Seismic station z is 800 kilometers from the epicenter book

Using graphs if a seismic station is 2500 kilometers from the earthquakes. The diagram shows three seismograms of the same earthquake recorded at three different seismic stations, x, y, and z. Distance from the epicenter to the seismic station is. To determine the distance of an earthquake epicenter. Base your answers to questions 31 and 32 on the map below. Approximately how long did it take the pwave to travel to station.

Scientists have inferred the structure of earths interior mainly by analyzing. Seismic site effects are related to the amplification of seismic waves in superficial geological. How long did it take the first swave to travel 500 kilometers to reach this seismic station. A seismic station is 2,000 kilometers from an earthquake epicenter. Station book listings international seismological centre. For the stations that are less than 800 km in distance to the earthquake, plot the sp times you found in seconds on the sp difference in travel times curve. S wave if the seismic station is kilometers from the earthquake epicenter. Calculating the epicenter of earthquakes main concept seismology is the study of.

Finding the distance to the epicenter from a seismic station. Point d represents a location at the boundary between the core and the mantle. A coordinate system has been placed on the map to describe locations. Chapter 2 seismic wave propagation and earth models gfzpublic. Why are three seismographs needed at each seismic station. There are two types of seismic waves associated with every earthquake, called p and s waves. Take a scale and measure the distance 07 mints of 4 mints on yaxis time in minutes from the epicenter by using the figure 6. Locating and measuring earthquakes putting down roots in. If we know what those two speeds are, and measure the time interval between the p and s arrivals at the seismic station, we can easily calculate how far the epicenter was from that seismic station. Much of the material in the remaining chapters of this book will deal with. Approximately how far away from station z is the epicenter. The homogeneous medium gives us simple straightline raypaths to simplify the algebra.

The station book may be searched by station codes, or by defining a search region. Seismographs are devices that record the earthquakes and do so by showing major waves patterns that is pwaves, swaves and lwaves. All the data are transmitted automatically to caltechusgs in pasadena for processing and distribution of information such as epicenters, magnitudes, and shakemaps. Assuming that swaves travel at 5 kms, it will take 800 s min. Examine the graph of seismic wave travel times middle graph onthis page. In order to locate the epicenter of this earthquake, you need to estimate the time interval between the arrival of the p and s waves the sp interval on the seismograms from three different stations. What is the difference between the arrival time of the first pwave and the arrival time of the first swave recorded at this station. Use the graph you made and the traveltime tool to estimate the distance to the epicenter if the sp lag time is 56. The lag time between them is directly related to the distance that the waves travel. Tracings made at three separate seismic stations are needed to locate an earthquake epicenter. The distance between an earthquake epicenter and the location of a seismographs can be calculated because. Notice that most of the groundshaking is associated with the surface waves. The map shows point x, which is the location of an earthquake epicenter, and point a, which is the location of a seismic station.

What is the distance of the epicenter from seismic station. Because they each travel with different speeds, seismologists can determine the distance from a seismic station. The distances from each seismic station to the earthquake epicenter have been drawn on the map. The first surface wave group arriving at a seismic station at the epicenter. The arrival times of the pwaves and swaves are indicated on each tracing. A complete list of stations is also available 2 mb is size. The vertical velocity vz of the ground surface motion was measured by. Determine the distance, in kilometers, from massena to the epicenter of this earthquake.

Epicentral distance is the distance separating the epicenter and the recording seismic station. Each station records seismic waves from both near and distant earthquakes. Earth science new york regents august 2002 exam questions. Base your answers to questions 9 through 11 on the map below, which shows seismograph recording stations at locations a, b, and c. Seismic stations detect earthquakes by the tracings made on seismographs.

Because p and s waves travel at different velocities, the p wave arrives at a seismic station ahead of the s wave. At what time did the first swave arrive at this station. For more information regarding can you solve for the distance of the epicenter from the seismic station given that the sp interval is about 10 minutes, please open this given link. Nonlinear acoustic waves in the viscous thermosphere and. Wave travel time from the epicenter to the seismic station can be estimated fro the travel charts. When an earthquake occurs, vibrations initiated by fracturing of the earths crust radiate outward from the point of fracture. The distance of the epicenter of the earthquake from the seismic station is calculated according the difference in arrival time between the two types of seismic waves s waves and p waves. The arrival time of the first earthquake pwave at a s a. The epicenter is the point on earths surface directly above an earthquake. So generally, errors on depth determinations are somewhat greater than on location determinations. The earthquake occurred as the result of thrust faulting on the.

Locating the epicenter and determining the magnitude of an. A6 mm 40 sec b9 mm 40 sec c15 mm 00 sec d19 mm 00 sec 14. Determining the earthquake distance you can now determine the distance from each seismic recording station to the earthquakes epicenter using the known times of travel of the s and p waves. Thus, sp lag time can be used to calculated distance to the epicenter of an earthquake. The question is a bit vague but i will explain as best as i can. Feb 14, 2010 a seismic station is a laboratory that has equipment that can detect, monitor and record earthquakes locally or anywhere in the world. As an alternative to the search page, the listings page categorises stations by. Let t and t i be the origin time of the earthquake and the arrival time at the ith station, respectively. Approximately how long did it take the pwave to travel to station z. The epicenter is the point on the surface of earth directly above the focus. Base your answer to the following question on the diagram and map below. The sumatra earthquake and tsunami december 26, 2004. Long period seismogram zcomponent showing typical global phases.

How long would it take for the first swave to arrive at seismic station 4,000 kilometers from the epicenter. A seismic station is a laboratory that has equipment that can detect, monitor and record earthquakes locally or anywhere in the world. If you fill in either the site name or the network affiliation, you may not enter anything in the network code andor station fields. Points a, b, and c represent seismic stations on earths surface. Seismic station x is 800 kilometers from the epicenter. How long did it take the first swave to travel 500 kilometers to.

The hypothetical seismogram at the top of the page shows how to measure the amplitude. This book is intended for everyone processing earthquake data, both in the observatory routine and. This volume is placed as a pdf file on the attached handbook cd, under the directory\48. Locating the epicenter of an earthquake introduction. The time it takes for the first s wave to reach the station. According to the earth science reference tables, how long does it take an swave to travel from. The earthquake epicenter was located along the pacific coast several hundreds kilometers from mexicocity, the seismic shaking was however extremely strong leading to very large damages figure 2 displays the recordings performed at different distances from the epicenter during the earthquake sequence. Seismic waves from the earthquake are detected at two recording stations.

High school earth sciencemeasuring and predicting earthquakes. Base your answer to the following question on the map below. Because they each travel with different speeds, seismologists can determine the distance from a seismic station to an epicenter. The earthquake creates vibrations in the ground called seismic waves. Dec 12, 2017 tutorial on how to find the arrival times of p and s waves from a seismogram for one station to determine distance to the epicenter and origin time of the earthquake also shows how to use page. The sequence of problems below will show you how this is done.

A seismic station 4000 kilometers from the epicenter of an earthquake records the arrival time of the first pwave. In this case if the epicenter is 3200 km from the seismic station then the swave will take 11 mins 10 sec. Lets say that they know that an earthquakes epicenter is 50 kilometers from kansas city. Figure 2 use the amplitude to derive the magnitude of the earthquake, and the distance from the earthquake to the station. If a seismic station is 3200 km from an earthquake. Find the epicenter of an earthquake polk county school. What is the time of arrival of an swave for a station that recorded the same event but 6000 km from the epicenter. International handbook of earthquake and engineering seismology, part a.

Iris staff and subawardees oversee the construction, operation, and maintenance of seismic networks and related data facilities utilized by a wide sector of the earth science community. They travel in every direction away from the source of an earthquake called the epicenter. What time was it at the station when the earthquake occurred. Calculating the epicenter of earthquakes maple programming help. Note the simple transient waveform wavelet of p in the zcomponent of fig. Interactive deep structures in ohio seismic station locations seismic station data seismic magnitudeintensity scales scales comparison chart magnitude scale defined mercalli scale defined what is a digital seismograph. This is a set of simulations that demonstrate how seismic waves are used to. The cartesian coordinates of the true hypocenter and the ith seismic station are x, y, z and x i, y i, z i, respectively.

How long would it take for the first swave to arrive at. Analog seismograms from seismic stations in north america may thus. This material is discussed in the earthquakes chapter of your textbook. Ny29 shows a plot of how the travel times of pwaves and swaves are related to the distance from an earthquake s epicenter.

What is the distance between the seattle seismic station. Hence, the distance from the earthquake epicenter to the seismic station is 3,000 miles. Earth science new york regents august 2005 exam base your answers to questions 63 and 64 on the diagram below, which shows two seismogram tracings, at stations a and b, for the same earthquake. Approximately how long will an swave take to travel from the epicenter of the same. A pwave takes 8 minutes and 20 seconds to travel from the epicenter of an earthquake to a seismic station. Curated exercise 11 answers oxford university press. Approximately how long did it take the pwave to travel to station x. A seismic station 4000 kilometers from the epicenter of an. Locating the epicenter, determining the magnitude, and.

The observed maximum amplitude depends on how far the seismic station is from the epicenter, such that the observed maximum amplitude diminishes with distance from the epicenter. The location of an earthquakes epicenter point on the earths surface directly above the. The tsunami generated by this quake moved at an average speed of about 600 kilometers per hour. The earthquake pwave and swave travel time graph p. Generally speaking, at increasing distance from the epicenter the wave. Locating the epicenter the source of an earthquake is called the focus, which is an exact location within earth were seismic waves are generated by sudden release of stored elastic energy. Identify the information shown on the seismogram that was used to determine that the distance to the epicenter was 500 kilometers.

What method is used to determine the epicenter of an earthquake. Which recording station is farther away from the epicenter. When each point that is that distance away from kansas city is marked, the marks create a circle. Nearly 3000 seismic stations distributed worldwide have been systematically. Seismograms are a complicated mixture of source radiation effects such as the spectral content and relative amplitude of the p and swave energy that is generated at the source, propagation phenomena such as multiple arrivals produced by reflection and transmission at seismic impedance boundaries or at the surface, and frequency bandlimiting effects of the recording. Seismic site effects have been first evidenced during the 1985 mexico city earthquake. There is a longer sp lag time at the station closer to the explosion. This graph translates the difference in arrival times of the p waves and s waves into distance from the epicenter to each station. Iris operates many prominent geophysical facilities. What is the distance of the epicenter from the seismic. Seismic station z is 1,700 kilometers from the epicenter. Approximately how far away from station y is the epicenter. Earthquake monitoring in southern california for seventyseven.