Step-by-step explanation:
At the station, the P-waves arrives first before the S -waves. These two waves are together known as the body-waves. Body waves permeates through the earth unlike the surface waves that moves on the earth surface.
P waves are typically known as the primary waves. They are longitudinal waves as they travel parallel to the source of their propagation. Therefore, they have the highest wave velocity and can travel through any type of medium. By this their longitudinal compressional ability which applies a force in the direction of their propagation, a series of rarefaction and compression occurs along their path and makes them easier to disseminate.
S waves are secondary or shear waves. They are transversal waves because they move perpendicularly to their source. To transmit this kind of wave would be very difficult. Without a body shearing, S - waves cannot propagate. It is therefore, more difficult to transmit the energy in this regard.
The nature of S -waves makes it difficult to be transmitted when compared to P - waves. This will in turn reduce its frequency, and hence its velocity.