Date post: | 14-Apr-2017 |
Category: |
Education |
Upload: | anju-soman |
View: | 271 times |
Download: | 1 times |
Mathematics
Mathematics in Calculating The
Magnitude of an Earthquake
- Anju SomanRoll no. 90
A sudden violent shaking of the ground, typically causing great
destruction, as a result of movements within the earth's
crust or volcanic action.
What is Earthquake?
• Earthquake is measured using the Richter Scale• The Richter scale is a standard scale used to compare
earthquakes. • The device was developed in 1935 by Charles F. Richter
How is the magnitude of Earthquake measured?
Seismograph:• A network of geological monitoring stations,
each with instruments that measure how much the ground shakes over time
• The goal of a seismograph is to accurately record the motion of the ground during a quake
• Seismographs record a zigzag trace that shows how the ground shakes beneath
Primar
y Waves
Surface Waves
Surface Waves
Micro• Magni
tude less than-3.0
Minor• Magnitu
de in the rage of 3.0 to 3.9
Light• Magnitude
in the rage of 4.0 to 4.9
Moderate• Magnitude
in the rage of 5.0 to 5.9
Strong• Magnitude
in the rage of 6.0 to 6.9
Classification of EarthquakeMajor• Magnitude in the rage of 7.0 to 7.9
Great•Magnitude is greater than or equal to 8.0
Charles Richter's original formula was:
M= logA + 3log8t -2.92
Where: M= magnitude
A = the maximum displacement in millimeters measured on a Wood-Anderson seismograph
t = the time in seconds between the arrival of the P and S waves
Formula to calculate the magnitude of Earthquake
• If the maximum displacement is 23 millimeters and the time between the arrival of the P and S waves is 40 seconds. calculate the magnitude of earthquake.
• Sol: M= logA + 3log8t - 2.92 M= log(23) +3log(8 x 40) -2.92
M= 1.36 + 7.52 - 2.92 M= 5.96
Example: