GEOLOGY

Detailed explanation-1: -S-waves do not enter the core because they cannot travel through solids. Seismologists have reasoned that Earth’s outer core must be liquid based on the disappearance of S-waves. Studies of how waves reflect deep inside Earth show that Earth’s inner core is solid. The P-wave shadow zone does not receive direct P-waves.

Detailed explanation-2: -S-waves are shear waves, which move particles perpendicular to their direction of propagation. They can propagate through solid rocks because these rocks have enough shear strength.

Detailed explanation-3: -Figure 19.2b: S-waves do not travel through the outer core, creating an even bigger shadow zone for S-waves. The fact that S-waves do not travel through the outer core suggests that the latter is liquid.

Detailed explanation-4: -S-waves passing from the mantle to the core are absorbed because shear waves cannot be transmitted through liquids. This is evidence that the outer core does not behave like a solid substance. S-waves are not transmitted through the liquid outer core.

Detailed explanation-5: -S-waves cannot travel through liquids. When they reach the surface they cause horizontal shaking. Liquids don’t have any shear strength and so a shear wave cannot propagate through a liquid. Think of a solid material, like a rock.