Question

what do you mean by shadow zone of the earthquake

Answer 1

There are two types of Shadow zones: one for P waves and one for S waves

See attached file

These are the places where no direct seismic waves are received after an earthquake.

This happens because of the liquid outer core. It does not allow S-waves to pass through and refract P-waves, twice.

Please note- The locations shown in the image will change with change in epicenter. But they will form at the same angles with respect to the new epicenter, i.e. P wave shadows between 105-140 degree, both sides; S wave shadow from 105 of one side to 105 of the other.