Answer:
When an earthquake occurs the seismic waves (P and S waves) spread out in all directions through the Earth's interior. Seismic stations located at increasing distances from the earthquake epicenter will record seismic waves that have traveled through increasing depths in the Earth.
Seismic velocities depend on the material properties such as composition, mineral phase and packing structure, temperature, and pressure of the media through which seismic waves pass. 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. 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.
When seismic waves pass between geologic layers with contrasting seismic velocities (when any wave passes through media with distinctly differing velocities) reflections, refraction (bending), and the production of new wave phases (e.g., an S wave produced from a P wave) often result. Sudden jumps in seismic velocities across a boundary are known as seismic discontinuities.
Within the Earth, molten areas slow down P-waves and stop S-waves because shearing motion of the waves cannot be transmitted through a liquid.
Earthquake cause the seismic waves (P and S waves) that spread out in all directions even in the Earth's interior. Seismic waves move more slowly through a liquid than a solid.
Within the Earth, molten areas slow down P-waves and stop S-waves because shearing motion of the waves cannot be transmitted through a liquid.
Therefore, most of the S-waves of an earthquake disappear about a distance of 11,500 km from the epicenter.
To know more about S-waves,
https://brainly.com/question/19091422
