Table of Contents
- 1 Where is the shadow zone located?
- 2 Why is there ap wave shadow zone?
- 3 What does the shadow zone reveal about the state of matter in Earth’s interior?
- 4 What does S wave shadow zone indicate?
- 5 Can S-waves pass through the stiffer mantle?
- 6 Why do P waves occur on the other side of the Earth and S-waves do not?
- 7 Which pressure can be found in the stiffer mantle?
- 8 Which is the best definition of a shadow zone?
- 9 Where is the Shadow Zone of an earthquake?
Where is the shadow zone located?
The shadow zone is the area of the earth from angular distances of 104 to 140 degrees from a given earthquake that does not receive any direct P waves. The shadow zone results from S waves being stopped entirely by the liquid core and P waves being bent (refracted) by the liquid core.
Why is there ap wave shadow zone?
P waves do travel through liquids, so they can make it through the liquid part of the core. Because of the refraction that takes place at the CMB, waves that travel through the core are bent away from the surface, and this creates a P wave shadow zone on either side, from 103° to 150°.
What does the shadow zone reveal about the state of matter in Earth’s interior?
Seismic shadow zones have taught us much about the inside of the earth. This shows how P waves travel through solids and liquids, but S waves are stopped by the liquid outer core. The wave properties of light are used as an analogy to help us understand seismic-wave behavior.
Which shadow zone is larger?
P-wave shadow zone
the P-wave shadow zone is larger than the S-wave shadow zone.
What is difference between P and S-waves?
Body waves are the waves that can travel through the layers of the earth….Difference between s waves and p waves.
| P waves | S waves |
|---|---|
| The first wave to hit seismographs | Second waves to hit seismographs |
| They are compression waves | They are shear waves |
| Can move through solids and liquids | Can only move through solids |
What does S wave shadow zone indicate?
The S wave shadow zone is the area of the Earth’s surface where S waves are not detected following an earthquake. This shadow zone has led geologists to a model of the Earth with a solid mantle and a liquid core. Geologists have been able to calculate the size of the liquid core from these measurements.
Can S-waves pass through the stiffer mantle?
S-waves can travel only through solids, because only solids have rigidity. Because the earth’s mantle becomes more rigid as its depth below the asthenosphere increases, S-waves travel faster as they go deeper in the mantle.
Why do P waves occur on the other side of the Earth and S-waves do not?
P-waves are compression waves that apply a force in the direction of propagation. As the interior of the Earth is almost incompressible, P-waves transmit their energy quite easily through the medium and thus travel quickly. The energy is thus less easily transmitted through the medium, and S-waves are slower.
How do P waves and S waves move?
P waves can travel through solids, liquids, and even gases. S waves shake the ground in a shearing, or crosswise, motion that is perpendicular to the direction of travel. These are the shake waves that move the ground up and down or from side to side.
Why do P-waves occur on the other side of the Earth and S waves do not?
Which pressure can be found in the stiffer mantle?
Which combination of temperature and pressure is inferred to occur within Earth’s stiffer mantle? 3,500 degrees C and 0.4 million atmospheres.
Which is the best definition of a shadow zone?
Seismic Shadow Zones: P wave. The shadow zone is the area of the earth from angular distances of 104 to 140 degrees from a given earthquake that does not receive any direct P waves.
Where is the Shadow Zone of an earthquake?
A seismic shadow zone is an area of the Earth’s surface where seismographs can only barely detect an earthquake after its seismic waves have passed through the Earth.
When was the Shadow Zone of the Earth discovered?
Through measuring how P and S waves travel through the earth and out the other side, a seismic wave shadow zone was discovered in about 1910. From the lack of S waves and a great slowing of the P wave velocity (by about 40%) it was deduced that the outer core is made of liquid. The shadow zone also defined the diameter of the core.
How are S waves stopped in the Shadow Zone?
The different phases show how the initial P wave changes when encountering boundaries in the Earth. The shadow zone results from S waves being stopped entirely by the liquid core. Three different S-wave phases show how the initial S wave is stopped (damped), or how it changes when encountering boundaries in the Earth.