<p>Unit 3 - Notes / Student Guide</p><p>Earthquake Waves, the ESRT, and You</p><p>What does the ESRT chart tell us?</p><p> The amount of ______that waves have traveled (x-axis)  The amount of ______that waves have traveled (y-axis)  The distance to the epicenter. (difference in arrival times)</p><p>Ex: A) How much time does a P wave take to travel 4000 km? ______</p><p>B) How much distance can an S wave travel in 17 min? ______</p><p>“Talking Heads”</p><p>1. How much time does a P wave take to travel 6200 km? ______</p><p>2. How much time does an S wave take to travel 3400 km? ______</p><p>3. How much distance can an S wave travel in 9 min 20 sec? ______</p><p>4. How much distance can a P wave travel in 7 min 40 sec? ______</p><p>5. ______</p><p>6. ______</p><p>How can we find the distance to an epicenter? (procedure)</p><p>Ex: Finding the Distance to the Epicenter using Seismograms</p><p>If a seismograph recording station records the arrival times of the P and S waves, how is the distance to the epicenter determined? We use the difference in arrival times between the P and S waves.</p><p>Step 1: Determine the difference in arrival times of the P and S waves.</p><p>Step 2: Mark the time difference from the y-axis on the edge of your paper.</p><p>Step 3: Align the marks vertically between the wave curves on the graph.</p><p>Step 4: Read the value from the x-axis to find the distance to the epicenter.</p>