Why is the surface wave the most dangerous and the most destructive?
Surface waves – By a property called dispersion, surface waves of different wave lengths travel at different velocities. It is the surface waves which cause most property damage because surface waves produce more ground movement and travel more slowly, so they take longer to pass.
What is the fastest surface wave?
Love wave
Which set of waves 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 is PS and L waves?
In P or compressional waves, the vibration of the rock is in the direction of propagation. P waves travel fastest and are the first to arrive from the earthquake. 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.
Which is faster S or P wave?
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. The energy is thus less easily transmitted through the medium, and S-waves are slower.
Why are there no P waves or S waves?
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 do P waves have a 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 P wave stand for?
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 do abnormal P waves indicate?
The Abnormal P wave If the p-wave is enlarged, the atria are enlarged. If the P wave is inverted, it is most likely an ectopic atrial rhythm not originating from the sinus node. Altered P wave morphology is seen in left or right atrial enlargement.
What is a normal P wave?
The normal P wave morphology is upright in leads I, II, and aVF, but it is inverted in lead aVR. The P wave is typically biphasic in lead V1 (positive-negative), but when the negative terminal component of the P wave exceeds 0.04 seconds in duration (equivalent to one small box), it is abnormal.
What does a normal P wave look like?
In a normal EKG, the P-wave precedes the QRS complex. It looks like a small bump upwards from the baseline. The amplitude is normally 0.05 to 0.25mV (0.5 to 2.5 small boxes). Normal duration is 0.06-0.11 seconds (1.5 to 2.75 small boxes).
What does a long P wave mean?
P wave duration is a marker of atrial conduction derived from ECG. Normal P wave can be considered to be less than 110 ms [12–14]. Prolonged P wave duration signifies conduction delay between right and left atrium due to impulse slowing or blockage, probably most often but not exclusively in the Bachmann bundle.
What is the Q wave?
By definition, a Q wave on the electrocardiogram (ECG) is an initially negative deflection of the QRS complex. Technically, a Q wave indicates that the net direction of early ventricular depolarization (QRS) electrical forces projects toward the negative pole of the lead axis in question.