On January 2, 2011, a 7.1 magnitude earthquake struck the central coastal area of Chile, approximately 45 miles northwest of Temuco. No major damage or injury was reported when the earthquake hit, though the quake was felt 370 miles away in Santiago. Find the intensity of the earthquake and express its intensity in terms of the intensity of a standard earthquake, that is, I 0 . Solution Richter scale, R = log(I/Io) = 7.1 Thus, I/Io = 10^7.1 Thus, I = 12.59*10^6 times of Io .

1. On January 2, 2011, a 7.1 magnitude earthquake struck the central coastal area of Chile,
approximately 45 miles northwest of Temuco. No major damage or injury was reported when the
earthquake hit, though the quake was felt 370 miles away in Santiago. Find the intensity of the
earthquake and express its intensity in terms of the intensity of a standard earthquake, that is, I 0 .
Solution
Richter scale, R = log(I/Io) = 7.1
Thus, I/Io = 10^7.1
Thus, I = 12.59*10^6 times of Io