A graph
Works Cited
Harris, Tom and Patrick J. Kiger. “How
Earthquakes Work”. HowStuffWorks. Web. 12
September 2015.
<http://science.howstuffworks.com/nature/natural
-disasters/earthquake6.htm>
“How are Earthquake Magnitudes Measured?”.
UPSeis. Web. 9 September 2015.
<http://www.geo.mtu.edu/UPSeis/intensity.html>
“Measuring the Size of an Earthquake”. USGS.
24 February 2014. Web. 10 September 2015.
<http://earthquake.usgs.gov/learn/topics/measure.
php>
Menke, William. “How Was The Richter Scale
for Measuring Earthquakes Developed?”.
Scientific American. 11 April 2005. Web. 12
September 2015.
<http://www.scientificamerican.com/article/howwas-the-richter-scale/>
A graph representing the magnitude levels
from -1 to 8.9 (the highest recorded) and
some of the earthquakes with these recorded
magnitude levels.
“Richter Scale”. SMS Tsunami Warning. Web. 12
September 2015. <http://www.sms-tsunamiwarning.com/pages/richter-scale#.VfgczZ2qqko>
Stapel, Elizabeth. “Logarithmic Word Problems”.
Purplemath. Web. 10 September 2015.
<http://www.purplemath.com/modules/expoprob.
htm>
The Richter
Scale
By Reza Roovers
What is the
Richter Scale?
The Richter Scale is a standard of
measurement used to calculate the
magnitude, or the amount of energy
released, of earthquakes. The
Richter Scale uses the information
obtained from the seismograph that
records the force and duration of
Earthquakes.
The Richter Scale rates the
magnitude of an earthquake.
Earthquakes recorded below level 2
.0 are micro quakes that are not
really felt, while the highest was no
higher than 9, which was very big
and caused a lot of destruction.
The Richter Scale was invented by
Charles F. Richter from the
California Institute of Technology in
1935 as a mathematical tool to
compare the size of earthquakes. He
wanted to find a simpler way to
compare earthquakes as there were
big and small earthquakes. By using
the information from the
seismograph, he was able to
calculate and simplify by
representing it with a simple digit
number for the magnitude.
Calculations
The way the Richter Scale calculates the
magnitude is by measuring the ground
vibrations or amplitude. The magnitudes are
based with a logarithmic base 10, in which
every time you go up a whole number in the
scale, the ground motion recorded by the
seismograph goes up 10 times. The formula
used is this:
R = log[ I ÷ I0 ]
I represents the terms of multiples of the
threshold intensity, while the I0 represents the
movement that can be barely detected,
known as the “threshold quake”.
The original magnitude scale was to record
any of the earthquakes ranging between 0
and 700km. However, as earthquakes can
cause waves, which would then travel into
and through earth, two formulas were
created: the mb and MS.
Career
The Richter Scale is used by seismologists to
measure earthquakes all over the world.
Earthquakes are recorded everyday, but many
of them are micro quakes, which are small.
Seismologists also use the less heard Mercalli
Scale to measure the intensity of the
earthquakes. The Richter scale only gives
people the magnitude number, which only
gives people some general idea of how big
the earthquake is.
The Mercalli scale specifies its intensity level
rather than magnitude level. But that scale
isn’t heard about so often. Now, there are
other scales that are also used by
seismologists to measure the magnitude of
the earthquake size, which is more accurate,
but the Richter scale is still a commonly
accepted standard of measurement.
mb = log10(A/T) + Q(D,h)
In the standard body-wave magnitude
formula, A represents amplitude, T
corresponds period (in seconds), Q(D,h) is a
correction factor as a function for distance, D
for degress between the epicenter and station
and focal depth and h in kilometers. The
standard surface-wave formula is:
MS = log10 (A/T) + 1.66 log10 (D) + 3.30
A seismograph