January 8, 2022
The existence of a shadow zone for Primary seismic waves (P-waves) and Secondary seismic waves (S-waves) at the opposite side of the earthquakes suggests that there is some faculty inside the Earth that allows this to happen. According to the current beliefs, the work of Richard Dixon Oldham allegedly proved the existence of a “dense core” inside the Earth. Later on, Sir Harold Jeffreys allegedly proved that the outer core is liquid. However, Inge Lehmann suggested the existence of a solid inner core in order to comply with some theoretical considerations.
In this paper, we will analyze if the refraction of seismic waves gives evidence for a liquid core, and we will conclude that another, much simpler layout of the Earth’s “internals” explains as well the refraction analysis of earthquakes.