How do we Locate the Epicenter of an Earthquake?
In the last lesson we learned how we can use a seismogram to determine the distance to the epicenter. Aside from knowing the distance we may want to also know where in the world the earthquake occurred.
TO FIND THE LOCATION OF THE EPICENTER WE NEED 3 SEISMOGRAMS

Step 1: Find Distances to the Epicenter
The first thing we need to do is figure out the distance from each seismogram to the epicenter, using the same method we learned in the last lesson.

Seismogram 1:
Difference in arrival times = 4 min 0 sec
Distance to epicenter = 2,800 km
Seismogram 2:
Difference in arrival times = 5 min 40 sec
Distance to epicenter = 4,000 km
Seismogram 3:
Difference in arrival times = 3 min 0 sec
Distance to epicenter = 1,800 km
Step 2: Draw Circles

Now that we know the distance from each location to the epicenter, we need to mark those distances on a map. However, since we don't know the direction to the epicenter, we need to DRAW CIRCLES AROUND EACH STATION WITH A RADIUS EQUAL TO THE DISTANCE WE JUST FOUND.
