The Convection Rolls Model has been used to explain a myriad of geological features. The starting point is easy to derive, because the layers of Earth have a regular pattern, and Rayleigh-Bénard type of convection rolls fit precisely into it.
Layers of Earth and Rayleigh-Bénard convection rolls inserted.
The convection rolls are affected by the rotation of the Earth, and the same proportions prevail farther north and south within the rotational plane. The height and width of the mantle convection rolls therefore adhere to the physics of Rayleigh-Bénard convection all over the globe.
Therefore, it was possible to derive the comprehensive or global convection rolls model, starting from the obvious match within the equatorial plane.
The match shown above is mathematical, to show that the intersection zones are really intersections between main layers. At equator, the convection rolls tend to be arranged directly above each other.
This drawing shows how the convection rolls are arranged directly above each other. It also shows secondary convection rolls within the lower mantle. The Lehmann layer of the core is omitted here. The system can then be traced northwards and southwards, and the global system derived, which is described here.
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