Another example of how the topography follows the division lines of convection rolls along equator is Indonesia. It spans 30° from east to west, just like South America. Also, the two points of east and west have exactly the correct position as compared to S-America. We find steps of 30° around the world!
So this pattern is obvious. The up-welling line is found at the western point of the 30° string, extending farther to the south where you find Krakatoa, one of the most famous volcanoes in the world. Therefore, behind the trench and relevant geology, there are geophysical preconditions we should look into.
The string length along equator over S-America and Indonesia is exactly the same. Both span 30° out of the 360° of the whole of equator. Besides that, the two strings are found exactly opposite to each other as shown in the drawing above. It should be enough just to point this out, so everyone can see that this can be no coincidence. This distribution is also consistent with the convection rolls model, with the width of the convection rolls underneath being the same as the height. By noticing this, we add to our possibilities to understand the functions of the Earth, on which we live.