A short and detailed comparison between Meracalli Scale and Richter Scale.

1. Mercalli Scale vs. Richter
Scale
NASIRAHMAD
National Centre of Excellence in Geology(NCEG),
University of Peshawar,
Pakistan

2. Mercalli Scale
• A scale of earthquake intensity ranging from I for an earthquake
detected only by seismographs to XII for one causing total
destruction of all buildings.
• Mercalli scale describes the intensity of an earthquake based on
its observed effects.
• The two scales have different applications and measurement
techniques.The Mercalli scale is linear and a descriptive scale.

3. History
• The Mercalli Intensity Scale was developed by Italian
volcanologist Giuseppe Mercalli in 1884 and expanded to
include 12 degrees of intensity in 1902 by Adolfo Cancani.
• It was modified again by HarryO.Wood and Frank
Neumann in 1931. It is known today as the Modified
Mercalli Intensity Scale.

4. Richter Scale
• Richter scale describes the earthquake's magnitude by
measuring the seismic waves that cause the earthquake.
• Richter scale is logarithmic. i.e. a magnitude 5 earthquake
is ten times as intense as a magnitude 4 earthquake.

5. History
• The Richter Magnitude Scale was developed in 1935 by Charles
Richter.
• It was initially created to study a particular area in California,
using the Wood-Anderson torsion seismograph, to compare
the size of different earthquakes in the region. He later
adapted the scale so that it could measure the size of
earthquakes around the globe.

6. Wood-AndersonTorsion Seismograph

7. Comparison chart

8. Measurement
• The Mercalli Intensity Scale measures the intensity of an
earthquake by observing its effect on people, the
environment and the earth’s surface.
• The Richter Scale measures the energy released by an
earthquake using a seismograph. A base-10 logarithmic
scale is obtained by calculating the logarithm of the
amplitude of waves recorded by the seismograph.

9. Comparing the Scales

10. Applications and Use
• The Mercalli Intensity Scale is only useful for measuring
earthquakes in inhabited areas and is not considered
particularly scientific, as the experiences of witnesses
may vary and the damage caused may not accurately
reflect an earthquake’s strength.
• It is, however, used to compare the damage caused by
earthquakes in different areas.

11. Applications and Use
• The Richter scale is used to measure the magnitude of
most modern earthquakes.
• It allows scientists to accurately compare the strength of
earthquakes at different times and locations.

12. END & GOODLUCK