In the Earth, P waves travel at speeds from about 6 km (3.7 miles) per second in surface rock to about 10.4 km (6.5 miles) per second near the Earth’s core some
2,900 km (1,800 miles) below the surface
. As the waves enter the core, the velocity drops to about 8 km (5 miles) per second.
Where do seismic waves travel lowest?
Surface waves
travel along the ground outward from an earthquake’s epicenter. Surface waves are the slowest of all seismic waves. They travel at 2.5 km (1.5 miles) per second. There are two types of surface waves.
Which seismic waves travel the farthest?
The
surface waves
are generally the largest recorded from an earthquake. Body waves in the earth’s interior lose their amplitude rapidly as they get farther from the earthquake because they spread out inside the volume of the earth.
Do seismic waves decrease with depth?
Frequency diminishes with depth
because high-frequency waves are attenuated as they pass through the Earth, so that only low-frequency waves survive to depth in the Earth. Velocity of seismic waves increases with depth because the rocks through which they pass become more compacted and thus more dense with depth.
Do you feel earthquakes underground?
The epicentre is on the surface by definition, but the hypocentre is certainly below the surface.
Earthquakes are definitely felt in basements
.
What seismic waves stay on surface?
S waves are called secondary waves because they always arrive after P waves at seismic recording stations. Unlike P waves, S waves can travel only through solid materials. After both P and S waves have moved through the body of Earth, they are followed by
surface waves
, which travel along Earth’s surface.
When the seismic waves travel deeper into the crust?
Answer. Answer: 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 does seismic velocity increase with depth?
Seismic velocities tend to gradually increase with depth in the mantle
due to the increasing pressure, and therefore density, with depth
. However, seismic waves recorded at distances corresponding to depths of around 100 km to 250 km arrive later than expected indicating a zone of low seismic wave velocity.
How or where do seismic waves travel?
Types of Seismic Waves
Body waves can travel through the Earth’s inner layers, but surface waves can only move along the surface of the planet like ripples on water
. Earthquakes send out seismic energy as both body and surface waves.
How long does it take seismic waves to travel?
The velocity depends on which type of wave and what part of the earth you are in – crust, mantle, core. But my rule of thumb for velocities of seismic waves that travel some distance from the epicenter is about
8 km/second (or 8000 meters/second) for a P wave, and 5 km/second for an S wave
.
Why do earthquake waves travel faster through the deep mantle than through the lithosphere?
Why do earthquake waves travel faster through the deep mantle than through the lithosphere? a.
The deep mantle is hotter than the lithosphere
.
Do seismic waves travel faster in denser mediums?
Seismic waves travel more quickly through denser materials
and therefore generally travel more quickly with depth. Anomalously hot areas slow down seismic waves. Seismic waves move more slowly through a liquid than a solid.
What happens to seismic waves as they travel away from the focus?
As seismic waves travel away from the focus they
decrease in energy & intensity
. Why does the most damage occur close to the fault? The most damage occurs close to the fault because it is where the greatest amount of energy is found.
What is the effect of seismic waves on the Earth?
Seismic shaking during earthquakes is a potent reminder of the active tectonic processes shaping the surface of the Earth. In addition to their impacts on the surface, seismic waves can have an effect at depth,
altering the conditions on fault zones and triggering other earthquakes
.
Why can’t you feel an earthquake in a cave?
The complexity of the cave seems to be a very important factor with regard to issues of cave passage “stability”
. A small tube-like passage appears to be a relatively safe location that doesn’t tend to collapse or sustain much, if any, damage from earthquake shaking.
What happens to a subway during an earthquake?
Since underground structures move with surrounding soil,
the Metro Rail system would not sustain damage or suspend train service in a low-magnitude earthquake
. If a stronger earthquake were to occur, the Metro system would likely only experience minor, repairable damage.
Can lightning cause earthquakes?
(Image credit: Tony Shinbrot.)
Mysterious flashes of lightning sometimes herald earthquakes
, and now scientists may have discovered why: Shifting grains surrounding faults in the Earth may generate an electric charge. This strange flickering, known as earthquake lights, can occur before or during quakes.
Why do seismic waves bend as they travel through the Earth?
The waves are refracted as they travel through the Earth
due to a change in density of the medium
. This causes the waves to travel in curved paths. When the waves cross the boundary between two different layers, there is a sudden change in direction due to refraction.
What seismic wave can travel through the Earth’s core?
P-waves speed up again through the inner core and
S-waves
also travel through it, suggesting that the inner core is composed of solid iron and nickel. 3.
Which seismic wave Cannot penetrate core?
The seismic waves that get refracted and cannot pass through the core of the Earth are:
S-waves
.
What do seismic waves carry?
Seismic waves carry
the energy of an earthquake away from the focus, through Earth’s interior, and across the surface
.
How do seismic waves work?
When an earthquake occurs, rocks at a fault line slip or break, and two sections of Earth’s crust physically move relative to one another. That movement releases energy, and
two types of seismic waves radiate outward from the earthquake through Earth’s interior and along its surface
.
Which seismic wave can penetrate core but refracts?
10. Which seismic wave can penetrate the core but refracts?
P waves
also refracts but is able to penetrate the core.
