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The Atlantic Ocean is mainly formed by two gigantic convection rolls. In between them, the Mid-Atlantic Ridge actively forms new oceanic crust out of basalt. The North and South Atlantic look similar, and here we will have a look at both the similarities and the differences. There are four main sections with 32° interval from north to south.

Within part 1, the ridge and rolls division line are unified along Reykjanes Ridge (offset by 1.5° west), but sways east of the convection rolls division line south of the Reykjanes Ridge. Both ridge and convection rolls division line intersect each other at 32°N. The reason is that at 32°N the convection rolls are oriented directly NS, so it becomes a latitude of division between different sections of the ridge.

Within part 2, the ridge sways slightly west of the convection rolls division line. A part of Africa still sticks out into the Eastern Convection Roll Area within that section.

Within part 3, the ridge is almost directly oriented NS, giving the South Atlantic part a slightly different appearance than the North Atlantic. The section includes the highland of Southern Africa, marked by the outer limits of the convection roll. At 32°S, the eastern division line crosses the coastline.

Within part 4, the Ridge makes a turn towards east. The arc shaped ridge makes the turn around the convection rolls division line, also marking the end of the real Mid-Atlantic Ridge.

It is notable that the western foothold point of Greenland at 64°N is of the same nature as the eastern foothold point of Africa at 32°S.

In this way, we get a glimpse of the main constraints forming the Atlantic Ocean during the present era. A NS-axis can be marked from equator to Iceland and through the South Atlantic. This NS-axis is the same as can be found when examining the details of Icelandic geology, both volcanic activity and the Icelandic Plateau.

‘Searching for something and not finding it is also science.’ James Cook sailed all over the Pacific searching for a continent that should be there. After looking at how land is distributed over the equatorial line, one should expect to find a continent in the middle of the Pacific Ocean.

All the land masses cover 30°, except Africa, but the distance from west coast to Great Rift Valley is 30°. So when looking at this picture, the match between model and reality is striking.

The division lines affect the surface of the Earth quite clearly, but nowhere as securely as along equator. At equator, points of restriction are created, due to special circumstances. The Coriolis Effect shifts from leading a trajectory to the right within northern hemisphere to leading to the left in the southern hemisphere. This, along with the fact that the equatorial plane has the greates centrifugal effect, coinciding with the convectional effect, makes the distribution of land mass so special. You can therefore call the main points on equator ‘equatorial points of constraint’.

After exploring three sides of the Earth, more and less alike, the fourth side looks totally different. The Central Pacific Ocean provides very few clues about what is found underneath, with the main exception of Hawaii.

If there was a continent there, like Africa, South America or Indonesia, we would have analyzed that consistency a long time ago. This one exception leads to the fact that we do not seem to consider the consistency between the three equatorial continents at all! But considering that Hawaii exist due to the proximity with main division line between convection rolls, the picture becomes clearer. Hawaii itself is offset from the main lower mantle convection rolls division line by 3°, but the chain of islands then drifts obliquely over it.

We can then have a quick look at the ´four side pattern´:

So if we have an imaginary place in the middle of the Pacific, where we might expect to find a continent, do we then start to think differently about it?

The similarity between Central Africa, Amazon and Indonesia is quite striking. The three areas are found at equator, span 30°, and are found with 60° interval. Also, volcanic and tectonic activity is found in context with the relevant mantle convection division lines, marking the large scale polygon.

The volcanic activity in eastern Africa is related to the Great Rift Valley, which is closely related to the tectonics formed by the east corner of the polygon of Central Africa.

The Amazon area is mostly found within a large polygon marked by the division lines of each side of a single convection roll of lower mantle. The main hub of downwelling forms the esturary of the Amazon River, the largest river in the world. At the other side of the continent, the division line (wide red) between convection rolls does cross the Andes Mountains under the volcano Tuguruahua.

The exact 30° span along equator from the trench in the east to the estuary in the west is an outstanding manifestation of the predicted interval between convection rolls of the lower mantle.