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Ancient Earth

Atlantis Notes:

The Formation of Atlantis

From Impediment to Subduction
to the Spread of Boundary Damage

The following graphics show a sequence of events over the last 50-60 million years. Accurate dates are one of the hardest things to achieve here. The sequence, however, is very straightforward.

First, we start with an abrupt shift in the Africa Euler pole with respect to Eurasia. The cause of this shift is still under investigation, but there are a limited number of possible causes for all past Euler pole shifts. The end result of this shift was stress on the "Azores" triple junction resulting in folding roughly perpendicular to the Africa-Eurasia boundary. The Azores archipelago, of course, is millions of years in the future.

The red arrows are motions of each plate relative to the MAR. The black arrows are motions of the Africa plate with respect to the Eurasia (except for the one arrow countering the MAR increase of the Africa plate in the first illustration).

The northward movement of Africa that had been going on for roughly 180 million years results in continued subduction along most of the plate boundary with Eurasia. At the area of boundary damage, subduction has ceased. The damage is an effective impediment to subduction locally. Crustal folding continues for 15-20 million years.

At some point, folding can no longer proceed against the original area of damage. The folding has reached a limit. The northward movement of Africa, locally, is now deflected.

Imagine two pieces of paper, one sliding underneath the other. If a thumbtack is pushed through both papers near their "boundary," but to the left side ("West"), then any further forward movement of the "subducted" piece of paper would result in rotation around the thumbtack axis. Such a simple illustration is incomplete, of course. Many more things were happening to Africa (especially along all of its other borders).

This is the start of the Terceira Ridge which is part of the effective image of rotation across the entire length of the Africa-Eurasia boundary — divergence in the West (Terceira Ridge) and increasing convergence toward the East.

Geology of Atlantis about 36 Mya.

With a cease of the northward movement of Africa (with respect to Eurasia) at the original area of damage, the formative pressure is off of the area of fresh uplift. The effectively lateral movement around the area of damage, gradually weakens the new island. Perhaps millions of years later, it starts to collapse or depress from the crustal "stretching."

Convergence between the area of damage and the Gibraltar area results in a spreading of the area of damage along the plate boundary. The reason for the spread of damage is simple. Subduction next to an area of blockage is going to experience some difficulty because of that adjacent blockage. Like a zipper closing, the damage spread toward Gibraltar and led to its eventual closure approximately 5.9 Mya. This was the Messinian Salinity Crisis which lasted approximately 700,000 years.

It had always puzzled the author how Plato's Atlantis had possessed elephants. With this it's easy to see that elephants from Europe and Africa merely walked across the Atlantis peninsula. They had perhaps up to 700,000 years with which to make the passage. Then Atlantis became an island again as crustal slumping accelerated, returning the uplifted land to the ocean floor where it was originally intended to be.

Geology of Atlantis about 5.9 Mya.

A new book about Atlantis is currently in the works — Mission: Atlantis.


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