Question

The San Andreas fault is a dextral (right-lateral) strike-slip fault that runs between Los Angeles and San Francisco. This means that Los Angeles is slowly approaching San Francisco. Assuming the average slip rate of 2.1 cm/year remains constant, in about how many years will Los Angeles be directly west of San Francisco? Los Angeles is presently 519 km from San Francisco. Choose the best answer below. Hint: 1 cm = 0.00001 km.

Answer 1

We are going to use the fact that 1cm = 0.00001km to convert 2.1cm/year to 0.000021km/year. Now, since Time = Distance/Velocity, we replace the values from our problem to get:  Time = 519km/ (0.000021km/year) which is equal to 24714285.71 years. We conclude that Los Angles will be directly west to San Francisco in a little less than 25 million years.