What is P wave S wave and L wave?

There are two types of seismic waves, primary waves and secondary waves. Primary waves, also known as P waves or pressure waves, are longitudinal compression waves similar to the motion of a slinky (SF Fig. 7.1 A). Secondary waves, or S waves, are slower than P waves.

What are L waves in an earthquake?

Surface Waves (L-waves)



These are waves of long wavelength, restricted to the skin of the Earth’s crust, and lead to most of the earthquake’s structural damage. The surface waves are the last to arrive on the seismograph.

What are the 4 types of earthquake waves?

Love Waves—surface waves that move parallel to the Earth’s surface and perpendicular to the direction of wave propagation..

• P-wave Motion. P-wave:the primary body wave; the first seismic wave detected by seismographs; able to move through both liquid and solid rock. …
• S-wave Motion. …
• Rayleigh-wave Motion. …
• Love-wave Motion.

What are P waves?

A P wave, or compressional wave, is a seismic body wave that shakes the ground back and forth in the same direction and the opposite direction as the direction the wave is moving.

What does l wave stand for?

The different S waves arrive after the P waves. The slowest (and latest to arrive on seismograms) are surface waves, such as the L wave. L waves are named for the Cambridge mathematician A.E.H. Love who first described them. The surface waves are generally the largest recorded from an earthquake.

What does L in L waves stand for?

A. S. Adikesavan. Jul 20, 2016. P, S and L waves refer to Primary, Secondary and Longitudinal waves. L is also the first letter in Love waves.

What does the S wave do?

In an S wave, the rock particles slide past one another, undergoing shear — so an S wave is also called a shear wave. You can make shear waves by, for example, tying a rope to a tree and shaking the free end of the rope up and down or side-to-side. The waves themselves will travel forward, toward the tree.

What type of wave is P wave?

compressional waves

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.

How do you find the P wave and S wave?

https://youtu.be/
If the seismic wave arrival time.

How are S waves and P waves similar?

P waves and S waves are alike because they are both types of seismic waves produced by the sharp movement of rocks within the earth.

What does S mean in S waves?

The S in S-waves stands for secondary, because they are the second-fastest seismic waves and the second type to be detected once an earthquake has occurred.

What does P in a P wave mean?

Answer. The P wave represents atrial depolarization. The normal P wave morphology is upright in leads I, II, and aVF, but it is inverted in lead aVR.

What does P in P wave stand for?

primary

Compressional waves are also called P-Waves, (P stands for “primary“) because they are always the first to arrive. They gave us the first jolt last Friday. Shear waves propagate more slowly through the Earth than compressional waves and arrive second, hence their name S- or secondary waves.

What are P and S wave shadow zones?

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.

What does the 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. From the diagram, we can see the region where S waves are not detected.

What is the P wave shadow zone and what causes it quizlet?

The P-wave shadow zone is the result of the refraction effects P-waves go through as they travel deep inside the Earth. It extends from 105 to 142 degrees.

Why do you think only P waves can be observed in the S wave shadow zone?

This indicates that P-waves slow down in the outer core, suggesting that this layer has a significantly different composition from the mantle and may actually be liquid. This bending in the outer core creates a P-wave shadow zone where no P-waves are detected.

What happens to the P and S waves as they travel inside 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.

How P and S waves are used to describe the interior of the Earth?

Seismic waves tell us that the Earth’s interior consists of a series of concentric shells, with a thin outer crust, a mantle, a liquid outer core, and a solid inner core. P waves, meaning primary waves, travel fastest and thus arrive first at seismic stations. The S, or secondary, waves arrive after the P waves.

Why are there no P waves or S waves received in the P wave?

Why are there no P waves or S waves received in the P wave shadow zone? P waves are absorbed and S waves are refracted by Earth’s outer core.

What is the difference between P waves and S waves based on their movement speed and capacity to move through a medium?

P-waves and S-waves are body waves that propagate through the planet. P-waves travel 60% faster than S-waves on average because the interior of the Earth does not react the same way to both of them. P-waves are compression waves that apply a force in the direction of propagation.

Why does the time between the arrival of the P wave and S wave become greater?

As the P and S waves travel out from an earthquake the P waves get progressively farther ahead of the S waves. Therefore, the farther a seismic recording station is from the earthquake epicenter the greater will be the difference in time of arrival between the P and S wave.

Why do P waves slow down in a liquid?

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?

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. The higher density reduces the speed of seismic waves.

What would S waves do when they enter the asthenosphere?

The velocity of s waves going through the asthenosphere decreases, which tells us that peridotite contains a few percent partial melt, but not enough to stop s waves. What is the composition of the mantle? One of Earth’s compositional layers.