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The two parts of the Atlantic Ocean are clearly divided along equator. The central point can be defined, because the Atlantic is exactly 60° wide along equator from Amazon Esturary to the West Coast of Africa. The equatorial part of the Mid-Atlantic Ridge then reaches equadistant to east and west, accurately 9° to each direction. That is equavalent to 6 convection rolls, as each convection roll spans 1.5° from east to west.

The two ridges are then formed differently, one following the main swaying trend of convection rolls (North Atlantic) and the other follows the NS-trend of the convection rolls system (South Atlantic). Similar difference can be observed on small scale in Iceland, where in the southern half of Iceland the alignment is NE-SW, and then shifts to NS-alignment in the northern half. In turn, we have to analyze why nature makes these ´different choices´, and likewise we should try to explain why we find symmetry of nature as shown here.

The large scale convection rolls of lower mantle are not drawn here. They span 30° from east to west, so the thin yellow line represents the pair of lower mantle convection rolls along equator.

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.