Concept explainers
Look at Figure 19-3. The earthquake occurred 7440 km from the seismograph. How fast did the P waves travel in km/s? How fast did the S waves travel? How long did the P waves and the S waves take to travel 100 km from the epicenter? Assume the wave speeds are constant.
The speed of
Answer to Problem 2P
The speed of
Explanation of Solution
Write the expression for speed of wave.
Here,
From the figure
Conclusion:
Substitute,
Substitute
The distance travelled from the epicenter is
Substitute
Substitute
The speed of
Want to see more full solutions like this?
Chapter 20 Solutions
Foundations of Astronomy
- An earthquake occurs 6,875 km from a seismograph. The P-waves arrive 11.6 minutes later. How fast is the P-wave traveling (in km/s)? If the lag time between P- and S-waves is 10.8 minutes, how fast are the S-waves traveling (in km/s)? Using the shadow of S-waves you determine that the radius of the core is 55% of the Earth's 6,378-km radius. How many kilometers from the surface is this (in km)? To calculate how fast the P-waves are traveling, we need to divide the distance the waves travel by the time. vP = d s vP = km/sarrow_forwardIn marine seismic exploration, a seismic source such as an air gun or water gun is used to generate seismic energy. All seismic sources deployed in the water have what feature in common?a. They generate P-waves onlyb. They generate S-waves onlyc. They generate both P and S wavesd. They generate both P and SV wavesarrow_forwardMEND ADNAN AYDIN ADNAN MENDERES ÜN" ONLINE SINAV PORT CAVERSHE TES 1803031 1. Choose the irrotational flow field below. 181803031 181803031 O A) u= y² v= x² O B) u= -6y v= 3x- 1803031 O C) u= 3y v= 6x O D) u= 6y v= x² O E) u= -6x v= 3y Bu soruyu cevaplamadan geçmek için bu seçeneği işaret. Sorunun C AYDIN 81803031 101003031arrow_forward
- When looking at first arrival times in a seismic refraction survey, what relationship between the layer velocities allow us to determine the velocity of layer 3 and know that it is in fact the velocity for layer 3?a. V1 < V2 < V3b. V2 < V1 < V3c. as long as V2 > V3d. V1>V2<V3arrow_forwardLook at Figure 19-3. The lag time is the difference between when the P waves arrived and when the S waves arrived. Using the earthquake data shown in the figure, what is the lag time? Form a general conclusion about the relationship between lag times and locations of earthquakes. Figure 19-3 A seismograph in northern Canada made this record of seismic waves from an earth-quake in Mexico. The first vibrations, P waves, arrived 11 minutes after the quake, but the slower S waves took 20 minutes to make the journey.arrow_forwardOver the entire Earth, there are 60,000 km of active rift zones, with average separation rates of 5 m/ century. How much area of new ocean crust is created each year over the entire planet? (This area is approximately equal to the amount of ocean crust that is subducted since the total area of the oceans remains about the same.)arrow_forward
- The Hawaiian-Emperor chain of undersea volcanoes is about 7500 km long, and the Pacific plate is moving 9.2 cm a year. How old is the oldest detectable volcano in the chain? What has happened to older volcanoes in the chain?arrow_forwardLook at the hemispheres of Earth shown on the two pages of The Active Earth. Name a folded mountain range. Describe the locations of one subduction zone and one midocean rise.arrow_forwardWhat characteristics must Earths core have to generate a magnetic field?arrow_forward
- What is the volume of new oceanic basalt added to Earth’s crust each year? Assume that the thickness of the new crust is 5 km, that there are 60,000 km of rifts, and that the average speed of plate motion is 4 cm/y. What fraction of Earth’s entire volume does this annual addition of new material represent?arrow_forwardWhat Is KMT And What Are Its Assumptions?arrow_forwardSeismic migration can be best described asa. Converting the seismic section from time to depthb. Adjusting the reflection time based on the hyperbolic travel timec. Stacking the tracesd. Putting seismic reflectors in their correct locationarrow_forward
- Foundations of Astronomy (MindTap Course List)PhysicsISBN:9781337399920Author:Michael A. Seeds, Dana BackmanPublisher:Cengage LearningAstronomyPhysicsISBN:9781938168284Author:Andrew Fraknoi; David Morrison; Sidney C. WolffPublisher:OpenStax
- Horizons: Exploring the Universe (MindTap Course ...PhysicsISBN:9781305960961Author:Michael A. Seeds, Dana BackmanPublisher:Cengage LearningStars and Galaxies (MindTap Course List)PhysicsISBN:9781337399944Author:Michael A. SeedsPublisher:Cengage Learning