This set of Earthquake Engineering Multiple Choice Questions & Answers (MCQs) focuses on “Types of Earthquake”.
1. Which of these earthquakes occur within a plate?
a) Interplate earthquake
b) Intraplate earthquake
c) Interfault earthquake
d) Intrafault earthquake
View Answer
Explanation: Intraplate earthquakes are the earthquakes that occur inside a tectonic plate. Stresses within a plate result in this type of earthquakes. About 5% of the earthquakes occur within a plate. Gujarat earthquake which occurred in 2001 is an example of intraplate earthquake.
2. What is the range of depth of focus for a deep focus earthquake?
a) 0 km to 250 km
b) 100 km to 450 km
c) 300 km to 700 km
d) 70 km to 300 km
View Answer
Explanation: Deep focus earthquakes are the earthquakes having depth of focus in the range of 300 km to 700 km. These earthquakes begin where one plate moves under the other. They are of higher magnitudes, of range 6 to 8 or more. They are measured using Moment Magnitude scale.
3. Which type of earthquakes are of superior concern for earthquake resistant design of a structure?
a) Shallow focus earthquakes
b) Deep focus earthquakes
c) Volcanic earthquakes
d) Intermediate focus earthquakes
View Answer
Explanation: Shallow focus earthquakes are of superior concern for earthquake resistant design as the depth of focus is less than 70 km. These earthquakes are usually of large spread and cause greater damage at the surface. Closely 80% of the overall earthquakes are shallow focus earthquake.
4. Magnitude is a quantitative measure of the size of an earthquake.
a) True
b) False
View Answer
Explanation: Magnitude of an earthquake is a quantitative measure of the actual strength or size of an earthquake. It denotes the amount of energy released at the source of an earthquake. It is based on measurement of the maximum motion recorded by a seismograph. The two most important magnitude scales are Richter scale and Moment magnitude scale.
5. Which of the following seismic intensity scale is used in India?
a) Modified Mercalli (MMI) Scale
b) Medvedev-Sponheuer-Karnik (MSK) Scale
c) European Macroseismic Scale (EMS)
d) PHIVOLCS Earthquake Intensity Scale (PEIS)
View Answer
Explanation: The Indian Standard code, IS 1893 refers to the MSK scale of seismic intensity. MSK scale was developed for the eastern and central European states and is widely used in many Asian countries including India.
6. Which of the following Mercalli intensity scale is characterized by railway lines getting bent and landslides on steep slopes?
a) Disastrous
b) Catastrophic
c) Destructive
d) Strong
View Answer
Explanation: The Mercalli intensity X is termed as Disastrous. It is characterized by severe cracking of grounds, landslides on steep slopes, railway lines getting bent, many buildings getting destroyed, etc.
7. Rayleigh wave is used to describe which of the following magnitudes?
a) Local magnitude
b) Surface wave magnitude
c) Body wave magnitude
d) Duration magnitude
View Answer
Explanation: Rayleigh wave of 80 km wavelength and period of about 20 seconds is used to define the Surface wave magnitude. It is valid for an aperture greater than 15o, which is approximately 1650 km distance. The body wave magnitude is defined as the peak amplitude of P-wave group for 1 second period and wavelength less than 10 km.
8. What is the ratio of shaking amplitude of an earthquake that measures 5 on Richter scale to that of an earthquake measuring 4 on Richter scale?
a) 100
b) 10
c) 1
d) 0.1
View Answer
Explanation: A Richter scale is a logarithmic scale. An earthquake of magnitude 5 on Richter scale causes 10 times the ground movement caused by an earthquake of magnitude 4 on Richter scale. Therefore, the ratio is 10.
9. Who gave the approximate relationship between the intensity sustained in the epicenter and local magnitude of an earthquake?
a) Esteva and Rasenblueth
b) Hopkins and Timoshenko
c) Gutenberg and Richter
d) Bernoulli and Euler
View Answer
Explanation: The approximate relationship between the intensity sustained in the epicenter and local magnitude of an earthquake was given by Gutenberg and Richter in 1956. Esteva and Rasenblueth gave the correlation between magnitude, intensity and a short epicentral distance.
10. The effects of which of the following Mercalli intensity scales can only be detected by seismographs?
a) Moderate
b) Slight
c) Feeble
d) Instrumental
View Answer
Explanation: The first Mercalli intensity is termed as Instrumental. It cannot be noticed by people. It can be detected only by seismographs. Feeble intensity can be noticed only by sensitive people. Slight intensity can be felt by people at rest, especially on the upper floors. Moderate intensity is felt by people when they walk and loose objects start shaking.
Sanfoundry Global Education & Learning Series – Earthquake Engineering.
To practice all areas of Earthquake Engineering, here is complete set of Multiple Choice Questions and Answers.
