In 1962 Harry Hess made a big contribution by showing the importance of mid ocean ridges in Earth’s geology. At the same time he put forward his idea about convection current system:
Hess, Harry. „History of Ocean Basins.“ Petrologic studies: a volume in honor of A. F. Buddington Geological Society of America (1962): 599-620.
This picture drawn by Harry Hess, if taken accurately, gives 8 large convection cells around the globe.
In 1971 Uwe Walzer wrote an article showing that convection cells within the earth must be as regular as possible. He explained the preconditions for for this conclusion and searched systematically for a solution.
WALZER, UWE. 1971. Pure and Applied Geophysics Volume 87, Number 1, 73-92, DOI: 10.1007/BF00878910
This drawing by Waltzer has 14 large mantle currents.
With additional information available since the times around 1960-1970, I found the large convection cells to be 12, not 8 or 14! And with the help of a few laws of physics, geology of Iceland suddenly seems so much more simple to understand!
The logo of this site shows the slightly different pattern:
With the 240 smaller cells side by side under the crust and by referring to the Coriolis Effect (different angular velocity for each latitude), the 3D model was completed.
It can be used right away to answer a million questions!