Earthquakes: ICSE Class 9 Geography solutions

Summary

An earthquake is a tremor below the earth’s surface that causes the crust to shake. These tremors happen because of stresses that break the earth’s crust. Earthquakes are caused by strain in the crust from various factors. When the crust cannot handle the strain, energy is released suddenly as a violent shock. These shocks are seismic waves that spread from the earthquake’s origin, called the seismic focus.

The main causes of earthquakes include volcanoes. Volcanic eruptions push hot gases upwards, which violently push the earth’s crust, causing earthquakes. Earthquakes and volcanic activity are often linked. Plate tectonics is another major cause. The earth’s crust is made of moveable plates. When these plates move, slide past each other, or collide, faults are created, leading to earthquakes. These tectonic earthquakes are very common and strong. Folding and faulting, which are internal movements in the earth’s crust, also cause earthquakes by displacing rocks. Human activities like building large dams or nuclear explosions can also trigger earthquakes.

Earthquake vibrations travel as P-waves (Primary), S-waves (Secondary), and L-waves (Long or Surface waves). P-waves are fast and can travel through solids, liquids, and gases. S-waves arrive next and cannot pass through liquids. L-waves are the last to arrive and cause the most ground motion. The point on the surface directly above the seismic focus is the epicentre. Earthquakes are measured using a seismograph, the Richter Scale, and the Mercalli Scale. The Richter Scale measures the earthquake’s power from 1 to 9. Each point up represents a tenfold increase in wave strength.

Earthquakes have constructive effects, like releasing the earth’s stored energy and creating new landforms. However, their destructive effects are more widely known. These include the collapse of buildings, submergence of coastal areas, and changes in river courses. Earthquakes cause great danger to human life from falling structures or resulting landslides and floods. Fires can break out from broken gas pipes or damaged electrical wires. Undersea earthquakes can generate tsunamis, which are large, destructive ocean waves. The term “tsunami” comes from Japanese words meaning “harbour wave.” Flash floods can occur if dams are damaged or river flows are blocked by debris.

Most earthquakes happen along plate boundaries. The main earthquake zones are the Circum-Pacific Mountain Belt, which has 70% of all earthquakes. This area includes Japan and the Philippines and is known as the “Pacific Ring of Fire” because it is a zone with many volcanoes and earthquakes forming a ring-like shape around the Pacific Ocean. The Mid-world Mountain Belt, covering Europe and Asia, accounts for about 20% of earthquakes. The Mid-Atlantic Ridge experiences the remaining 10%. Predicting earthquakes accurately is still difficult, though scientists study seismic waves and changes in sea level or Earth’s magnetic field for clues.

Textbook solutions (Morning Star/Total)

Multiple-Choice Questions

1. A tremor below the surface of the earth which causes shaking of the crust:

(a) Earthquake waves
(b) Earthquake
(c) Seismic waves
(d) None of the above

Answer: (b) Earthquake

2. A series of shocks that result from sudden earth movement:

(a) Earthquake
(b) Volcanoes
(c) Earthquake waves
(d) Plate tectonics

Answer: (c) Earthquake waves

3. Which amongst the following is NOT a factor that causes an earthquake?

(a) Folding and faulting
(b) Volcanoes
(c) Lava
(d) Plate tectonics

Answer: (c) Lava

4. Which waves are recorded on a seismograph after the P waves?

(a) Primary waves
(b) Push waves
(c) Shear waves
(d) Surface waves

Answer: (c) Shear waves

5. Which of the following measures the power of an earthquake on a scale of 1 to 9?

(a) Seismograph
(b) Richter scale
(c) Mercalli scale
(d) Thermometer

Answer: (b) Richter scale

6. The point on the earth’s surface directly above the seismic focus is called:

(a) Epicentre
(b) Seismic focus
(c) Seismograph
(d) Mercalli

Answer: (a) Epicentre

7. The instrument that grades the earthquakes on the basis of observed effects on a 12-point scale.

(a) Thermometer
(b) Seismograph
(c) Richter scale
(d) Mercalli scale

Answer: (d) Mercalli scale

8. Which, amongst the following, is NOT a destructive effect of earthquakes?

(a) Submergence
(b) Landslides
(c) Energy release
(d) Tsunami

Answer: (c) Energy release

9. A large destructive ocean wave that can be generated by any disturbance (earthquakes, volcanoes etc.) that rapidly displaces a large mass of water:

(a) Submergence
(b) Tsunami
(c) Landform
(d) Volcano

Answer: (b) Tsunami

10. Which of the following is not correct?

(a) Circum Pacific Mountain Belt : 70% of world earthquakes
(b) Mid Atlantic Ridge : 10% of world earthquakes
(c) Mid-world Mountain Belt : 20% of world earthquakes
(d) Pacific Ring of Fire : 15% of world earthquakes

Answer: (d) Pacific Ring of Fire : 15% of world earthquakes

Short Answer Questions

1. What is called an earthquake? Give one recent example of an earthquake.

Answer: An earthquake is defined as a tremor below the surface of the earth which causes shaking of the crust. A recent example of an earthquake is the one that occurred in Turkey in 2023, which had a magnitude of 7.8.

2. State two natural causes of an earthquake.

Answer: Two natural causes of earthquakes are:

(i) Volcanoes: Volcanic eruptions are one of the main causes of earthquakes. During the volcanic eruptions, hot gases are pushed upward and they push violently the earth’s crust surface upward causing earthquakes.
(ii) Plate Tectonics: According to the plate tectonic theory, the crust of the earth is made of a series of moveable plates. These plates move and slide over each other. Most earthquakes occur on account of plate movements. When two plates slip past each other or collide against each other, their edges produce faults along the lines of weakness.

3. Name two man-made causes of an earthquake. Give one example.

Answer: Two man-made causes of earthquakes include the construction of huge dams and nuclear explosions. For example, the Koyna earthquake in Maharashtra was caused by the construction of the Koyna dam in a seismically active region.

4. What are known as seismic focus and epicentre with respect to an earthquake?

Answer: With respect to an earthquake, the point of origin of the seismic waves is called the Seismic focus. The point on the earth’s surface directly above the seismic focus is called the epicentre.

5. What is known as Richter scale? State its uses.

Answer: The Richter scale is an instrument that measures the power of an earthquake on a scale of 1 to 9. It is used for measuring the intensity, or the amount of energy released during an earthquake, and it measures the absolute intensity with mathematical precision.

6. How are earthquakes useful?

Answer: Earthquakes are useful in the following ways:

Energy release: Earthquakes help the earth release its stored up energy. The majority of the earthquakes occur around the plate margins. This energy release helps to keep the earth in good shape.
Landforms: On account of both vertical and lateral displacement of the earth’s crust, earthquakes may raise or lower parts of earth especially near the seashore. For example, Sagami Bay of Japan was uplifted 200 m in 1923. Landslides triggered by earthquakes cause formation of lakes as has happened at many places in the Himalayan region.

7. Give any two destructive effects of earthquakes.

Answer: Two destructive effects of earthquakes are:

Collapse of structures: Human beings have settlements in active earthquake zones. Often these houses and other structures collapse causing great loss of property. For example, the destruction caused by a tsunami.
Submergence: The forces of uplift and subsidence also cause submergence of coastal parts. For example: Dwarka in Gujarat which now lies submerged under the sea.

8. What is a tsunami? Give one recent example of a place struck by a tsunami.

Answer: A tsunami is a large destructive ocean wave that can be generated by any disturbance that rapidly displaces a large mass of water, such as an earthquake, volcanic eruption, landslide or meteorite impact. However, the most common cause is an undersea earthquake. The name ‘tsunami’ is from the Japanese words: ‘Tsu’ and ‘nami’ meaning ‘harbour’ and ‘wave’ respectively. So tsunamis are harbour waves.

A recent example of a place struck by a tsunami is Java and Sumatra in Indonesia, where a tsunami on December 22, 2018, resulted in more than 300 deaths.

9. How do Japanese predict earthquakes?

Answer: The Japanese use the methods of measuring changes in sea level and variations in Earth’s magnetic field to predict earthquakes.

10. Name the two belts where most of the earthquakes occur.

Answer: The two belts where most of the earthquakes occur are The Circum Pacific Mountain Belt, which has 70% of all earthquakes, and The Mid-world Mountain Belt, where about 20% of all earthquakes occur.

Structured Questions

1. (a) Describe how earthquakes are caused on the surface of the earth.

Answer: An earthquake is defined as a tremor below the surface of the earth which causes shaking of the crust. These devastating tremors are caused by the stresses that break the earth’s crust. Earthquakes are caused by the strain in the earth’s crust which in turn is a result of a number of factors. When the earth’s crust is unable to accommodate itself to the strain, it results in a sudden release of tremendous energy in the form of a sudden violent shock.

A series of shocks that result from sudden earth movement, e.g. along a fault, are known as earthquake (seismic) waves. The main factors that cause earthquakes include volcanoes, where hot gases are pushed upward violently pushing the earth’s crust surface upward; plate tectonics, where the movement and sliding of moveable plates past or against each other produce faults; folding and faulting due to internal horizontal and vertical movements causing displacement of rocks; and man-made causes like construction of huge dams or nuclear explosions near fault zones.

(b) What is the difference between seismic focus and epicentre?

Answer: The seismic focus is the point of origin of seismic waves, which are the waves generated by an earthquake. The epicentre is the point on the earth’s surface directly above the seismic focus.

(c) Give a geographical reason for each of the following:
(i) Most earthquakes occur on account of plate movements.

Answer: Most earthquakes occur on account of plate movements because the crust of the earth is made of a series of moveable plates. These plates move and slide over each other. When two plates slip past each other or collide against each other, their edges produce faults along the lines of weakness. In areas of the world that lie along the edges of lithospheric plates, earthquakes are common. Most earthquakes originate from plate boundaries.

(ii) Primary waves are the first earthquake waves to be recorded on a seismogram.

Answer: P (primary or push) waves are the first earthquake waves to be recorded on a seismogram of an earthquake.

(iii) Volcanic activity and earthquakes occur in the same belt.

Answer: Volcanic activity and earthquakes occur in the same belt because volcanic activities and seismic occurrences (earthquakes) are interrelated. An earthquake often follows a volcanic eruption, and a volcanic eruption can follow an earthquake. Both phenomena are common in areas along the edges of lithospheric plates, such as the Circum Pacific Mountain Belt, where plate movements cause both earthquakes and create conditions for volcanic eruptions. For instance, Indonesia, located on the Pacific Ring of Fire, has thousands of volcanic islands created over time as plates shifted and molten magma exerted pressure, and this region is also prone to severe earthquakes.

(d) Explain the three types of earthquake waves.

Answer: The vibrations from an earthquake travel in three types of waves: P-Primary waves, S-Secondary (or Shear waves) and L-Long waves (or Surface waves).

(i) P (primary or push) waves are the first earthquake waves to be recorded on a seismogram of an earthquake. They are compressional, i.e., the particles vibrate in the direction of movement of the wave, similar to a sound wave. They can pass through solids, liquids and gases.
(ii) S (secondary or shear) waves are recorded on a seismogram after the P waves. They are distortional waves in which the particles vibrate at right angles to the direction of movement of the wave. S-waves travel through the earth’s interior but cannot be transmitted by liquids.
(iii) L (surface or long) waves travel along the surface of the earth and are recorded after the P and S waves. Two types of L waves are identified: Love waves and Rayleigh waves. The P-waves and S-waves travel through the interior of the earth. The surface waves (or L-waves) are the last to arrive. It is these waves that make the inhabitants of the earth feel the ground motion.

2. (a) The destructive effects of an earthquake are far more than its constructive effects. Give reasons to support your answer.

Answer: From a human point of view, earthquakes are regarded as destructive, causing loss to property and life, and these destructive effects are often far more significant than their constructive effects.

Constructive effects include energy release, where earthquakes help the earth release its stored-up energy, which helps to keep the earth in good shape, and the formation of landforms, as earthquakes may raise or lower parts of the earth, especially near the seashore, and landslides triggered by earthquakes can cause the formation of lakes.

However, the destructive effects are numerous and severe:

Collapse of structures: Houses and other structures collapse, causing great loss of property, as seen in tsunamis.
Submergence: Forces of uplift and subsidence can cause submergence of coastal parts, like Dwarka in Gujarat.
Course of Rivers: Earthquakes can change the course of rivers, rendering areas unsuitable for irrigation and agriculture.
Danger to human life: Severe earthquakes kill many people due to house collapse, falling structures, landslides, and floods.
Landslides: Shockwaves destabilise loose rocks, leading to landslides that damage buildings and transport systems, especially in regions like the Himalayas, Alps, and Andes.
Fires: Earthquakes can cause fires from inflammable material, broken gas pipes, bursting gas cylinders, damaged oil refineries, and live electric wires.
Tsunami: Undersea earthquakes can generate large destructive ocean waves that displace a large mass of water, causing widespread devastation.
Flash Floods: Strong shock waves can damage dams and embankments, causing stored water to spread speedily. Debris can block river flow, diverting it and causing flash floods, damage to life, and property.

(b) How is the intensity of an earthquake measured?

Answer: The intensity, or the amount of energy released during an earthquake, is measured using instruments like the Richter Scale and the Mercalli scale. The Richter scale measures the power of an earthquake on a scale of 1 to 9 and measures the absolute intensity with mathematical precision; it is the most commonly used. The Mercalli scale grades earthquakes on the basis of observed effects on a 12-point scale. The severity of earthquakes is generally measured on the Richter scale.

(c) Is it possible to predict an earthquake? Give reasons to support your answer.

Answer: Earthquake prediction is a respectable scientific pursuit. The Russians were the first to discover P and S seismic waves in the 1960s, on the basis of which predictions were made, and these waves are still the only means available to seismologists to predict earthquakes. The theory of Plate Tectonics offers another means of prediction on scientific lines. For example, Japanese use methods of measuring changes in sea level and variations in Earth’s magnetic field to predict earthquakes. However, no method is still foolproof, as has been proved by recent earthquakes in Japan, India, and the USA.

(d) How are earthquakes distributed over the globe?

Answer: Earthquakes are not randomly distributed over the globe; most earthquakes originate from plate boundaries. In areas of the world that lie along the edges of lithospheric plates, earthquakes are common. The main earthquake belts of the world are:

(i) The Circum Pacific Mountain Belt: This belt has 70% of all earthquakes. A part of the San Andreas Fault in the USA lies in this belt, making California highly prone to earthquakes. The areas of Japan, the Philippines, and Indonesia all form parts of this belt and are prone to severe earthquakes.
(ii) The Mid-world Mountain Belt: This belt stretches from Eastern Europe covering Alpine-Himalayan ranges in Europe and Asia. About 20% of all earthquakes occur in this zone.
(iii) The Mid-Atlantic Ridge: This belt comprises areas along the mid-oceanic ridges as well as many islands near the ridges of the Atlantic Ocean. The remaining 10% of earthquakes occur in this belt. In this ridge, two tectonic plates move in opposite directions, and some moderate earthquakes are recorded along the ridge. The Rift Valley of East Africa is considered an extension of this belt.

Thinking Skills

1. Prevention is better than cure.’ How does this statement apply to earthquakes? Give reasons to support your answer.

Answer: Prevention is better than cure. This saying fits very well when it comes to earthquakes. Earthquakes strike without warning, and once they do, the destruction they leave behind can be enormous—loss of lives, homes, and infrastructure. That’s why it’s much better to prepare in advance. For instance, building earthquake-resistant structures, avoiding construction in high-risk zones, and following proper planning laws can save many lives. Public awareness and regular earthquake drills can also make people more alert and ready. Since earthquakes cannot be prevented or precisely predicted, taking preventive steps is the best way to reduce their impact.

2. Imagine you were sitting in the balcony of a seaside resort, when you suddenly noticed waves rising high in the sky. Suddenly there was a surge in the height of the waves and they turned into a tsunami. What could have caused this tsunami and what were its consequences.

Answer: If I were sitting on a balcony in a seaside resort and suddenly noticed huge waves rising abnormally high, it would most likely be a tsunami. Such a massive surge in waves can happen when an undersea earthquake suddenly displaces a large volume of water. This could also happen due to a volcanic eruption or an underwater landslide. The results can be devastating. The tsunami waves can crash onto the shore with great force, flooding coastal areas, destroying buildings, and sweeping away people, vehicles, and animals. It often causes widespread panic, injuries, and loss of life, along with long-term damage to property and the environment.

Map Work/Project

1. Make a record of recent earthquakes in India. Find out the damage caused.

Answer: Do it yourself. Here are the instructions:

Step 1: Collect Information
- Visit reliable news websites such as NDTV, The Hindu, or Times of India.
- Use search terms like “recent earthquakes in India 2024” or “earthquake damage in India 2025”.
- For each earthquake, note the date, location, magnitude (Richter scale), and damage caused (e.g. buildings damaged, people injured, roads affected).
Step 2: Create a Table
Prepare a table in your notebook or project file with the following columns: DateLocationMagnitudeDamage CausedApril 15, 2025Assam5.4Cracks in buildings, minor injuriesJanuary 22, 2024Gujarat4.9No major damage, tremors felt Include three to five such entries.
Step 3: Optional Visuals
- If available, paste printed pictures of damaged areas or draw simple sketches showing earthquake effects.

2. On an outline map of the world show the world distribution of earthquakes. Mark earthquake prone areas in India.

Answer: Do it yourself. Here are the instructions:

Step 1: Get a World Map
- Use a blank outline map of the world. You can download and print one or draw a basic version by hand.
Step 2: Mark Major Earthquake Belts
- Shade or mark the following earthquake zones:
  - Circum-Pacific Belt (around the Pacific Ocean – includes Japan, Philippines, west coast of North and South America).
  - Mid-World Mountain Belt (from Southern Europe through the Himalayas and into Southeast Asia).
  - Mid-Atlantic Ridge (central part of the Atlantic Ocean).
Step 3: Highlight Earthquake Prone Areas in India
- Mark these regions:
  - Jammu and Kashmir
  - Himachal Pradesh
  - Uttarakhand
  - Northeastern states (Assam, Manipur, etc.)
  - Gujarat
  - Bihar
  - Andaman and Nicobar Islands
Step 4: Add a Legend
- Create a small box explaining your symbols or colours, such as:
  - Red: Global earthquake zones
  - Blue: Indian earthquake zones

Extras

Additional MCQs

1. What is an earthquake?

A. Tremor below surface
B. Volcanic eruption
C. Fault movement
D. Ocean wave

Answer: A. Tremor below surface

2. What triggers an earthquake?

A. Sudden energy release
B. Gradual sedimentation
C. Erosion
D. Tidal forces

Answer: A. Sudden energy release

3. Which natural event can cause an earthquake?

A. Volcanic eruption
B. Flood
C. Tsunami
D. Monsoon

Answer: A. Volcanic eruption

4. Which process describes earthquakes due to slipping plates?

A. Plate tectonics
B. Folding
C. Weathering
D. Sedimentation

Answer: A. Plate tectonics

5. Which tectonic action involves compressional forces causing earthquakes?

A. Folding
B. Erosion
C. Subsidence
D. Sedimentation

Answer: A. Folding

6. Which human activity has been known to induce earthquakes?

A. Dam construction
B. Farming
C. Road paving
D. Deforestation

Answer: A. Dam construction

7. The Koyna earthquake in Maharashtra was linked to which dam?

A. Koyna
B. Bhakra
C. Hirakud
D. Tehri

Answer: A. Koyna

8. Which plate lowered below another causing the 2001 Gujarat earthquake?

A. Indian plate
B. Asiatic plate
C. Arabian plate
D. Nazca plate

Answer: A. Indian plate

9. Which scale measures earthquake magnitude with mathematical precision?

A. Richter scale
B. Mercalli scale
C. Beaufort scale
D. Fujita scale

Answer: A. Richter scale

10. Which scale grades earthquakes based on observed effects?

A. Mercalli scale
B. Richter scale
C. Beaufort scale
D. Mohs scale

Answer: A. Mercalli scale

11. Each whole-number increase on the Richter scale represents what change in wave amplitude?

A. Tenfold
B. Twofold
C. Hundredfold
D. Fivefold

Answer: A. Tenfold

12. The Assam earthquake of 1897 measured what on the Richter scale?

A. 8.7
B. 7.7
C. 7.8
D. 6.3

Answer: A. 8.7

13. What was the magnitude of the Gujarat earthquake in 2001?

A. 7.7
B. 8.7
C. 7.3
D. 9.1

Answer: A. 7.7

14. On which date did the Nepal earthquake of 2015 occur?

A. April 25, 2015
B. May 12, 2015
C. March 25, 2015
D. June 12, 2015

Answer: A. April 25, 2015

15. When did a major aftershock of magnitude 7.3 hit Nepal in 2015?

A. May 12, 2015
B. April 25, 2015
C. May 25, 2015
D. June 12, 2015

Answer: A. May 12, 2015

16. What is a tsunami?

A. Large ocean wave
B. Crust tremor
C. Rockslide
D. Seismic gas

Answer: A. Large ocean wave

17. The word tsunami comes from Japanese words meaning what?

A. Harbour wave
B. Storm surge
C. Sea quake
D. Water rise

Answer: A. Harbour wave

18. About 70% of global earthquakes occur in which zone?

A. Circum Pacific
B. Mid-Atlantic Ridge
C. Mid-world
D. East African Rift

Answer: A. Circum Pacific

19. Approximately 20% of earthquakes occur in which belt?

A. Mid-world
B. Circum Pacific
C. Mid-Atlantic Ridge
D. East African Rift

Answer: A. Mid-world

20. The remaining 10% of earthquakes mostly occur along which feature?

A. Mid-Atlantic Ridge
B. Circum Pacific
C. Alpine-Himalayan
D. San Andreas

Answer: A. Mid-Atlantic Ridge

21. Which instrument records seismic waves on paper?

A. Seismograph
B. Barometer
C. Hygrometer
D. Thermometer

Answer: A. Seismograph

22. What component of a seismograph records ground motions?

A. Pen
B. Drum
C. Spring
D. Magnet

Answer: A. Pen

23. Which waves are the first to be recorded on a seismogram?

A. P waves
B. S waves
C. L waves
D. T waves

Answer: A. P waves

24. Which waves vibrate in the direction of movement similar to sound waves?

A. P waves
B. S waves
C. L waves
D. Love waves

Answer: A. P waves

25. Which waves vibrate at right angles to wave movement?

A. S waves
B. P waves
C. L waves
D. Rayleigh waves

Answer: A. S waves

26. Which waves travel along Earth’s surface?

A. L waves
B. S waves
C. P waves
D. T waves

Answer: A. L waves

27. Which waves cannot pass through liquids?

A. S waves
B. P waves
C. L waves
D. Love waves

Answer: A. S waves

28. What is the point on the Earth’s surface directly above the seismic focus called?

A. Epicentre
B. Hypocentre
C. Fault
D. Ridge

Answer: A. Epicentre

29. What term describes the origin of seismic waves within Earth?

A. Seismic focus
B. Epicentre
C. Lithosphere
D. Fault line

Answer: A. Seismic focus

30. The 1906 earthquake of magnitude 8.3 occurred along which fault?

A. San Andreas
B. Himalayan
C. New Madrid
D. Great Rift

Answer: A. San Andreas

31. The eruption of which volcano triggered a deadly earthquake and tsunami?

A. Krakatoa
B. Vesuvius
C. Mauna Loa
D. Tambora

Answer: A. Krakatoa

32. Which bay in Japan was uplifted about 200 m by a 1923 earthquake?

A. Sagami Bay
B. Tokyo Bay
C. Osaka Bay
D. Hiroshima Bay

Answer: A. Sagami Bay

33. What phenomenon involves rapid flooding due to dam failure after an earthquake?

A. Flash floods
B. Tsunami
C. Landslide
D. Aftershock

Answer: A. Flash floods

34. What landforms can be created by landslides triggered by earthquakes?

A. Lakes
B. Mountains
C. Canyons
D. Plateaus

Answer: A. Lakes

35. What term describes a bend in layered rocks?

A. Fold
B. Fault
C. Ridge
D. Trench

Answer: A. Fold

36. What is a fracture with block movement in Earth’s crust called?

A. Fault
B. Fold
C. Ridge
D. Tilt

Answer: A. Fault

37. What is the flat surface along which slip occurs during an earthquake?

A. Fault plane
B. Seismic focus
C. Epicentre
D. Lithosphere

Answer: A. Fault plane

38. What adjective pertains to earthquakes?

A. Seismic
B. Volcanic
C. Tectonic
D. Hydrothermal

Answer: A. Seismic

39. Which term describes ripples and storms in oceans caused by oceanic earthquakes?

A. Tsunamis
B. Tides
C. Currents
D. Surges

Answer: A. Tsunamis

40. Which 1556 earthquake resulted in about 830,000 deaths?

A. Shansi China
B. Tangshan China
C. Gansu China
D. Izmit Turkey

Answer: A. Shansi China

41. Which 1976 earthquake caused approximately 255,000 deaths?

A. Tangshan
B. Gansu
C. Gujarat
D. Kwanto

Answer: A. Tangshan

42. Which 1737 earthquake in India led to 300,000 deaths?

A. Kolkata
B. Gujarat
C. Bhuj
D. Assam

Answer: A. Kolkata

43. The 2004 Indian Ocean earthquake had what magnitude?

A. 9.1
B. 7.7
C. 8.7
D. 7.6

Answer: A. 9.1

44. Approximately how many people died in the December 26, 2004 tsunami?

A. 275,000
B. 168,000
C. 200,000
D. 300,000

Answer: A. 275,000

45. Where did the magnitude 9.0 earthquake in 2011 occur?

A. Honshu Japan
B. Gansu China
C. Tangshan China
D. Izmit Turkey

Answer: A. Honshu Japan

46. Roughly how many deaths resulted from the April 25, 2015 Nepal earthquake?

A. 8,000
B. 21,000
C. 18,000
D. 30,000

Answer: A. 8,000

47. A tsunami struck Java and Sumatra causing over 300 deaths on which date?

A. December 22, 2018
B. December 26, 2004
C. April 25, 2015
D. May 12, 2015

Answer: A. December 22, 2018

48. Who first used seismic waves to make earthquake predictions?

A. Russians
B. Japanese
C. Americans
D. Indians

Answer: A. Russians

49. Which method do Japanese use to predict earthquakes?

A. Sea level changes
B. Satellite imaging
C. Solar flares
D. Rock sampling

Answer: A. Sea level changes

50. Which earthquake waves are recorded last on a seismogram?

A. L waves
B. S waves
C. P waves
D. T waves

Answer: A. L waves

Additional Assertion and Reason

1. Assertion (A): An earthquake is defined as a tremor below the surface of the earth which causes shaking of the crust.
Reason (R): These devastating tremors are caused by the stresses that break the earth’s crust.