The origin of hotspot volcanoes has been debated, but the most popular theory suggests that plume-like structures bring hot mantle material all the way from the core-mantle boundary to the surface.
With images of the ultra-low velocity zone beneath Hawaii now in hand, the team can also gather rare physical evidence from what is likely the root of the plume feeding Hawaii.Their observation of dense, iron-rich rock beneath Hawaii would support surface observations.
More of the core-mantle boundary now needs to be imaged to understand if all surface hotspots have a pocket of dense material at the base.The team’s observations add to a growing body of evidence that Earth’s deep interior is just as variable as its surface.Eventually, they hope to map the geological landscape across the core-mantle boundary and understand its relationship with the dynamics and evolutionary history of our planet.
The graph of slopes from seismological P-waves showing their path of travel through the Earth’s interior should be concave with the actual path closely following the perimeter of the Earth.
The curvature is close enough to prevent the path of travel from descending very deep into the Earth’s interior, and also close enough to prevent the path of travel from ascending to where it would disappear.
The image in the article shows the P-wave path of travel as being convex.
As a P-wave descends into the interior, the closer to the surface of the Earth, mass through which the wave travels results in the wave traveling fastest.The slope of that line tilts forward causing a concave path of travel from the point of origin, from the epicenter.
The article should give you a better understanding of the affects of the interior of the Earth upon the path of travel of a P-wave.
I’m inclined to believe the reason scientists have this so wrong is that a correct interpretation of P-wave travel though the interior of the Earth proves the Earth is ‘hollow’.