**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. **