Logarithmic Scale Earthquake Magnitude

Even though today s earthquake was estimated to be 2 5 times the magnitude of the actual earthquake the richter scale isn t the metric you want to use for the.

Logarithmic scale earthquake magnitude. The richter scale earthquakes are measured on the richter scale which is a base 10 logarithmic scale. 8 most magnitude scales are based on measurements of only part of an earthquake s seismic wave train and therefore are incomplete. A logarithmic scale or log scale is a way of displaying numerical data over a very wide range of values in a compact way typically the largest numbers in the data are hundreds or even thousands of times larger than the smallest numbers such a scale is nonlinear.

This was later revised and renamed the local magnitude scale denoted as ml or m l. Denoted explicitly with m w or mw and generally implied with use of a single m for magnitude is a measure of an earthquake s magnitude size or strength based on its seismic moment a measure of the work done by the earthquake it was defined in a 1979 paper by thomas c. This scale measures the magnitude of an earthquake which is the amount of energy released by it.

Magnitude is determined using the logarithm of the amplitude height of the largest seismic wave calibrated to a scale by a seismograph. The numbers 10 and 20 and 60 and 70 are not the same distance apart on a log scale. This corresponds to a ratio of intensities of 800 000 000 so the richter scale provides more manageable numbers to work with.

Richter studied many earthquakes that occurred between 1900 and 1950. Richter and presented in his landmark 1935 paper where he called it the magnitude scale. The richter scale also called the richter magnitude scale or richter s magnitude scale is a measure of the strength of earthquakes developed by charles f.

Because of various shortcomings of the m l scale most. For every single increase on this scale the magnitude is increased by a factor of 10. For example a magnitude 5 3 is a moderate earthquake and a 6 3 is a strong earthquake.

In fact the richter scale breaks down for very large seismic events and a newer calculation has become more standard. The largest had magnitude of 8 9 on the richter scale and the smallest had magnitude 0. All magnitude scales retain the logarithmic scale as devised by charles richter and are adjusted so the mid range approximately correlates with the original richter scale.

Visit howstuffworks to learn more. The moment magnitude scale and the wikipedia article. Richter and beno gutenberg.

Magnitude is expressed in whole numbers and decimal fractions. Sir in jude webber s article on the mexico earthquake mexican death toll hits 90 from massive earthquake september 10 she reports that quakes are measured on a scale of 0 to 10. The moment magnitude scale mms.