I am a geologist, graduated from the University of Iceland, and taught geology for a few years. I have gained some knowledge about Earth's inner structure, so I provide this website as my contribution to answer one of the greatest questions remaining within the realm of geoscience. Experiments show that the mantle should form convection rolls when close to the melting point. I took this literally, and calculated the dimensions and shape of these mantle convection rolls. Then I compare that model with the surface. This makes it possible to provide many interesting examples about geology found on my blog.
The pattern of land distribution along equador is one of the characteristics making our globe beautiful seen from space. Pointing the regularity out makes us think as well as feel. This circle spanning 30° along along 0° of latitude tells a story. A string is drawn through the circle, showing how the Amazon area is approximately aligned.
The circle of Amazon.
The forces of tectonic drift have been affecting South America quite strongly. According to the model of convection rolls, the Amazon estuary is located at a divisional line/point of downwelling between two large scale convection rolls of lower mantle. The span of the continent is exactly 30° along equator from coast to coast. This provides some constrains on the tectonic drift, causing South America to rotate. This circle represents one aspect of these present movements.
The Aleutean Islands form an arc as the Pacific Plate drifts underneath the North American Plate. It is tempting to study a bit closer, because it seems like a semi-circle with a string from east to west. Let us follow the islands, connecting them with a line, and see what we get:
The area of Kamchatka is geologically extremely important, becauase in those areas the North American Tectonic Plate meets the Eaurasian Plate. A main division line of the model used here does cross the peninsulas there.
To introduce the model of convection rolls and how it explains the existence and distribution of geothermal resources in Iceland, I take part in the World Geothermal Congress held in Reykjavik this year (2021). The model should better have been developed in the nineteenth century when it was realized that land mass is regularly distributed along equator, and that must be for a reason. Someone should have considered that the span of the Atlantic Ocean and the Indian Ocean of 60° represented two large convecction cells, and the mainland of S-America, Africa and Indonesia span 30°, did show the location of a single large scale convection cell underneath. But no one did, so this became a debate finding place within the twentyfirst century! Harry Hess https://en.wikipedia.org/wiki/Harry_Hammond_Hess was on the correct track in 1962 with the article ´History of Ocean Basins´. Further development effort by the scientific community of his theory would have made this website obsolete. But my video about geothermal resources is found here, meant to bring us all one step closer to the ‘correct track’ again: https://wgc2020-virtual2.velkomin.is/login?redirect=/event/13040
Realizing that convection takes place within the mantle is easy and acknowledged by virtually everyone engaged in geoscience. The convection pattern, on the other hand, was a bit hard to derive. Now it has all been clarified and shown to everyone. The starting point is obvious enough to be 100% convincing, namely the fact that convection rolls with height to width ration 1:1 clearly fit exactly within the equatorial plane. The rest has to be found out, step by step, with the help of some knowledge about physics. You have to consider that the Earth rotates, that the mantle convects, and the constraints resulting from the geoid shape. Then you find out the exact dimensions, shape and location of the convection rolls within the Earth.
Tectonic drift has to be powered with convection currents. The currents do not work against each other due to slip and no-slip conditions. When a tectonic plate has started drifting into a certain directions, those convection rolls rolling with it also connect with it firmly, but those rolling the opposite way loose the grip. This is due to the fact that the mantle is very close to melting point, so extra friction causes melting, but less friction causes solidation.
Slip and No-slip resulting in tectonic drift.
The large scale and small scale convection rolls then work together according to this picture:
Main points of main convection rolls division lines.
The small convection rolls found below the tectonic rolls therefore play a big role in inducing the tectonic drift.
We relate the Reykjanes Peninsula to the Reykjanes Ridge. It is so obvious that the peninsula is a continuation of this part of the huge Mid-Ocean Ridge of the Atlantic. But looking below the crust, things become somewhat different. The convection rolls of Reykjanes are subducted by the Kolbeinsey Ridge Convection Rolls, and therefore the magma now flowing as lava at Fagradalsfjall is not the same as that of the main part of the Reykjanes Ridge.
SS
The subduction can be shown graphically as here below:
The two systems of convection rolls intersect between 60.7°N and 67.3°N, and the northern rolls are found over the southern ones.
Magic Magma 