The Scenario A large earthquake has happened You

The Scenario: A large earthquake has happened. You need to find the earthquakes epicenter to send help. The process of epicenter location has been used for over 50 years. Read the 1 st paragraph of the Packet

Read thethe 2 ndfirst andparagraph…. 3 rd paragraph. . . Though relationship. . Read There arethe hundreds…. Steps to “Calculating an Epicenter” Step #1 Calculate the S-P Interval (subtract) Step #2 Use the Time/Distance chart to determine the distance in km. (Record Data) Step #3 Measure the highest amplitude in mm. (Record Data) Step #4 Using the nomogram, use the amplitude and distance to determine the magnitude. A ruler would be helpful in drawing a straight line. Step #5 Use the distance from Step #2 along with the scale at the bottom of the map. Determine the correct distance on the compass and draw a circle around the appropriate seismic station.

In order to do the “Earthquake epicenter” activity, there a few things you should know about reading and understanding earthquake data.

Intervals: You will have to determine the intervals. You may have to GUESSTIMATE a little 1) What is the interval between each line on the Y- Axis (amplitude)? 10 mm seconds

Intervals: You will have to determine the intervals. You may have to GUESSTIMATE a little 2) What is the interval between each line on the X – Axis(magnitude)? 2 Seconds seconds

Intervals 3) What is the interval between each line on the Y- Axis (time)? 1 second

Intervals 4) What is the interval between each line on the X- Axis (distance)? 20 km

Map Distances 7) Open to the map on pg. 3, using the ruler and scale what is the distance from Reno to Eureka? 380 – 385 km 5) What is the 6) interval between the large to and large small lines on the scale? 100 km 50 km km

Map Distances 7) What is the distance from Phoenix to Las Vegas? ~425 km km This mean approximately. Your number may be slightly higher or lower.

This concludes the “Training Session” You know the basics involved with determining an earthquakes epicenter.

Go to Page 2 of the Earthquake information packet Eureka, Ca Seismic Station

Step #1 Calculate the S-P Interval (subtract) P-Wave S-Wave What is the number? 49 seconds This is a very important step try to be as accurate as possible.

Go to Page 1 of the Earthquake DATA Record the number Here Station Eureka, CA S-P Interval Distance 49 sec Amplitude mm Elko, NV sec km mm Las Vegas, NV sec km mm

Go to Page 2 of the Earthquake information packet Step #2 Use the Time/Distance chart to determine the distance in km. (Record Data) The S-P Interval was 49 sec. Follow 49 across until it hits the S-P interval line, then follow it down to determine the distance. What is it? 478 km

Record the number Here Station S-P Interval Distance Amplitude 49 sec 478 km mm Elko, NV sec km mm Las Vegas, NV sec km mm Eureka, CA

Step #3 Measure the maximum amplitude in mm. (use the largest wave) (Record Data) ` Look Here And Here Record Here The number is? ? 285 mm Station S-P Interval Distance Amplitude 285 49 sec 478 km Elko, NV sec km mm Las Vegas, NV sec km mm Eureka, CA mm

Using the nomogram, plot the distance(km) and amplitude(mm) to determine the magnitude. A ruler would be helpful in drawing a straight line. Station S-P Interval Distance Amplitude 49 sec 478 km 285 mm Elko, NV sec km mm Las Vegas, NV sec km mm Eureka, CA Where it crosses is the earthquakes magnitude on the Richter Scale.

Use the distance from Step #2 along with the scale at the bottom of the map. Determine the correct distance on the compass and draw a circle around the appropriate seismic station. Station S-P Interval Distance Amplitude Eureka, CA 49 sec 478 km 285 mm Elko, NV sec km mm Las Vegas, NV sec km mm This step needs to be done slowly and carefully

Eureka, CA Distance 478 km Don’t worry if it goes off the paper.

Northern California Elko, NV Seismic Station

Step #1 Calculate the S-P Interval (subtract) P-Wave This is the most important step try to be as accurate as possible. S-Wave Elko, NV Seismic Station What is the number? 72 seconds Record the number Here Station Eureka, CA Elko, NV Las Vegas, NV S-P Interval 49 72 Distance Amplitude sec 478 km 285 mm sec km mm

Step #2 Use the Time/Distance chart to determine the distance in km. (Record Data) The S-P Interval was 72 sec. Follow 72 across until it hits the S-P interval line, then follow it down to determine the distance. What is it? 703 km

Record the number Here Station S-P Interval Distance Amplitude Eureka, CA 49 sec 478 km 285 mm Elko, NV 72 sec 703 km mm sec km mm Las Vegas, NV

Step #3 Measure the maximum amplitude in mm. (use the largest wave) (Record Data) Look Here And Here Record Here The number is? ? 60 mm Station S-P Interval Distance Amplitude Eureka, CA 49 sec 478 km 285 mm Elko, NV 72 sec 703 km 60 mm sec km mm Las Vegas, NV

Using the nomogram, use the amplitude and distance to determine the magnitude. A ruler would be helpful in drawing a straight line. Station Eureka, CA Elko, NV Las Vegas, NV S-P Interval Distance Amplitude 49 sec 478 km 285 mm 72 sec 703 km 60 mm sec km mm

Use the distance from Step #2 along with the scale at the bottom of the map. Determine the correct distance on the compass and draw a circle around the appropriate seismic station. Station S-P Interval Distance Amplitude Eureka, CA 49 sec 478 km 285 mm Elko, NV 72 sec 703 km 60 mm sec km mm Las Vegas, NV

Elko, CA Distance 703 km Don’t worry if it goes off the paper.

Northern California Las Vegas, NV Seismic Station

Step #1 Calculate the S-P Interval (subtract) P-Wave This is the most important step try to be as accurate as possible. S-Wave Las Vegas, NV Seismic Station What is the number? 64 seconds Record the number Here Station S-P Interval Distance Amplitude sec 478 km 285 mm Elko, NV 49 72 sec 703 km 60 mm Las Vegas, NV 64 sec km mm Eureka, CA

Step #2 Use the Time/Distance chart to determine the distance in km. (Record Data) The S-P Interval was 64 sec. Follow 64 across until it hits the S-P interval line, then follow it down to determine the distance. What is it? 624 km

Record the number Here Station S-P Interval Distance Amplitude Eureka, CA 49 sec 478 km 285 mm Elko, NV 72 sec 703 km 60 mm Las Vegas, NV 64 sec 624 km mm

Step #3 Measure the maximum amplitude in mm. (use the largest wave) (Record Data) Look Here And Here Record Here The number is? ? 100 mm Station S-P Interval Distance Amplitude Eureka, CA 49 sec 478 km 285 mm Elko, NV 72 sec 703 km 60 mm 64 sec 624 km 100 mm Las Vegas, NV

Using the nomogram, use the amplitude and distance to determine the magnitude. A ruler would be helpful in drawing a straight line. Station S-P Interval Distance Amplitude 49 sec 478 km 285 mm Elko, NV 72 sec 703 km 60 mm Las Vegas, NV 64 sec 624 km 100 mm Eureka, CA

Use the distance from Step #2 along with the scale at the bottom of the map. Determine the correct distance on the compass and draw a circle around the appropriate seismic station. Station S-P Interval Distance Amplitude Eureka, CA 49 sec 478 km 285 mm Elko, NV 72 sec 703 km 60 mm Las Vegas, NV 64 sec 624 km 100 mm

Las Vegas, NV Distance 624 km Don’t worry if it goes off the paper.