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What is the form of energy released when a fault moves?
As discussed in Lesson 5, earthquakes occur when elastic energy is accumulated slowly within the Earth’s crust as a result of plate motions and then released suddenly at fractures in the crust called faults. The released energy travels in the form of waves called seismic waves.
What is the energy stored along faults?
When a rupture occurs along a fault, the strain energy stored on either side of the fault is released in the form of seismic waves and heat. These seismic waves propagate away from the ruptured fault zone and through the geologic layers of rock and soil.
What kind of movement is produced by S waves?
S waves produce vertical and horizontal motion in the ground surface. Particle motion consists of alternating transverse motion. Particle motion is perpendicular to the direction of propagation (transverse).
What type of energy waves are released during an earthquake?
Types of Seismic Waves The two main types of waves are body waves and surface 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.
What are two characteristics of P waves?
Although liquids and gases have zero rigidity, they have compressibility, which enables them to transmit P-waves. Sound waves are P-waves moving through the air….P-Waves.
| P-waves travel through materials with rigidity and/or compressiblity, and density | |
|---|---|
| greater compressibility | faster P-waves |
| greater density | slower P-waves |
How do we know if a fault is active or not?
Faults are commonly considered to be active if there has been movement observed or evidence of seismic activity during the last 10,000 years. Active faulting is considered to be a geologic hazard and related to earthquakes as a cause.
What are the three types of faults?
There are three main types of fault which can cause earthquakes: normal, reverse (thrust) and strike-slip. Figure 1 shows the types of faults that can cause earthquakes. Figures 2 and 3 show the location of large earthquakes over the past few decades.
What is the difference between S waves and P waves?
P waves are recorded earlier than S waves, because they travel at a higher velocity. P waves can travel through liquid and solids and gases, while S waves only travel through solids. Scientists use this information to help them determine the structure of Earth.
What are 4 types of seismic waves?
Seismic Wave Motions—4 waves animated
- Body Waves – Primary (P) & Secondary (S) Waves.
- Surface Waves – Rayleigh & Love Waves.
Which is faster S or P waves?
P waves travel fastest and are the first to arrive from the earthquake. In S or shear waves, rock oscillates perpendicular to the direction of wave propagation. In rock, S waves generally travel about 60% the speed of P waves, and the S wave always arrives after the P wave.
Where do P waves travel the fastest?
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.