Essay On Magnitude Scale

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Introduction:
Living in Skopje, the capital city of a country that is subjected to many earthquakes, some stronger than others, made me interested in earthquakes and finding more about them.
The strongest earthquake Skopje has experienced throughout history that caused a severe destruction was the earthquake in 1963 measured at 6.9 on the Richter scale and 6.1 on the Magnitude Moment Scale, which killed over 1,000 people and destroyed 80% of the city.
This made me curious to look deeper into the difference between the two magnitude scales, which were brought into use a few decades apart.
This exploration will be comparing the two magnitude scales, The Richter Scale and the Moment Magnitude Scale, and I will look at the math used behind
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The Mercalli intensity scale:
Aside from the Richter and Moment Magnitude scales there is a third scale that is widely used as well, which is the Mercalli intensity scale. This scale unlike the other two scales, which are magnitude scales measuring the energy released by an earthquake, it measures the physical effects of an earthquake. This scale was modified in the 1890s by an Italian volcanologist, Giuseppe Mercalli, thus its name the Mercalli scale. The scale had been going through a few other modifications by different geophysicists and seismologists, which led to the name Modified Mercalli scale that is used nowadays. The scale ranges from 0 to XII and it is based on physical reports that the surrounding experienced or people felt. On the following picture 5 we can see how is the size of the earthquake determined through the physical experiences.
I. Instrumental
Not felt by many
II. Weak
Felt only by few people at higher floors in buildings; delicate objects may swing
III. Slight
Felt by some indoors again at higher floors; vibration similar to a passing truck
IV. Moderate
Indoors felt by many, outdoors by some
V. Rather Strong
Felt by most indoors and outdoors; objects may break; vibration similar to a passing

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