Although the curve of Earthquake Waves is recorded at Seismograph, the intensity and magnitude of the Earthquakes are measured by two different scales namely Richter Scale and Mercalli Scale.
- This scale, developed by Charles Richter, measures the magnitude of the energy released during the Earthquake.
- This scale is open-ended i.e. there is not any end of the scale but, it has never measured any Earthquake of magnitude greater than 8.9.
- The Richter-scale, in nature, is logarithmic based on 10.
That is, the Earthquake at magnitude 5 is 10 times more powerful than the Earthquake at magnitude 4 and 100 times more than the earthquake at magnitude 3.
The Mercalli Intensity Scale, developed by Giuseppe Mercalli, and expanded to include 12 degrees of intensity by Adolfo Can It was further modified again by Harry O. Wood and Frank Neumann and today known as Modified Mercalli Intensity Scale.
It measures the intensity of an earthquake based on its actual impacts on people, the environment and the Earth’s surface.
It is a closed-ended linear Scale, scaled from 1-12 or I-XII with zero effect in Intensity 1 Earthquake and total destruction in Intensity 12 Earthquake.