Because it has been proven that the outer layer is made of liquid and secondary waves do not move through liquid ^~^
Chat with our AI personalities
S waves cannot travel through the outer core because they can only travel through solids, and the outer core is liquid.
s waves cant travel through it
They go faster through the inner core than the liquid outer core.
Firstly, there are 3 types of seismic waves. Long Waves, Primary Waves(Longitudinal) and Secondary Waves(Transverse). Long Waves travel quickly along the Earth's crust, the thin outer layer. Primary Waves are longitudinal waves, they can travel both through solids andliquids, so they travel through the crust, the mantle, and the outer core (note that they refract through each layer, as each layer has a different density. Secondary Waves are transverse waves, they can only travel through solids, so they go through the inner and outer mantles, and curve away from the cores.
While S waves (shear waves) can travel through earth's solid inner core, they cannot travel through earth's liquid outer core, which surrounds the inner core.So, unless the S waves originated inside the inner core (which seems unlikely) there are no S waves traveling through earth's inner core.