2.Measuring the force of earthquakes

Which of the following represents the most powerful earthquake?

Great Chilean, 9.5

The farther apart the P and S waves are on a seismogram, the farther away is the epicenter of an earthquake.

true

Select all of the answers that apply. Triangulation is a process to locate an earthquake. Which statements are true regarding this process?

-You must know the difference in the times that S waves and P waves arrive at a seismograph station to determine the distance to the epicenter. -You should draw a line from the center of the seismograph station to the epicenter to show its location. -Three seismograph distances must be mapped with circles and the point where they intersect is the epicenter

Select all of the answers that apply. Which of the following are signs that an earthquake may occur?

-foreshocks -changes in the magnetic properties of rocks

Match the earthquake measuring instrument with its correct description.

1 3 2

A seismograph records an earthquake, but scientists do not feel it. The earthquake has a magnitude _____.

< 2.0

The area where rock layers first move along a fault is the _____ of an earthquake.

focus