Magnitude of Earthquake


 
 
Concept Explanation
 

Magnitude of Earthquake

Magnitude of an Earthquake: The most common scale used to measure the magnitude of an earthquake is the Richter scale. An earthquake of magnitude 2.0-4.0 on the Richter scale is not too damaging. One of magnitude 4-8 is considered a moderate to severe earthquake. An earthquake of magnitude greater than 8-9 would be very severe.  On 26 January 2001, there was a major earthquake of magnitude 7.6-8.1 in Gujarat. Records of earthquakes

  • The very biggest earthquakes ever recorded have magnitudes in the range of 8.5-9.5. Earthquakes with magnitude greater than 7.5 are called "great", those in the range of 6.5-7.5 are"major", those between 5.5 and 6.5 are termed "large" and those of magnitudes 4.5-5.5 are"moderate". The rest are "small". Big earthquakes are less frequent than little ones. Each year more than a million earthquake happen. 
  • The earthquakes which was most destructive of human life was the Shansi Province, China, event of 1556 (magnitude unknown) which killed 830,000 people, although China came close to that again when 650,000 perished in the magnitude 7.6 Tangshan Province event of 1976. Out of the 9 earthquakes known to have killed more than 100,000 people, 6 occured in china, 2 in Japan and 1 in India.
  • MagnitudeEarthquake effect
    2.5 or lessUsually not felt, but can be recorded by seismograph.
    2.5 to 5.4Often felt, but only causes minor damage.
    5.5 to 6.0Slight damage to buildings and other structures.
    6.1 to 6.9May cause a lot of damage in very populated areas.
    7.0 to 7.9Major earthquake. Serious damage.
    8.0 or greaterGreat earthquake. Can totally destroy communities near the epicenter.
    Sample Questions
    (More Questions for each concept available in Login)
    Question : 1

    Earthquake at two places A and B were measured by a seismograph which recorded the magnitude as 2 and 4. The destructive energy at A and B can be compared as under :

    Right Option : C
    View Explanation
    Explanation
    Question : 2

    An earthquake of magnitude ___________ on the Richter scale is not too damaging

    Right Option : C
    View Explanation
    Explanation
    Question : 3

    An earthquake of magnitude 2.0 - 2.5 is:

    Right Option : B
    View Explanation
    Explanation
     
     


    Students / Parents Reviews [10]