# Moment Magnitude Scale

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When we see the news we always see some different types of natural disaster happens in neighboring countries or our country. One of the famous natural disaster is an earthquake. In the media, news reporter says the earthquake’s magnitude is scale 6. But, do we really know how much is scale 6 is influencing?. To tell the truth, We do not really know the true process behind measuring the earthquake and know how serious is the earthquake is. Measuring earthquake is important, because we can research more about strength of earthquakes happen in city, so researchers can bring out solutions to prevent huge casualties from next earthquake. There are 2 different types of measuring magnitude of earthquake. These methods are richter scale, The moment…show more content…
But it measures physical property of earthquake. Moment magnitude scale also use common logarithm with different equation (Image 4). The formula of the scale is Mw = 2/3 log10(M0) – 10.7. Where Mw represents power of earthquake in mechanical work. The value from the formula is alike with richter scale from magnitude of 3 to 7. Moment magnitude scale was developed in 1979 to solve problems that richter scale have. Newly developed moment magnitude scale doesn’t have any distance limit like richter scale has. Moment magnitude scale also have scale from one to ten. Moment magnitude scale can express the magnitude accurately over the scale of 7. However, moment magnitude scale cannot specifically show the details of earthquake when the magnitude of earthquake is below 3.5. Recently, scientists favor moment magnitude scale than richter scale for these reasons. More accuracy and no limits help them to study deeply about earthquakes. While two previous scales are measuring magnitude during the earthquake, Modified Mercalli scale (Image 5) measures intensity of earthquake after the earthquake. Modified Mercalli scale have total twelve different levels of scale. Each scale is diversified as how much people felt or man-made buildings are damaged. The information is gathered by survey from the people in the area the earthquake happened. Information is different by how far…show more content…
For big earthquakes, measuring the magnitude of earthquake using moment magnitude scale is good because of many advantages that richter scale do not have. the moderate range (3~7) value is similar between richter scale and moment magnitude scale. So it doesn’t really matter for what scale we should use. However, for the magnitude smaller than 3, richter scale is compatible for it. Moment magnitude scale can effectively use to measure bigger size of earthquake and moderate size. Modified mercalli Scale can tell more about making solutions for the earthquakes rather than looking the size like richter and moment magnitude scale. Modified mercalli scale is measuring the intensity of earthquake by people so researchers can determine the damage of earthquake and can bring solutions to prevent the huge