The direct P wave arrives first because its path is through the higher speed, dense rocks deeper in the earth. The PP (one bounce) and PPP (two bounces) waves travel more slowly than the direct P because they pass through shallower, lower velocity rocks.
The different S waves arrive after the P waves
.
Where do P and S waves travel faster?
Body waves travel through the body of a planet. Surface waves travel along the surface. There are two types of body waves:
P-waves travel fastest and through solids, liquids, and gases
; S-waves only travel through solids.
Are P or S waves more intense?
S waves are more dangerous than P waves
because they have greater amplitude and produce vertical and horizontal motion of the ground surface. The slowest waves, surface waves, arrive last.
What is the difference between P waves and S waves?
P waves can travel through any media (including liquid and gas), but S waves can only travel through solid media like rock.
P waves travel faster than S waves
. The difference in travel times can be used to determine the epicenter of the earthquake.
Why do S waves travel slower than P waves?
As the interior of the Earth is almost incompressible, P-waves transmit their energy quite easily through the medium and thus travel quickly. On the other hand,
S-waves are shear waves, which means that the motion of the medium is perpendicular to the direction of propagation of the wave
.
Why do P and S waves slow down in less dense material?
Seismic waves move more slowly through a liquid than a solid. Molten areas within the Earth slow down P waves and stop S waves because
their shearing motion cannot be transmitted through a liquid
. Partially molten areas may slow down the P waves and attenuate or weaken S waves.
Why do P waves travel faster in the mantle?
Sound waves are P-waves moving through the air.
Because the earth’s mantle becomes more rigid and compressible as the depth below the asthenosphere increases
, P-waves travel faster as they go deeper in the mantle. The density of the mantle also increases with depth below the asthenosphere.
Which seismic wave is the most powerful?
Seismic waves can be classified into two basic types: body waves which travel through the Earth and surface waves, which travel along the Earth’s surface. Those waves that are the most destructive are the
surface waves
which generally have the strongest vibration.
Why do P waves travel faster through denser material?
Generally,
p-wave velocity increases with depth and increases with increasing rigidity of a material
. Therefore p-waves travel fastest through the solid, iron inner core of Earth.
How fast do P and S waves travel?
Why do P waves arrive first? When an earthquake occurs, seismic waves, including P and S waves carry energy away from the hypocenter in all directions.
The P wave propagates with a velocity of about six kilometers per second in rock, while the S wave is slower at four kilometers per second
.
How do P and S waves travel?
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.
How P and S waves travel through the Earth?
The speed of P waves and S waves increases as they travel deeper into the Earth’s mantle .
They travel through the Earth in curved paths, but they change direction suddenly when they pass through the boundary between substances in different states
.
Which waves are fastest?
P-waves, or primary waves
, are the fastest moving type of wave and the first detected by seismographs. They are also called compressional or longitudinal waves, and push and pull the ground in the direction the wave is traveling.
Why do S wave travel in solid only?
S-waves are shear waves, which move particles perpendicular to their direction of propagation. They can propagate through solid rocks
because these rocks have enough shear strength
. The shear strength is one of the forces that hold the rock together, preventing it from falling into pieces. Liquids lack shear strength.
Which type of earthquake wave travel even slower than P waves and S waves?
S-waves
are transverse waves. Even though they are slower than P-waves, the S-waves move quickly. Typical S-wave propagation speeds are on the order of 1 to 8 km/sec.
Does the velocity of P waves and S waves increase or decrease with increased depth in the lithosphere?
The average density of continental lithosphere is (The average density of oceanic lithosphere is ). The increase in density leads to increases the velocity of P and S-waves. Hence, the velocity of P and S-waves
increases with depth in the lithosphere
.
What happens when seismic waves travel deeper?
Seismic stations located at increasing distances from the earthquake epicenter will record seismic waves that have traveled through increasing depths in the Earth. …
Molten areas within the Earth slow down P waves and stop S waves
because their shearing motion cannot be transmitted through a liquid.
Why do P waves travel faster through the lithosphere than the asthenosphere?
Sound waves are P-waves moving through the air.
Because the earth’s mantle becomes more rigid and compressible as the depth below the asthenosphere increases
, P-waves travel faster as they go deeper in the mantle. The density of the mantle also increases with depth below the asthenosphere.
Do P waves travel slower in liquid?
There are two types of waves that travel through the Earth: p-waves and s-waves.
P- waves are faster
and they can travel through both solids and liquids. S-waves are slower and cannot travel through liquids.
What type of wave is P wave?
P Waves. P waves are
compressional waves
that do not produce much damage. They can move through any type of material and travel at almost twice the speed of S waves.
Why do P waves bend when Travelling?
Figure 19.2a: P-waves generally bend outward as they travel through the mantle
due to the increased density of mantle rocks with depth
. When P-waves strike the outer core, however, they bend downward when traveling through the outer core and bend again when they leave.
Which set of waves are the S waves?
S-waves. S-waves, also known as secondary waves, shear waves or shaking waves, are
transverse waves
that travel slower than P-waves. In this case, particle motion is perpendicular to the direction of wave propagation.
