New Madrid quake. On December 16,1811,

an earthquake occurred near New Madrid, Missouri, that temporarily reversed the course of the Mississippi River. The quake had a magnitude of 8.8.
On October 17,1989,
a calamitous quake measuring 7.1
on the Richter scale occurred in San Francisco during a World Series baseball game on live TV. How many times as intense as the San Francisco quake was the New Madrid quake?

1 answer

The Richter scale is logarithmic, which means that an increase of one whole number represents a ten-fold increase in intensity. To compare the intensities of the New Madrid and San Francisco earthquakes, we can use the formula:

Intensity_Factor = 10^(Magnitude_1 - Magnitude_2)

Using the magnitudes of 8.8 for the New Madrid quake and 7.1 for the San Francisco quake:

Intensity_Factor = 10^(8.8 - 7.1) = 10^1.7 ≈ 50.12

So, the New Madrid earthquake was about 50 times as intense as the San Francisco earthquake.