#### To determine

**To find:**

Intensity of 1906 earthquake.

#### Answer

Intensity of 1906 earthquake is log1016×107.1.

#### Explanation

**Calculation:**

Magnitude of an earthquake is log10IS,

where,* I* is the intensity of the quake and *S* is the intensity of a standard earthquake.

Magnitude of an Earthquake is log10IS,

The magnitude of 1989 Earthquake is **7.1**

Therefore

7.1=log10IS,

IS=107.1

So, intensity of 1989 Earthquake is I=107.1S.

It is given that intensity of 1906 Earthquake=16×Intensity of Earthquake 1989=16×107.1S.

So, magnitude of Earthquake on Richter Scale =log10intensity of 1906S

=log1016×107.1SS

=log1016×107.1

So, magnitude of an earthquake of 1906 on Richter Scale is log1016×107.1.

**Conclusion:**

Intensity of 1906 earthquake is log1016×107.1.