapter (including map based questions)
 ‘Chapter Overview’ enables quick revision of key points
 Includes ‘Gyan Guru’ (GG) that offers a practical touch to theory
 ‘For your understanding’ section aids conceptual clarity
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 Includes ‘Smart Codes’ to enable easy answer recall
 Includes ‘QR Codes’ to refer relevant content
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 Coverage of the ‘Apply Your Knowledge’ section

 Chapter assessment at the end of every chapter for self evaluation with answer key
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Printed at: Print to Print, Mumbai

© Target Publications Pvt. Ltd.
No part of this book may be reproduced or transmitted in any form or by any means, C.D. ROM/Audio Video Cassettes or electronic, mechanical
including photocopying; recording or by any information storage and retrieval system without permission in writing from the Publisher.

Balbharati Registration No.: 2018MH0022 P.O. No. 1465

TEID: 1842
 PREFACE

Perfect Geography Std. XI has been designed to provide accurate information regarding physical
geography in accordance with the syllabus. It is based on the latest curriculum developed by the
Maharashtra State Bureau of Textbook Production and Curriculum Research, Pune. It includes the
fundamentals of geomorphology, oceanography, climatology and biogeography in a foundational
framework for understanding development patterns in different parts of the earth.
The study of physical geography becomes imperative because it is the study of structure, processes
and interactions between physical and human environment. The key features of the book include

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Chapter Overview, Gyan Guru, For your understanding, Map based question, Smart Codes, QR Codes
and Chapter Assessment. These concepts would not only help the student remember and understand
the basics but also help them internalise and evaluate it with utmost amount of involvement.
Also, the latest education policy recommends that students’ life at the educational institution must

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be linked to their life outside it as well. This principle marks the departure of the legacy of rote
learning which continues to shape our system and causes a gap among the school, home and
community. The syllabi and textbooks developed on the basis of the new education policy signify an
attempt to implement this basic idea and enhance a student’s learning experience.

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We hope that the students as well as teachers find this book lucid and purposeful.

- Publisher
Edition : First
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The journey to create a complete book is replete with triumphs, failures and near misses. If you think
we’ve nearly missed something or want to applaud us for our triumphs, we’d love to hear from you.
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Please write to us at: mail@targetpublications.org
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Disclaimer
This reference book is transformative work based on textbook ‘Geography’: First edition: 2019 published by the Maharashtra State Bureau of
Textbook Production and Curriculum Research, Pune. We, the publishers are making this reference book which constitutes as fair use of textual
contents which are transformed by adding and elaborating, with a view to simplify the same to enable the students to understand, memorize and
reproduce the same in examinations.
This work is purely inspired upon the course work as prescribed by the Maharashtra State Bureau of Textbook Production and Curriculum Research, Pune.
Every care has been taken in the publication of this reference book by the Authors while creating the contents. The Authors and the Publishers shall not be
responsible for any loss or damages caused to any person on account of errors or omissions which might have crept in or disagreement of any third party on
the point of view expressed in the reference book.
© reserved with the Publisher for all the contents created by our Authors.
No copyright is claimed in the textual contents which are presented as part of fair dealing with a view to provide best supplementary study material for
the benefit of students.
 FEATURES

Chapter Overview
Chapter Overview
1. A biome is an area where different types of
flora and fauna live together in the same
region in the same type of climatic conditions. After reading a chapter from textbook,
2. The boundaries of different biomes on land students may want to revise all key points
Biomes

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are mainly determined by climatic conditions quickly before attempting questions based
such as rainfall, temperature, humidity, on the chapter. ‘Chapter overview’ gives a
amount of insolation received and soil bird’s eye-view of the entire chapter.
conditions.

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Apply Your Knowledge
Map based question 1. Make friends with maps! (Textbook pg. no 75)
Look at figure 7.1 and answer the following

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questions:
Map based questions are included as per
i. What does this map show?
the necessity of the chapter.
Ans: i. This map shows the relief of Indian Ocean floor.
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GG - Gyan Guru GG – Gyan Guru

Water displays unusual behaviour when Gyan Guru, our very own mascot, keeps
cooled below 4° C. Instead of contracting, it popping up throughout the book. He offers
expands. Hence, ice, being less dense, floats
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real-life example or an interesting fact
on water.
associated with the topic.
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For your understanding For your understanding

‘Tsunami’, in Japanese, means ‘harbour wave’. They are

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Certain concepts are tricky and difficult colossal waves, caused mostly by earthquakes or volcanic
to understand. In such cases, ‘For your eruptions, in water bodies. These waves can reach heights of
understanding’ offers better conceptual up to 100 feet. Their impact is limited to coastal areas but
clarity. their destructive power is enormous.
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Smart Code A I S R O

i. Asymmetrical: The axial plane is inclined. The

Smart Code
limbs are inclined at different angles.
ii. Isoclinal: The limbs slope in the same direction
with same amount. The axial plane may be At times, answers are lengthy and it’s
vertical, inclined or horizontal. Slope of some difficult to remember all the points. Hence,
portion of limbs is near vertical. we have created Smart Codes for a few
iii. Symmetrical: The axial plane is vertical. Limbs questions to aid you in remembering and
are inclined at same angle. recollecting these points.
 FEATURES

QR Code
[Note: Scan QR code to watch key
QR codes given throughout the book messages from the IPCC’s special report
enable students to access relevant on the impact of global warming.]

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content for the given topic.

Chapter Assessment

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Time: 1.00 Hr. Total Marks: 20
Q.1. (A) Fill in the blanks with appropriate
alternatives given below and rewrite the Chapter Assessment
sentences. [3]

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1. _______ is a submarine canyon found near
Africa.
Chapter assessment at the end of
(A) Madagascar canyon (B) Zaire canyon every chapter enables students to
(C) Congo canyon (D) Egypt canyon evaluate themselves. This evaluation
becomes more effective with the help
Answers of the answer key.
Q.1. (A) 1. (C)
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CONTENTS
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No. Topic Name Page No.

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1. Earth Movements 1
2. Weathering and Mass Wasting 17
3. Agents of Erosion 31
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4. Climatic Regions 49
5. Global Climate Change 70
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6. Ocean Resources 83
7. Indian Ocean - Relief and Strategic Importance 97
8. Biomes 111
9. Disaster Management 134

Note: 1. All textual questions are represented by * mark.

2. All questions based on intext content are represented by # mark.
 1 Earth Movements

Chapter Overview
1. Landforms like hills, mountains, plateaus, valleys, etc., are developed and shaped by the

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internal and external forces of the earth.
Earth
2. Evidence suggests that landforms are never permanent and earth movements have always
movements
affected them.
3. The internal processes are classified into slow movements and sudden movements.
1. Based on the direction of earth’s slow movements, they can be epeirogenic (i.e., vertical /

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continent-building) or orogenic (i.e. horizontal / mountain-building).
2. Orogenic movements may be due to tensional forces (forming faults) or compressional forces
Slow (forming folds).
movements 3. Fold mountains are formed due to the following types of folds: symmetrical, asymmetrical,

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overturned, recumbent and isoclinal.
4. Block mountains and rift valleys are formed due to the following types of faults: normal,
reverse, tear and thrust.
1. Sudden movements cause earthquakes and volcanoes.
2. The waves associated with earthquakes are: P-waves, S-waves and L-waves.
3. Shadow zones are specific areas where these seismic waves are not reported.
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4. The strength of an earthquake can be expressed in the Mercalli or the Richter scale.
5. Some causes of earthquakes are: Volcanicity, Tectonic Movements and Anthropogenic causes.
Sudden
6. Volcanoes are of various types: (i) Conical and Fissure (ii) Active, Dormant and Dead
movements
7. Materials which come out of volcano: liquid, solid, gaseous
8. Volcanic landforms include: Lava domes, Lava Plateaus, Calderas, Crater lakes, Volcanic plugs,
Cinder cones and Composite cones.
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9. Areas most prone to earthquakes and volcanoes are: Circum-Pacific Belt, Mid-Atlantic belt
and Mid-Continental belt.
Q.1. [A] Fill in the blanks with appropriate 4. Orogenic movements are also known as
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alternatives given below and rewrite _______ movements.

the sentences (A) slow (B) sudden
(C) horizontal (D) vertical
1. Earth movements are _______.
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(A) very complex and interrelated 5. _______ forces operate towards each other and
(B) simple and independent of each other cause compression.
(C) hypothetical (A) Converging (B) Tensional
(D) non-dynamic (C) Sudden (D) Diverging
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#2. The _______ earthquake of 1819 submerged 6. In case of _______, limbs of the fold slope
the coastal areas and gave rise to a raised land upward while the central portion is lower.
called Allah’s Bund. (A) syncline (B) anticline
(A) Uttarkashi (B) Kachchh (C) folds (D) faults
(C) Assam (D) Himachal
7. The height of Mt. Everest is _______ (AMSL).
3. Tectonic movements are defined as movements (A) 10,200 m (B) 4,568 m
of _______. (C) 6,023 m (D) 8,848 m
(A) fold mountains
(B) air currents in different strata of 8. Limbs slope in the same direction with the same
atmosphere amount in case of _______ folds.
(C) the earth’s surface due to internal forces (A) isoclinal (B) overturned
(D) block mountains (C) asymmetrical (D) recumbent
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Std. XI: Perfect Geography

9. Graben means _______. (C) Lava domes, Caldera, Anticline, Cinder cone
(A) rift valley (B) block mountain (D) Lava domes, Caldera, Crater lake, Lava river
(C) fold Mountain (D) volcano Answers:
10. The earthquake waves are recorded by an 1. (B) 2. (A)
instrument called _______. Q.1. [C] Complete the chain
(A) seismograph (B) anemometers
(C) Richter Scale (D) barometer *1.
#11. An imaginary line on a map, connecting the A B C

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places of uniform intensity of earthquake is 1. Widespread i. Zone V a. I to XII
called _______ line. volcanic
(A) isothermal (B) isobar eruption
(C) isoseismal (D) iso quake 2. Andaman ii. Fissure b. Block
#12. The energy released in an earthquake of and Nicobar eruption Mountain

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magnitude 5 is _______ times more than that of Islands
magnitude 4. 3. Mercalli iii. Intensity c. Very high
(A) 2 (B) 4 (C) 10 (D) 32 scale seismic
#13. In 1927, a new island was created near Java due vulnerability

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to volcanic eruption, where the island of 4. Slow iv. Faulting d. Solid
Krakatoa had disappeared earlier. This new movements
island was named ________. 5. Philippines v. Volcanic e. Deccan Trap
(A) Anak Krakatoa (B) Child Island bombs
(C) Java Krakatoa (D) Sumatra 6. Volcanic vi. Circum- f. Mayon
material Pacific belt
14. Deccan trap in India is an example of ________.
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(A) block mountain (B) rift valley Ans: (1-ii-e), (2-i-c), (3-iii-a), (4-iv-b), (5-vi-f), (6-v-d)
(C) lava plateau (D) caldera
Q.1. [D] Identify the correct correlation
15. The highest volcanic mountain in the world is
________.
(A) Cotopaxi (B) Mt. Everest *A: Assertion, R: Reasoning
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(C) Fujiyama (D) Kilimanjaro (a) Only A is correct.
(b) Only R is correct.
Answers: (c) Both A and R are correct and R is the correct
1. (A) 2. (B) 3. (C)
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explanation of A.
4. (C) 5. (A) 6. (A) (d) Both A and R are correct but R is not the
7. (D) 8. (A) 9. (A) correct explanation of A.
10. (A) 11. (C) 12. (D) [Note: Above options are for all questions given
13. (A) 14. (C) 15. (A) below.]
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Q.1. [B] Choose the correct alternative 1. A: Faulting leads to development of fold
mountains.
1. Causes of earthquake:
R: Faulting occurs when tensional forces move
(A) Landslide, Volcanicity, Vertical
away from each other.
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movements, Large scale mining

Ans: (b)
(B) Tectonic movements, Volcanicity,
Blasting, Atomic explosion 2. A: Intensity of an earthquake is a measurement
(C) Volcanicity, Horizontal movements, of the energy released during an earthquake.
Compression, Large scale mining R: Mercalli scale is used to measure the
(D) Drilling, Tectonic movements, Tsunami, intensity of an earthquake.
Landslide Ans: (b)
2. Volcanic landforms: 3. A: South-East Asia, Japan and islands in the
(A) Lava domes, Caldera, Crater lake, Cinder Pacific Ocean are most vulnerable to
cone earthquakes and volcanic eruptions.
(B) Lava domes, Lava river, Crater lake, R: They are located in ‘Ring of Fire’.
Cinder cone Ans: (c)
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Chapter 1: Earth Movements

Q.1. [E] Identify the correct group 9. The materials which come out of volcano are:
(A) Basic lava (B) Volcanic bombs
*1. i. a. Symmetrical fold (C) Magma (D) Lava domes
b. Isoclinal fold
10. Examples of volcanic mountains in the Ring of
c. Overturned fold
Fire are:
d. Recumbent fault
(A) Fujiyama, Japan
ii. a. Black Forest b. Vosges (B) Mt. St. Helens, USA
c. Himalayas d. Satpuras (C) Stromboli, Italy
(D) Pinatubo and Mayon, Philippines

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iii. a. Narmada Valley b. African Valley
Answers:
c. Tapi Valley d. Rhine Valley
1. (B) 2. (D) 3. (C)
iv. a. Caldera b. Crater Lake 4. (A) 5. (D) 6. (B)
c. Cinder Cone d. Lava plateau 7. (A) 8. (C) 9. (D)

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Ans: iv. 10. (C)

Q.1. [F] Identify the incorrect factor Q.1. [G] Arrange the given statements as per
given instructions
1. The mountain ranges in the Himalayas are:
Arrange the following in proper chronological order.

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(A) The Siwaliks
1. i. Collapse of buildings
(B) The Aravallis
ii. Shaking of the ground
(C) The Middle Himalayas
iii. Rehabilitation measures
(D) The Greater Himalayas
iv. Stress in the rock strata
2. The nature of folding on the earth’s surface 2. i. Ejection of molten lava
depends on: ii. Formation of caldera
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(A) Nature of rocks iii. Magma cooling and solidification
(B) Intensity of force iv. Formation of crater lake
(C) Duration of force Answers:
(D) Rotation of earth 1. iv, ii, i, iii 2. i, iii, ii, iv
3. The different parts of fold are:
Q.2. Give geographical reasons
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(A) Limb (B) Anticline
(C) Fracture (D) Syncline 1. Slow vertical movements are called
continent-building movements.
4. The plane of the crack in rock strata, during
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Ans: i. Slow (epeirogenic) movements keep on

faulting, is called:
taking place either towards the centre of
(A) folds (B) rupture
the earth or towards the earth’s crust.
(C) fracture (D) fault
ii. Due to such movements, an extensive
5. The types of faults are: portion of the crust is either raised up or it
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(A) Normal (B) Reverse subsides.

(C) Tear (D) Asymmetrical iii. When a portion of the crust is raised above
sea-level, it leads to the formation of
6. Examples of block mountains are:
continents.
(A) Meghalaya Plateau, India
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Hence, slow vertical movements are called

(B) Alps, Europe
continent-building movements.
(C) Vosges, France
(D) Black Forest, Germany *2. Soft rocks form folds while hard rocks form
faults.
7. The waves associated with earthquakes are:
Ans: i. Soft rocks, deep within the crust, are
(A) M-waves (B) P-waves
flexible and under high pressure.
(C) S-waves (D) L-waves ii. Hence, they fold easily due to
8. Earthquakes due to tectonic movements occur in: compressional (converging) forces.
(A) Assam, India iii. Hard rocks, near the earth's surface, are
(B) Chile, South America rigid and not under high pressure.
(C) Doha, Qatar iv. Hence, they form faults easily due to
(D) California, USA tensional forces.
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Std. XI: Perfect Geography

*3. Folds depend on the strength of rocks and
GG - Gyan Guru
intensity of forces.
Ans: i. Soft and elastic rocks are affected more by
compressional forces. The earth’s rigid outer part is made up
of many tectonic plates. These plates
ii. The rocks react to compressional force
keep drifting very slowly.
depending on their strength and the speed
Until 175 million years ago, the earth
of the force.
had just one supercontinent called
iii. When compressional forces are applied on
‘Pangea’. According to Theory of
ductile or flexible rocks, folding occurs.

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Continental Drift, tectonic movements
These rocks are particularly susceptible to
are responsible for the existence of
folding without breaking.
the 7 current continents.
iv. Folding is more likely to occur where These movements will change the
compressional forces are applied slowly. shape and position of the continents in

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*4. L-waves do not have a shadow zone. the future too.
Ans: i. Earthquake waves get recorded in
seismographs located at far off locations. *6. Extinct conical volcanoes often form crater
However, there are some specific areas lakes.

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where the seismic waves of an earthquake Ans: i. At times, the eruption of volcano brings
are not reported. Such zones are called about a large quantity of material and
shadow zones. relieves lot of pressure.
ii. Generally, seismographs located at any ii. After a volcanic eruption, a large and deep
distance within 105 from the epicentre depression called caldera may remain in
record the arrival of both, P-waves and that area. This can be around 10 m wide
and hundreds of metres deep.
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S-waves. However, the seismographs
located beyond 140° from the epicentre; iii. A smaller caldera is known as crater.
record the arrival of P-waves, but not that iv. When the funnel-shaped crater of an
of S-waves. Thus, a zone between 105 extinct volcano is filled with rain water, it
and 140 from the epicentre is identified forms a crater lake.
as the shadow zone for both the types of
Q.3. Differentiate between
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waves.
iii. The entire zone beyond 105 does not *1. Slow movements and Sudden movements
receive S-waves. The shadow zone of Ans:
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P-waves appears as a band around the

earth between 105 and 140 away from No. Slow movements Sudden movements
the epicentre. i. Slow movements Sudden movements
iv. As L-waves travel in the direction of occur over hundreds occur over short
of years. periods of time (few
m

circumference of the along the earth crust,

and not inwards, these waves do not have a seconds to several
shadow zone. hours).
ii. They cause continent- They cause
*5. People living in the Himalayas are more building, folding and earthquakes and
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vulnerable to earthquakes. faulting. volcanoes.

Ans: i. The Himalayan region is one of the most
2. Epeirogenic movements and Orogenic
seismically active regions or active
movements
earthquake zone in the world.
Ans:
ii. The Himalayas lie at the fault line between
the Indo-Australian plate and the Eurasian Epeirogenic Orogenic
No.
plate. movements movements
iii. Tectonic movements between these i. Epeirogenic Orogenic movements
plates make this place vulnerable to movements are slow are slow horizontal
earthquakes. vertical movements movements in the
Hence, people living in the Himalayas are more in the interior of the interior of the earth.
vulnerable to earthquakes earth.

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Chapter 1: Earth Movements

ii. Although these These movements are vi. Types of folds: Types of faults:
movements occur also slow, but their Symmetrical, Normal, Reverse,
very slowly; they lead speed is more than the Asymmetrical, Tear, Thrust
to formation of epeirogenic movements. Overturned,
continents and They lead to formation Recumbent, Isoclinal
extensive plateaus. of fold mountains, block
*5. Syncline and Anticline
mountains and rift
Ans:
valleys.
iii. They influence huge They influence smaller No. Syncline Anticline

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areas. areas. i. In case of syncline, In case of anticline,
iv. They don’t occur due They occur due to limbs of the fold slope limbs of the fold
to tensional and tensional and upwards while the slope downwards
compressional forces. compressional forces. central portion is lower. while the central
portion is raised up.

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3. Tensional forces and Compressional forces ii. Its trough forms a Its crest forms a
Ans: valley. mountain.
Tensional (Diverging) Compressional iii. [Note: Students are expected to refer Q.6.(1)
No.
forces (Converging) forces for diagrams.]
i. Tensional forces Compressional forces

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operate away from operate towards each *6. Asymmetrical fold and Symmetrical fold
each other and cause other and cause Ans:
stress in the rock pressure on the rock No. Asymmetrical fold Symmetrical fold
strata. strata. i. Axial plane is inclined. Axial plane is vertical.
ii. They create faults in They create folds in ii. Limbs are inclined at Limbs are inclined at
the earth’s crust. the earth’s crust. different angles. the same angle.
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iii. They form block They form fold iii. [Note: Students are expected to refer Q.6.(2-i,
mountains and rift mountains. iii) for diagrams.]
valleys.
*7. Normal fault and Reverse fault
Tension Compression Ans:
iv.
No. Normal fault Reverse fault
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i. Normal fault results Reverse fault results
Compression
Tension when a portion of land when a portion of the
slides down along the land is thrown
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fault plane. upward relative to

other side of the land.
*4. Folding and Faulting ii. Here, the exposed Here, the exposed
Ans: portion of the fault portion of the fault
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No. Folding Faulting plane faces the sky. plane faces the
i. Folding is caused by Faulting is caused by ground.
compressional forces. tensional forces. iii. [Note: Students are expected to refer Q.6.(3-i,
ii. It occurs in soft and It occurs in hard and ii) for diagrams.]
elastic rocks. rigid rocks.
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iii. It occurs in rocks at a It occurs in rocks at a 8. Horst and Graben

greater depth inside lesser depth inside Ans:
the earth’s surface. the earth’s surface. No. Horst (Block mountain) Graben (Rift valley)
iv. It can be classified It can be classified i. Horst is formed when Graben is formed
based on the based on the the block enclosed by due to subsidence in
inclination of its axial displacement of the faults rises or the land the central portion
plane and limbs. rocks. on either side subsides. of the crust between
v. It forms fold It forms block two adjacent faults.
mountains. (E.g. the mountains (E.g. the ii. E.g. Satpuras, Black E.g. Tapi and
Himalayas) Satpuras) and rift Forest Mountain Narmada valley
valleys. (E.g. Narmada iii. [Note: Students are expected to refer Q.6.
valley) (4 and 5) for diagrams.]
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 

Std. XI: Perfect Geography

9. Fold mountain and Block mountain 2. Classification of fold mountains depending on
Ans: their age
No. Fold mountain Block mountain Ans: i. Folding leads to development of fold
i. Fold mountain is Block mountain is mountains.
caused by caused by tensional ii. Old fold mountains are over 200 million
compressional forces. forces. years of age. e.g. the Aravalli in India, the
ii. It has less steep It has very steep Urals in Russia and the Appalachians in
slopes. slopes. USA.
iii. It has a peak. (E.g. the It has a flat top. (E.g. iii. Young fold mountains are between 10 to 25

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Himalayas) the Satpuras) million years of age. e.g. the Himalayas in
India, the Rockies in USA and the Andes in
*10. Mercalli scale and Richter scale South America.
Ans:
3. Earthquake

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No. Mercalli scale Richter scale Ans: i. Movements in the earth’s crust generate a
i. Mercalli scale Richter scale lot of stress in the rock strata. When this
measures the measures the energy stress accumulates beyond a limit, it tends
intensity of an released during an to get released in the crust in the form of
earthquake. earthquake. energy.

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ii. It is based on the It is based on the ii. Release of energy waves causes the earth’s
observation of the logarithm of the crust to shake, which is called an
effects on earth’s amplitude of the wave earthquake.
surface, humans, measured by a iii. The point where the accumulated stress in
objects and seismograph. the rock strata gets released within the
structures. earth’s crust is called seismic focus. The
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iii. It ranges from I (not It ranges from <2.0 to point directly above seismic focus, on the
felt) to XII (total 10.0+ (never earth’s surface, is called epicentre.
destruction). recorded). iv. The intensity of the shock is the maximum
at the epicentre and decreases with
11. Acidic lava and Basic lava
increasing distance from the epicentre in all
Ans:
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directions.
No. Acidic lava Basic lava v. The instrument to record earthquake waves
i. Acidic lava contains a Basic lava contains a is called a seismograph.
higher percentage of lesser percentage of
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silica. silica. 4. Causes of earthquakes

ii. It has a high melting It has a low melting Ans. i. Volcanicity: Sometimes, shallow
point. point. earthquakes occur in areas close to the
volcanic eruption site. e.g. Earthquake in
iii. It is less fluid and It is more fluid and
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the Cascades near Mt. St. Helens, USA in

flows over shorter flows over longer
1981 (magnitude: 5.5)
distances. distances.
ii. Tectonic movements: Due to the
Q.4. Write short notes on movement of tectonic plates of the crust,
floating on the upper mantle, earthquakes
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1. Parts of a fold occur along their margins (divergent and

Ans: i. Folds develop in the earth’s crust. convergent). e.g. Earthquake in Gujarat,
ii. Both sides of a fold are called limbs. India in 2001. The earthquakes which
iii. The axial plane divides a fold into two parts. generally occur in Indonesia, California,
The axis may be vertical, inclined or Chile, Uttarkashi and Assam can be
horizontal. attributed to tectonic movements.
iv. In case of anticline, limbs of the fold slope iii. Anthropogenic causes: Localized
downwards while the central portion is earthquakes may occur due to human
raised up. The opposite is true in case of activities like atomic explosion, drilling,
syncline. mining, blasting, large-scale construction,
[Note: Students are expected to refer Q.6.(1) for etc. e.g. Earthquake due to North Korean
diagram.] nuclear test in 2017.
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Chapter 1: Earth Movements

5. Volcanoes 6.6 hit within 80 minutes of the quake. This is the
Ans: i. Volcano is an opening in the earth’s surface largest earthquake in Nepal after 80 years. India has
through which gases, molten lava and solid sent rescue teams immediately.
material are ejected from the upper mantle
1. What was the magnitude of the earthquake?
to the earth’s surface.
Ans: The magnitude of the earthquake was 7.9 on
ii. Volcanoes are caused due to sudden
movements. Richter scale.
iii. On the basis of the origin of eruption, they 2. Where was the epicentre of the earthquake?
are classified as: cone volcanoes and fissure

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Ans: The epicentre of the earthquake was Lamjung,
volcanoes. which is around 80 kilometres northwest of
iv. On the basis of periodicity and continuance Kathmandu.
of eruption activity, they are classified as:
active, dormant or extinct (dead). 3. Which are the other affected areas?

te
6. Major belts of earthquakes and volcanoes Ans: Other affected areas include several cities in
Bihar, West Bengal and Uttar Pradesh.
Ans: The three major belts or zones of earthquake
and volcanoes on the earth are as follows: 4. According to you, what could be the reason
i. Circum-Pacific Belt: It is called the ‘Ring of behind the earthquake?

on
Fire’. It includes the volcanoes of Eastern Ans: It was probably due to tectonic movements. It
and Western coastal areas of the Pacific could also have been due to anthropogenic
Ocean. Cotopaxi, the highest volcanic causes like large scale drilling.
mountain of the world, is found in this belt.
ii. Mid-Atlantic Belt: It covers the Mid-Atlantic Q.6. Draw neat and labelled diagrams for
Ridge. The most active volcanic area is
1. Parts of a fold
C
Iceland which is found on Mid-Atlantic
ridge. Ans:
iii. Mid-Continental Belt: It includes the limb
volcanoes of Alpine mountains,
Mediterranean Sea and the Easter Africa Anticline Anticline
fault zone. Stromboli and Etna, Italy are
e
famous volcanoes.
Axis of the Horizontal plane
Q.5. Read the following extract and answer the fold Syncline
pl

questions given below Axial plane

Parts of fold
Kathmandu : 25 Apr (PTI)
A powerful earthquake measuring 7.9 on *2. Types of folds
Richter scale struck Nepal today, nearly 1500 people
m

Ans: Prior to folding

were killed and over 1000 people were injured in the
disaster.
The quake and a series of serious aftershocks
delivered a severe blow to Nepal. The tremors were
Sa

also felt across vast stretches of east and northeast

India. It was also felt in China, Bhutan and as far as
Pakistan and Bangladesh. The earthquake with
epicentre at Lamjung, around 80 kilometres northwest
of Kathmandu, had its impact in several cities in Bihar,
West Bengal and Uttar Pradesh.
The initial report said the tremor measured
7.9-magnitude. It said the quake hit at 11:40 am local
time at a shallow depth of 11 km. ‘‘There were
17 major aftershocks measuring over 5 in the next two
and half hours,” said an officer of the National
Seismological Centre. Another aftershock measuring i. Symmentrical

7
 

Std. XI: Perfect Geography

iii.

Thrust fault

ii. Isoclinal iv.

nt
te
Tear fault

4. Block mountain
iii. Asymmetrical Ans:

on
C
5. Rift valley
iv. Recumbent Ans:
e
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*6. Shadow zone

v. Overturned Ans:
Epicenter
m

*3. Types of faults

Ans: i.
Sa

Liquid Solid
outer Inner core
Normal fault A core
105 P-wave P-wave 105
shadow shadow
ii. zone zone
B

140 140
C Crust
No direct P-wave
S-waves S-wave
Reverse fault
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 

Chapter 1: Earth Movements

*7. Volcanic landforms vii. Composite cone
Ans: i. Lava domes

Q.7. Answer in detail

nt
ii. Lava plateaus 1. State some evidence of earth movements.
Ans: i. After the Great Tsunami of 2004, the coast
around Sumatra Island rose by a few
centimetres.

te
ii. The Himalayas were formed millennia ago
due to tectonic movements which continue
even today.
iii. In 1963, some sailors witnessed the

on
formation of an island due to volcanic
eruption near Iceland.
iii. Calder iv. In 2004, islands such as the Megapode
Island were reported to have been lost after
the tsunami.
v. To the south east coast of Mumbai, near
C
Mazagaon Dockyard, there is evidence of
forest-covered land getting drowned.
For your understanding
iv. Crater lake ‘Tsunami’, in Japanese, means ‘harbour wave’. They
are colossal waves, caused mostly by earthquakes
e
or volcanic eruptions, in water bodies. These waves
can reach heights of up to 100 feet. Their impact is
limited to coastal areas but their destructive power
pl

is enormous.

2. Explain different types of folds.

Ans:
Smart Code A I S R O
m

v. Volcanic plug
i.Asymmetrical: The axial plane is inclined.
The limbs are inclined at different angles.
ii. Isoclinal: The limbs slope in the same
direction with same amount. The axial plane
Sa

may be vertical, inclined or horizontal. Slope

of some portion of limbs is near vertical.
iii. Symmetrical: The axial plane is vertical.
Limbs are inclined at same angle.
vi. Cinder cone iv. Recumbent: Axial plane is almost
horizontal. One limb lies over the other in
horizontal direction.
v. Overturned: One limb lies above the other
limb. Limbs slope unequally in the same
direction.
[Note: Students are expected to refer Q.6.(2) for
diagrams.]
9
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Std. XI: Perfect Geography

*3. Explain different types of faults. and not inwards, these waves do not have a
Ans: i. Normal fault: It results when a portion of shadow zone.
land slides down along the fault plane and [Note: Students are expected to refer Q.6.(6) for
when the exposed portion of the plane diagram.]
faces the sky. *5. Write a note on volcanic materials.
ii. Reverse fault: It results when a portion of Ans: i. Solid material: It consists of dust particles
the land is thrown upward relative to other and rock fragments.
side of the land. In such situation, the fault a. Volcanic dust: Very fine dust particles
plane faces the ground.

nt
b. Ash: Small-sized particles
iii. Tear fault: At times, the rock strata on c. Cinders: Half-burnt pieces of solid
either sides of the fault plane do not have material
vertical displacement. Instead movement d. Breccia: Solid angular fragments
occurs along the plane in horizontal e. Volcanic bombs: Small fragments falling

te
direction. on the earth, formed when lava
iv. Thrust fault: When the portion of the land material solidify when thrown into the
on one side of the fault plane gets detached air.
and moves over land on the other side. The ii. Liquid material:
angle of fault plane is generally low (less

on
a. Magma: Molten rock material below
than 45). the earth’s surface.
[Note: Students are expected to refer Q.6.(3) for b. Lava: Molten rock material on the
diagrams.] earth’s surface.
c. It is classified into acidic lava and basic
*4. Explain the concept of shadow zone. lava based on the percentage of silica.
C
Ans: i. Earthquake waves get recorded in Acidic lava contains higher percentage
seismographs located at far off locations. of silica while basic lava contains less
But shadow zones are areas on the earth’s percentage of silica.
surface where the seismic waves of an iii. Gaseous material:
earthquake are not reported. a. During an eruption, a dark,
ii. Each earthquake has different shadow zone. cauliflower-shaped cloud is seen over
e
The shadow zone can be drawn based on the crater.
the location of epicentre. b. It comprises smoke and inflammable
iii. Generally, seismographs located at any gases, which produce flames.
pl

distance within 105 from the epicentre

*6. Explain, with examples, different types of
record the arrival of both, P-waves and
landforms produced by volcanic eruption.
S-waves. However, the seismographs
Ans: i. Lava domes: Domes are developed when
located beyond 140° from the epicentre;
m

magma comes out and solidifies around its

record the arrival of P-waves, but not that
mouth. The shape of the dome depends
of S-waves. Thus, a zone between 105
upon the fluidity of lava. High domes with
and 140 from the epicentre is identified
steep slopes are developed by acidic lava.
as the shadow zone for both the types of
Low domes with a broad base are
waves.
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developed by basic lava. e.g. Mt. Elden in

iv. The entire zone beyond 105 does not Arizona.
receive S-waves. The shadow zone of ii. Lava plateaus: Due to spread of lava in
S-waves is much larger than that of the huge quantity from fissure volcano, it
P-waves. covers large areas and plateaus are formed.
v. The shadow zone of P-waves appears as a e.g. Deccan Trap in India.
band around the earth between 105 and iii. Caldera: After volcanic eruption, a large and
140 away from the epicentre. deep depression remains in that area, called
vi. The shadow zone of S-waves is larger in caldera. Caldera can be around 10 km wide
extent. and hundreds of metres deep. e.g. Mt.
vii. As L-waves travel in the direction of Katmai in USA. Smaller caldera is called
circumference of the along the earth crust, crater.

10
 

Chapter 1: Earth Movements

iv. Crater lake: When the funnel shaped crater 3. Think about it. (Textbook pg. no 4)
of an extinct volcano is filled with rain ‘A mountain never remains a mountain’.
water, its forms a crater lake. e.g. Lonar lake Can you relate this idiom with the mountain
in India. building process?
v. Volcanic plug: It is formed when lava Ans: As earth movements never cease, mountains
solidifies in the volcanic neck. e.g. Devil’s are created and eroded continuously over time.
Tower in USA.
vi. Cinder cone: During an eruption, solid 4. Try this. (Textbook pg. no 4)
material is ejected in large quantities, Observe the diagrams in fig. 1.5. Try to

nt
comprising ash, cinder, breccia, etc. It is understand the different types of fold shown in
deposited around the mouth until a conical the diagram and match it with its characteristics.
hill with steep slopes is formed. e.g. Write the name of the fold in the space given
Mt. Nuovo in Italy below.
vii. Composite cone: It is built of alternate

te
Ans: i. Symmetrical ii. Isoclinal
layers of lava and cinder. It is symmetrical in iii. Asymmetrical iv. Recumbent
shape. e.g. Mt. St. Helens in USA. v. Overturned
[Note: Students are expected to refer Q.6.(7) for
diagrams.] 5. Try this. (Textbook pg. no 5)

on
Observe the diagrams in fig. 1.6 and read the
Apply Your Knowledge
explanation regarding the characteristics of
various faults given below. Identify the faults and
1. Let’s recall. (Textbook pg. no 1) match each of them with their characteristics.
Observe the following pictures in fig. and
Ans: i. Normal ii. Reverse
discuss the questions in the class.
iii. Thrust iv. Tear
i. What might be the reasons behind buildings
C
collapsing in photo 1? 6. Think about it. (Textbook pg. no 6)
ii. Which event is depicted in photo 2? What i. When can faults form in fold mountains?
impact does it bring about in the ii. Can folds form in block mountains? Find the
surroundings? reasons and discuss.
iii. In photo 3, what could be the reason
Ans: i. Cracks may develop in the rocks of fold
e
behind the bend in the rock strata?
mountains due to tensional forces.
iv. What could be the reason behind the
ii. No, as block mountains are formed due to
difference in altitudes of the land and the
tensional forces and in rocks which are too
pl

steepness of the slope in photo 4?

rigid to fold.
v. Classify the events in the photos into
sudden and slow movements. 7. Let’s recall. (Textbook pg. no 6)
vi. Example of which of these movements is On 19th August, 2018, around 300 people died
m

not likely to be found in the mainland of the in Indonesia.

Indian sub-continent? Many buildings collapsed. Many roads broke
Ans: i. Earthquake apart. A tsunami was generated.
ii. Volcanic eruption i. What was the cause behind these events?
It causes destruction of life and property.
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ii. What actually happened during this natural

iii. Forces inside the earth’s surface. event?
iv. Perhaps a part of land subsided due to iii. Name the energy waves involved in this
cracks in the earth’s surface. natural event.
v. Sudden movements: Photos 1 and 2
iv. Observe the diagram in figure and label the
Slow movements: Photos 3 and 4 boxes.
vi. Volcanic eruptions
Ans: i. Earthquake
2. Think about it. (Textbook pg. no 3) ii. Due to tectonic movements, an earthquake
How will compressional forces affect brittle of magnitude 7.5 occurred with its
rocks? epicentre in the mountainous Donggala
Ans: Compressional forces would break brittle rocks Regency, Indonesia.
and no folding would occur. iii. Tsunami
11
 

Std. XI: Perfect Geography

iv. Ans: Refer Q.7.(4).
Epicentre
9. Think about it. (Textbook pg. no 7)
Earth’s Why has a shadow zone for L-waves not been
surface shown in fig.?
Ans: Refer Q.2.(4).

L-waves 10. Can you tell? (Textbook pg. no 7)

P-waves In fig. A, B, C are three points on the earth’s

nt
surface. Analyse their locations with respect to
Seismic focus S-waves epicentre and shadow zones.
Ans:

Point Location Shadow Zone

te
A within 105 from the Nil
epicentre
8. Think about it. (Textbook pg. no 6) B between 105 and 140 P-wave shadow
Look at fig. During an earthquake, do you think from the epicentre zone

on
the seismic waves reach entire portion of the C beyond 105 from the S-wave shadow
earth? Is there any region on the Earth’s surface epicentre zone
where a given earthquake will not be reported?
11. Give it a try. (Textbook pg. no 8)
How to locate epicentre of a given earthquake?
Take the given hypothetical data in the table.
C
The data shows the time of arrival of P-waves and S-waves at 3 seismograph stations.
Assume the scale of the map as 1 cm: 18 km.

Recording Station P-wave arrival time (IST) S-wave arrival time (IST)
Jalana 11: 06: 06 11: 06: 19
e
Washim 11: 06: 46 11: 07: 03
Aurangabad 11: 07: 06 11: 07: 24
pl

Ans: 1. The time difference between the arrival of P-waves and S-waves for each station –
Time lag = Arrival time of S-waves – Arrival time of P-waves
Jalna = 11:06:19  11:06:06 = 13 sec
Washim = 11:07:03  11:06:46 = 17 sec
m

Aurangabad = 11:07:24 – 11:07:06 = 18 sec

2. Actual distance on land surface for each station

Jalna = 13  8 = 104 km
Washim = 17  8 = 136 km
Sa

Aurangabad = 18  8 = 144 km

Actual distance
3. Jalna =
Scaleof the map
104
=
18
= 5.8 cm
136
Washim = = 7.6 cm
18
144
Aurangabad = = 8 cm
8

12
 

Chapter 1: Earth Movements

WASHIM
Jafrabad

Khultabad Lonar

JALANA
AURANGABAD HINGOLI
Gangapur Jintur

nt
Ambad
Nevasa Ghansawangi
Paithan
Takli Ambad PARBHANI
Shevgaon

te
Pathri
Gevrai
Mudgal
N
BEED

on
0 80 160

The place which is around 18 km far from south direction of Mudgal is the epicentre.
C
12. Seismic Zones in India (Textbook pg. no 9)
Zone Degree of risk States/UTs
I Least
II Low
III Moderate
e
IV High
V Very High
pl

Ans:
Zone Degree of risk States/ UTs
I Least Nil
II Low Telangana, Odisha, Chhattisgarh, Eastern Rajasthan
m

III Moderate Eastern Maharashtra, Madhya Pradesh, Tamil Nadu, Kerala, Jharkhand,
Western Rajasthan, Andhra Pradesh, Haryana
IV High Jammu, Himachal Pradesh, Sikkim, Punjab, Chandigarh, Uttar Pradesh, West
Bengal, Delhi, Western Maharashtra, Southern Bihar, Eastern Gujarat,
Lakshadweep islands
Sa

V Very High Kashmir, Northern Bihar, Uttarakhand, Meghalaya, Assam, Mizoram, Tripura,
Arunachal Pradesh, Nagaland, Manipur, Western Gujarat, Andaman and
Nicobar Islands
13. Find out! (Textbook pg. no 9)
Find out examples of active, dormant and extinct volcanoes.
Ans: i. Active volcanoes:
Mt. Fujiyama in Japan, Mt. Stromboli in Mediterranean Sea.
ii. Dormant volcanoes:
Mt. Vesuvius in Italy, Mt. Katmai in Alaska, Barren Island, India
iii. Extinct volcanoes:
Mt. Kilimanjaro in Tanzania.

13
 

Std. XI: Perfect Geography

Chapter Assessment
Time: 1.00 Hr. Total Marks: 20
Q.1. (A) Fill in the blanks with appropriate alternatives given below and rewrite the sentences. [3]
1. Deccan trap in India is an example of _______.
(A) block mountain (B) rift valley
(C) lava plateau (D) caldera
2. Orogenic movements are also known as _______ movements.

nt
(A) slow (B) sudden
(C) horizontal (D) vertical
3. Graben means _______.
(A) rift valley (B) block mountain

te
(C) fold Mountain (D) volcano
(B) Identify the incorrect factor. [2]
1. The different parts of fold are:
(A) Limb (B) Anticline
(C) Fracture (D) Syncline

on
2. The waves associated with earthquakes are:
(A) M-waves (B) P-waves
(C) S-waves (D) L-waves
Q.2. Give geographical reasons. (Any One) [3]
1. Extinct conical volcanoes often form crater lakes.
C
2. Soft rocks form folds while hard rocks form faults.
Q.3. Write short notes on. (Any One) [4]
1. Major belts of earthquakes and volcanoes
2. Classification of fold mountains depending on their age
e
Q.4. Answer in detail. (Any One) [8]
1. Write a note on volcanic materials.
2. Explain different types of folds.
pl

Answers
Q.1. (A) 1. (C) 2. (C) 3. (A)
(B) 1. (C) 2. (A)
m

Q.2. 1. i. At times, the eruption of volcano brings about a large quantity of material and relieves lot of
pressure.
ii. After a volcanic eruption, a large and deep depression called caldera may remain in that area. This
can be around 10 m wide and hundreds of metres deep.
Sa

iii. A smaller caldera is known as crater.

iv. When the funnel-shaped crater of an extinct volcano is filled with rain water, it forms a crater
lake.
2. i. Soft rocks, deep within the crust, are flexible and under high pressure.
ii. Hence, they fold easily due to compressional (converging) forces.
iii. Hard rocks, near the earth's surface, are rigid and not under high pressure.
iv. Hence, they form faults easily due to tensional forces.
Q.3. 1. The three major belts or zones of earthquake and volcanoes on the earth are as follows:
i. Circum-Pacific Belt: It is called the ‘Ring of Fire’. It includes the volcanoes of Eastern and Western
coastal areas of the Pacific Ocean. Cotopaxi, the highest volcanic mountain of the world, is found
in this belt.
14
 

Chapter 1: Earth Movements

ii. Mid-Atlantic Belt: It covers the Mid-Atlantic Ridge. The most active volcanic area is Iceland which
is found on Mid-Atlantic ridge.
iii. Mid-Continental Belt: It includes the volcanoes of Alpine mountains, Mediterranean Sea and the
Easter Africa fault zone. Stromboli and Etna, Italy are famous volcanoes.
2. i. Folding leads to development of fold mountains.
ii. Old fold mountains are over 200 million years of age. e.g. the Aravalli in India, the Urals in Russia
and the Appalachians in USA.
iii. Young fold mountains are between 10 to 25 million years of age. e.g. the Himalayas in India, the
Rockies in USA and the Andes in South America.

nt
Q.4. 1. i. Solid material: It consists of dust particles and rock fragments.
a. Volcanic dust: Very fine dust particles
b. Ash: Small-sized particles
c. Cinders: Half-burnt pieces of solid material

te
d. Breccia: Solid angular fragments
e. Volcanic bombs: Small fragments falling on the earth, formed when lava material solidify
when thrown into the air.
ii. Liquid material:

on
a. Magma: Molten rock material below the earth’s surface.
b. Lava: Molten rock material on the earth’s surface.
c. It is classified into acidic lava and basic lava based on the percentage of silica. Acidic lava
contains higher percentage of silica while basic lava contains less percentage of silica.
iii. Gaseous material:
a. During an eruption, a dark, cauliflower-shaped cloud is seen over the crater.
b. It comprises smoke and inflammable gases, which produce flames.
C
2. i. Asymmetrical: The axial plane is inclined. The limbs are inclined at different angles.
e
pl

ii. Isoclinal: The limbs slope in the same direction with same amount. The axial plane may be
vertical, inclined or horizontal. Slope of some portion of limbs is near vertical.
m
Sa

iii. Symmetrical: The axial plane is vertical. Limbs are inclined at same angle.

15
 

Std. XI: Perfect Geography

iv. Recumbent: Axial plane is almost horizontal. One limb lies over the other in horizontal direction.

nt
v. Overturned: One limb lies above the other limb. Limbs slope unequally in the same direction.

te
on
C
e
pl
m
Sa

16
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