* Your assessment is very important for improving the workof artificial intelligence, which forms the content of this project
Download Finding an earthquake epicenter Geologists who study earthquakes
Seismic retrofit wikipedia , lookup
2009–18 Oklahoma earthquake swarms wikipedia , lookup
Casualties of the 2010 Haiti earthquake wikipedia , lookup
Kashiwazaki-Kariwa Nuclear Power Plant wikipedia , lookup
1908 Messina earthquake wikipedia , lookup
2011 Christchurch earthquake wikipedia , lookup
2010 Canterbury earthquake wikipedia , lookup
Earthquake engineering wikipedia , lookup
1880 Luzon earthquakes wikipedia , lookup
1570 Ferrara earthquake wikipedia , lookup
2008 Sichuan earthquake wikipedia , lookup
2010 Pichilemu earthquake wikipedia , lookup
1992 Cape Mendocino earthquakes wikipedia , lookup
Earthquake (1974 film) wikipedia , lookup
1960 Valdivia earthquake wikipedia , lookup
Finding an earthquake epicenter Geologists who study earthquakes are called seismologist. If you were a seismologist, you would receive data from seismographs all over the world. Each recording stations I constantly collecting data on all tectonic disturbances in the crust. Within minutes of an earthquake, seismographs would record the arrival times of the P-waves and S-waves. Since P-waves travel faster than s-waves, if there is a longer period of time from when the P-waves arrive to when the S-waves arrive, you know that the epicenter is located farther from the recording station. You use the P and S wave data from at least three recording stations to pinpoint the location of an earthquake epicenter. If there is information from only one station, the epicenter of the earthquake could at any point on that circle. If there is information from two stations, the circles intersect at two points, so there are two possible epicenters. With three stations, the circles intercept at only one point, which must be the epicenter. Procedure: 1. 2. 3. 4. 5. Look at the chart indicating the difference in arrival times from P and S waves from the three recording stations. Use your time travel curve to determine the distance to the epicenter from each city. Using the scale on your map, and your compass, draw a circle with a appropriately sized radius around the city. This represents the possible location of the epicenter in all directions. After circles are drawn, the point where they intersect represents the location of the epicenter. Describe the location of each epicenter using the closest city. Earthquake # 1 City Difference in arrival time of P& S Waves Earthquake # 2 Distance to City Difference epicenter in arrival determined time of P from travel and S time curve Waves Km Denver 2:20 Km New York 2:00 km Miami 3:00 Earthquake # 3 Distance to City Difference epicenter in arrival determined time of P from travel and S time curve Waves Km Salt Lake 3:25 Km Miami 3:00 km Chicago 2:30 Distance to epicenter determined from travel time curve Km Km km Seattle 2:00 Denver 2:30 Houston 4:00 Questions: 1. What are the locations of the earthquakes? Earthquake #1 - ______________________Earthquake #2 ______________________Earthquake #3 - ______________________ 2. Why do you need at least three seismic recording stations? 3. Which earthquake wave travels faster? ________________________________ 4. What happens to the difference in arrival times between S and P waves as you get further from the epicenter? 5. If you notice there are many epicenters located in one area of the earth, what does that tell you about that area? What type of plate boundary would be present?