If the lag time were measured at a location closer to the epicenter, The period of a wave is the time between two adj, How does the period of the P waves compare to t. Use data from seismograms to locate the epicenters of earthquakes. It travels faster than the same earthquake's S wave (almost double the speed) and is similar to sound waves. This is determined by the P-and S-wave arrival times. Type text, add images, blackout confidential details, add comments, highlights and more. 13.4: Locating an Earthquake Epicenter - Geosciences LibreTexts How can you locate an earthquake's epicenter? The LibreTexts libraries arePowered by NICE CXone Expertand are supported by the Department of Education Open Textbook Pilot Project, the UC Davis Office of the Provost, the UC Davis Library, the California State University Affordable Learning Solutions Program, and Merlot. At least 3 earthquake recording stations are required to find the location of the earthquake epicenter. Since the 1970s, the use of the Richter magnitude scale has largely been replaced in the scientific community by the moment magnitude scale (MMS). 0000008088 00000 n (Grades 12 Earthquake Location Lab Answer Key Full PDF - www.yvc.moeys.gov This is determined by the P-and S-wave arrival times. The farther away the epicenter is, the greater the difference . How does the Mad Scientist. Pwaves have the greatest velocity and reach the, seismic station first. Multiply the difference by 8.4 to estimate the distance, in kilometers, from the seismograph station to the epicenter. Make arrangements so that each student group has a computer with Internet access. waves from a distant earthquake. The point of origin of an earthquake is called its focus and the point on the Earth's surface directly above the focus is the epicenter. 0 When seismic data is collected from at least three different locations, it can be used to determine the epicenter by where it intersects. One seismogram indicates the distance to the epicenter. 0000002658 00000 n P wave: The first seismic wave of an earthquake. 0000003254 00000 n What are those limits? Introduction: Before student pairs look at the Earthquakes Living Lab, direct them to complete the Engage section of the Finding Epicenters and Measuring Magnitudes Worksheet, which asks them to apply any prior knowledge and/or speculate as to what the Richter magnitude scale is and what an epicenter is. hb```f``Rl@ (l"`+uk?0.a~@6Vm;| G3f`75@v@Wz|A4#w9{(` ) In this investigation, participants will understand that S and P waves are used to find the epicenter of an earthquake by using seismograph data to triangulate an epicenter. Zip. Finding the epicenter of an Earthquake by Ah - Ha Lessons 5.0 (1) $3.00 PDF Activity This lesson teaches the student the process scientists use to locate the epicenter of an EQ. earthquake - shaking and vibration of Earth's surface. The western U.S. has more faults than the eastern U.S., and therefore the western U.S. has more earthquakes. PDF Lecture 3 Activity: Locating an Earthquake Epicenter determine the epicenter using the S P (S minus P) method. Short for "primary wave" or "pressure wave." Download. Entering the three maximum amplitudes generates a nomogram, a graphical device that simplifies the process of estimating magnitude from distance (determined earlier in the tutorial from the S-P interval process) and amplitude. aqmd. 0000001777 00000 n : an American History (Eric Foner), Principles of Environmental Science (William P. Cunningham; Mary Ann Cunningham), Forecasting, Time Series, and Regression (Richard T. O'Connell; Anne B. Koehler), Chemistry: The Central Science (Theodore E. Brown; H. Eugene H LeMay; Bruce E. Bursten; Catherine Murphy; Patrick Woodward), Biological Science (Freeman Scott; Quillin Kim; Allison Lizabeth), Campbell Biology (Jane B. Reece; Lisa A. Urry; Michael L. Cain; Steven A. Wasserman; Peter V. Minorsky), How many minutes elapsed between the arrival of the first P wave and. So the difference in the P- and S-wave arrival times determines the distance between the epicenter and a seismometer. All the arcs should intersect at a common point - the epicenter. epicenter: A point on the Earth's surface that is directly above the place where the underground forces of an earthquake originate. S wave: The second seismic wave of an earthquake. Activity 4: Locating an Earthquake Epicenter Examining Seismograms The three basic types of seismic wave generated by an earthquake at its focus are Pwaves, Swaves, and Surface waves. PDF Locating An Earthquake Epicenter Lab Answers - Full PDF 0000001675 00000 n Accessibility StatementFor more information contact us atinfo@libretexts.orgor check out our status page at https://status.libretexts.org. farther from the epicenter of an earthquake? 0000030968 00000 n Using online resources and simulations available through the Earthquakes Living Lab, students explore the consequences of subsurface ground type and building height on seismic d Seismographs are measuring devices designed by engineers and used by researchers to determine the locations and magnitudes of earthquakes. Travel-time graphDistance in Miles, Copyright 2023 StudeerSnel B.V., Keizersgracht 424, 1016 GC Amsterdam, KVK: 56829787, BTW: NL852321363B01, seismogram. Accessed December 11, 2013. http://en.wikipedia.org/wiki/Moment_magnitude_scale, Novak, Gary. To accurately locate an earthquake epicenter, records from three. Choose an answer and hit 'next'. to the lag time measured at this location? DocHub v5.1.1 Released! Using the real-world data in the living lab enables students and teachers to practice analyzing data to solve problems and answer questions, in much the same way that scientists and engineers do every day. Answer the following questions in the spaces provided. hbbd``b`$C`q9 X_$_g`bdxc`X Using this resource students find the arrival times of P-waves and S-waves using a seismogram. 0000055643 00000 n 12), Seek, evaluate, and use a variety of specialized resources available from libraries, the Internet, and the community to find scientific information on Earth's history A circle is drawn from each of the three different seismograph locations, where the radius of each circle is equal to the distance from that station to the epicenter. Describe the process of triangulation to locate an epicenter. H\0y E}g7$i(=K)"aj%v]vPcYloi@X3noGX{[XucOgkdF.>Ym^fwrQf;8_Nok3w\;?n_Hhc?>k\o[%DgwJ'3d.lTqDy_aJw! How does the period of the P waves compare to the period of the surface waves? 0000002094 00000 n Geologists use seismic waves to locate an earthquake's epicenter. Use Figure 5 and the travel-time graph in Figure 4 to determine . 0000001746 00000 n Note the differences in To complete the activity, some prior . 0000006011 00000 n Accessed December 11, 2013. http://earthquake.usgs.gov/aboutus/docs/020204mag_policy.php. So next, students compute the magnitude of this same earthquake by looking at the three simplified seismograms again, but this time selecting each's maximum S wave amplitude (height). Figure 13.10). Have students click on the Earthquakes Living Lab hyperlink in the top left in the earthquakes section. To abbreviate, use the symbol M (a capital M, plain text, no sub/superscripts) expressed to the nearest 0.1. Activity 4 Locating An Earthquake Epicenter Answers: Fill Out & Sign . How does the lag time change as you get farther and Civil engineers, who design houses, apartment buildings, schools, skyscrapers, bridges, highways, tunnels, water treatment facilities, factories and other structures, may use this data to help them create safer structures that are less likely to sustain damage during earthquakes. The calculated distance from each seismometer to the earthquake is shown as a circle. Overhead transparency of each of the handouts, Overhead projector (contact classroom teacher about this) and screen, Optional: overhead transparency or PowerPoint of, What do you know about the causes and impacts of Earthquakes? The seismometers are shown as green dots. Yw8SxGk}X3kfTfW& gk`41#'uf7"G\fsN4^8jC7[+%`qFLFKpFc In this activity, students use an online simulationVirtual Earthquakethat is accessible through the Earthquakes Living Lab interface, to locate the epicenter of an earthquake by making simple measurement on three seismograms, recordings of an earthquake's seismic waves detected by instruments (seismographs) far away from the earthquake. What is the For example, Earthquake Location 2 Using the skills that you acquired in the picking P and S arrivals, you can now locate an earthquake using real seismic records. miles from the epicenter of an 0000000856 00000 n 5 4. velocity, amplitude, and frequency of the Then do the same for the S-wave. Do you agree with this alignment? Follow this simple guide to edit Locating the epicenter of an earthquake worksheet answer key in PDF format online free of charge: Explore all the advantages of our editor right now! Focus. 0000004457 00000 n 6.17: Locating Earthquake Epicenters - K12 LibreTexts Students learn about factors that engineers take into consideration when designing buildings for earthquake-prone regions. earthquake. travel 3,000 miles. Use the graph to answer the questions that follow. Locating Earthquake Epicenter Worksheet Answer Key Then from the same recordings they determine the earthquake's magnitude, an estimate of the amount of energy released during the earthquake. 0000002383 00000 n Another method of locating an earthquake is to use the P-wave arrival-time minus origin-time (P - O) interval instead of distance. P and Swaves are body waves and travelthrough the interior of the earth. 17 Station St., Ste 3 Brookline, MA 02445. The nations most famous fault is the San Andreas Fault, which runs along a north-south trend in southern California, and happens to run directly through Los Angeles. 0000001562 00000 n As the drum rotated, t, pen recorded the arrival of P, S, and surface, between arrival of P and S waves is called, epicenter, the longer the lag time measured, velocity, amplitude, and frequency of the. 2. Conclude the activity with a class discussion (and perhaps homework questions) to share ideas and answers, as described in the Assessment section. 0000033429 00000 n important in helping seismologists determine the epicenter of the earthquake. How is the magnitude of an earthquake determined? Run through the investigation yourself and record the data, just to see how long it takes. If you can't find an answer to your question, please contact us. Then locate and click the link in the center of the page under the question: "How is an earthquake epicenter located and how is magnitude determined"? !D,X2:azTG)kPT~Mj 4>d w@O'. PDF ActivityEarthquake Location* - Cascadia Earthscope Earthquake and Draw your signature, type it, upload its image, or use your mobile device as a signature pad. 0000078100 00000 n The instrument detects and documents the intensity, direction and duration of ground vibrations, which are used to determine the epicenters and strength/magnitudes of earthquakes or other seismic events.