1. Today Hand in your LAB and any other work. Hand in your LAB and any other work. Check the list in the back, if you owe something. Check the list in the back, if you owe something. Get out a half sheet of piece of paper, PUT YOUR NAME ON IT. Get out a half sheet of piece of paper, PUT YOUR NAME ON IT. When bell rings the quiz will start and you will have 1 minute per question to answer. When bell rings the quiz will start and you will have 1 minute per question to answer.

2. Question 1 Define a focus & an epicenter. Define a focus & an epicenter.

3. Question 2 What are the 2 scales used to measure size of EQ? What are the 2 scales used to measure size of EQ?

4. Question 3 Subtract these times: Subtract these times: 12:02:22 12:02:22 - 11:50:40 - 11:50:40

5. Question 4 What is the temperature at 4000km below the surface of the Earth? What is the temperature at 4000km below the surface of the Earth?

6. ANSWERS Define a focus & an epicenter. Define a focus & an epicenter. Focus is below ground where EQ happens Epicenter is on the surface above focus What are the 2 scales used to measure size of EQ? What are the 2 scales used to measure size of EQ? Mercalli & Richter Subtract Subtract 00:11:42 Temperature at 4000km Temperature at 4000km ~5800 o C

7. Steps to Find an Earthquake Epicenter Be careful today you need to be real accurate!

8. Steps (write this down) 1) 1) Find P wave arrival Find S wave arrival 2) 2) Find Difference (S-P) Subtract 3) 3) ESRT page 11 Use number from step 2 4) 4) Go to map and draw circle to scale at distance 5) 5) Repeat at least two more times

9. ESRT P 11 Each line = __________ Each line = _________ Think back to EQ waves LAB… Which wave is faster? What happens as you get further away?

10. Step 1: P and S wave arrival P-wave arrival time = ??? First big blip S-wave arrival time = ??? Second big blip P = 4 minutes S = 8 minutes

11. Step 2: Find Interval P = 4 minutes S = 8 minutes hr : min : sec S-wave 00:08:00 P-wave -00:04:00 00:04:00 minutes Take the 4 minutes and open your ESRT to pg 11. ALWAYS use hr : min : sec Format!

12. Step 3: ESRT pg 11 Find 4 minutes HERE (RED line) 1. Then, count the boxes or draw a line on scrap. 2. Then, slide the scrap or count the difference in between S & P waves 3. Read off distance on x axis 2800 km

13. Safety compass Safe?  Set center point to 0. Set center point to 0. Move arrow to distance. Move arrow to distance. Put your finger on circle and pen in arrow. Put your finger on circle and pen in arrow. Draw circle from city data is from. Draw circle from city data is from. 0100020003000 Safer ?  Be carful do NOT over turn the screw! Center circle Distance slider

14. Step 4: Map It! 0100020003000

15. Step 5: Do it again 1) 1) Find P wave arrival ~S wave arrival 2) 2) Find Difference (S-P) 3) 3) ESRT page 11 ~Use number from step 2 4) 4) Go to map and draw circle to scale at distance

16. Now what?? Where is the EQ? 0100020003000

17. Do it again 1) 1) Find P wave arrival ~S wave arrival 2) 2) Find Difference (S-P) 3) 3) ESRT page 11 ~Use number from step 2 4) 4) Go to map and draw circle to scale at distance

18. 0100020003000 EQ is Here

19. Let’s Review Step 1: Find the arrival times Step 2: Subtract S-P wave times (S-P interval) Look up on ESRT 11 the distance. Step 3: Look up on ESRT 11 the distance. Find the S-P interval on the Y-axis and then find that in between the P & S wave lines. Step : 4: Once you have 1 distance draw circle. Steps 5: Repeat at least 2 more times!

20. P-Wave travel time This is the time it takes for the P-wave to get to the recording station. This is the time it takes for the P-wave to get to the recording station. It’s simple to find! It’s simple to find! Use the epicenter distance you already found. Use the epicenter distance you already found. Go to that distance on your ESRT and follow a line up to the P-wave line. Go to that distance on your ESRT and follow a line up to the P-wave line. Follow to the left and read off the time! Follow to the left and read off the time!

21. Let’s try Subtract: Subtract: 12:00:0011:34:30 01:21:10 12:00:0011:34:30 01:21:10 -11:55:30 -11:30:50 -01:18:18 -11:55:30 -11:30:50 -01:18:18 Station (City) Arrival P-wave Arrival S-wave S-P time +/- (00:00:30) Distance +/- (200km) P-wave travel time A11:55:3012:00:00 B11:30:5011:34:30 C01:18:1801:21:10

23. Next 1. Practice page 33/34 Try it yourself FIRST! Then catch me for help. 2. Then, turn to page 35/36 Use data on board to complete the chart and find the epicenter! 3. Then, turn to page 37-40 This is may be your homework