Nazca Plate and Wegener Crater

2.5      The link between Nazca Plate and Wegener Crater

The drifting of the Pacific and Nazca plates is continuous – the first emerges in the polar region and is subducted by the plates of Australia, Eurasia and North American Plate into the Aleutian Trench.

Meanwhile, the Nazca Plate diverges from the Pacific Plate and advances against the South American Plate, being subducted by this one.

Image: NAZCA PLATE, in Wikipedia, within a 5,000 km diameter circle

The movement of the magma underlying the Pacific Plate always occurs northwestward – but the crust that integrates the plate changes direction when it encounters sufficient resistance opposed to it.

The factor causing the occasional change of direction of this tectonic plate is the resistance offered by the large subplate generated by the Wegener Crater when it was blocked by the Eurasian plate.

The thicker, hardened crater surface subplate offered resistance when it collided with the tectonic plate in its path — and while it remained blocked, the tension built up to a limit.

By the time the eastern portion of the crater subplate was finally subducted, the Mariana Trench was formed at the subduction region — and the Pacific Plate resumed its path in accordance with the underlying magma.

This occurrence is evident and datable by the change of direction shown by the abrupt turn of the Hawaii-Emperor seamount chain, as previously mentioned.

This study cites earthquakes and volcanic activities in Peru and Chile, as well as earthquakes in Bolivia, as related to the impact of Wegener.

However, it is well known that these events are caused by the subduction of the Nazca Plate advancing below the South American Plate — and not by the Pacific Plate.

On the contrary, the Pacific Plate drifts away from America faster than the advance of the South American Plate.

The Nazca Plate is located much further up north than the proposed Antarctic hotspot for the Wegener Crater — in fact, retracing the two main seamount chains from the crater, we arrive at hotspots located on the Nazca Plate, as the example below.

Including the areas of orogenesis in the Andean region of South America, their shape is strangely circular — and it is remarkable that the area of ​​this circle is roughly 5,000 km in diameter, approximately equivalente to the diameter proposed to Wegener Crater.

To be fully understood, the disintegration process that resulted in these fractions dispersed across the Pacific and Antarctic oceans will need to be studied with the help of visual aids capable of simulating the movement of all parts involved, including neighbouring tectonic plates, in order to validate the estimated dates for the events.

1) Faunal evidence from Galápagos Islands?

Could the famous Galapagos tortoises be survivors of the same period when tuataras colonized New Zealand?

After all, the first turtles evolved during the Triassic, and species like Proganochellys already had all the characteristics of a typical turtle.

Another primitive reptile inhabiting the islands is the marine iguana, but because it is an aquatic animal, it is more difficult to relate its arrival to the islands as a result of colonization in the Triassic period — and there are many current strains present in South and Central America.

But the case of the islands themselves is different:

The current theory says that the Galápagos Islands are relatively recent, formed between 8 million to a maximum of 90 million years ago.

However, if the Nazca Plate was actually formed by the impact of Wegener, it is extremely old, exactly 251 ± 2.6 million years old.

In addition, the Galápagos Islands are located exactly on the outer secondary ring, perfectly aligned with two other hotspots — Easter Island and Juan Fernandez Islands.

And there is a curious and surprising coincidence between the hotspots on the Nazca Plate and some of the largest and most active volcanoes in the Philippine Plate/Mariana Plate fraction of Wegener Crater:

Image: Google Earth and NAZCA PLATE on Wikipedia with diameter of 4,600 km overlapping circles

There is a perfect match between the largest volcano in Japan (Mount Aso), the largest volcano in the Philippines (Mayon volcano), the most active volcano in the Philippines (Taal volcano) and the most active volcano in Indonesia (Lokon-Empung).

90 million years old is the age attributed to the volcanic arc of the Caribbean which, according to another study by the author, is related to the Jurassic Extinction and the Central Atlantic Magmatic Province (CAMP) 201.3 million years ago.

Could there have been any other significant geological event capable of reactivating volcanic arcs about 90 million years ago in that region? 

This would have masked up the actual age of the crater indicated by the Caribbean volcanic arc — after all, the totality of the studied volcanic arcs are related to impact craters and extinction events, according to other studies by the author. (See the detailed explanation about reactivation of volcanic arcs in the Appendix at the last post.)

Volcanoes responsible for major eruptions such as Tambora and Krakatau are located a little further south, but we cannot rule out a relationship between them — their volcanic activity may be related to the pressure generated by the collision of the Wegener Crater subplate driven by the Pacific Plate.

So, could the Galapagos Islands be remnants of the outer secondary ring of the Wegener Crater?

Despite being a seductive theory, it is not possible to say that based only on the peculiar native fauna.

There is genetic evidence that the Galápagos tortoises split up from a South American branch just 8 to 12 million years ago[1],  reinforcing the hypothesis of their arrival to the islands by drifting on vegetation rafts — marine iguanas could also have used the same method of transportation to reach such a long distance.

But the question about these islands being a part of the outer secondary ring surely deserves to be investigated.

2) The anomalous geological zone on the coast of Chile

The triangular-shaped volcanic region between the Easter Island and San Felix hotspots possibly corresponds to the period when the Wegener Crater/Pacific Plate faced the resistance imposed by the Philippine Sea Plate/Mariana Plate when it was stopped by the Eurasian Plate.

Image: Google Earth

This event took place in recent times, as can be deduced from the short distance between the Chilean hotspots and the anomalous region.

Taking into account the relative displacement, we arrive at a value close to the estimated date near 47 million years ago.

Parking the plate over the impact hotspots formed this triangular region over a few tens of millions of years through a process similar to what formed the Bangui Magnetic Anomaly in Africa (result of an impact event several hundred million years ago at Central Plateau of Brazil, subject of another study).

The beginning of the shear and subduction of the Wegener Crater under the Mariana Trench facilitated the displacement of the Pacific Plate, which offered less resistance to the advance of the American Plate.

This has been reflected in the higher velocity of magma flow at the Mid-Atlantic Ridge borders in recent times, as evidenced by the parallel magmatic yield rifts crosswise to the ridge.

With a length of approximately 1,400 to 1,700 km on either side of the ridge, at a current rate of 32 mm/year this region of rapid magma flow can be dated between 44 and 53 million years ago, an average of 48.5 million years.

This dating almost coincides with the age of 50 million years attributed to the emergence of the Mariana Trench, and with the estimated the age for the change of direction of the Hawaii-Emperor seamount chain, 47 million years.[2]

3) Nazca Plate Puzzle Interpretation

The theory proposed in this study explains the drift of the Nazca Plate northwards is as follows:

The world was fundamentally different 252 million years ago.

The Antarctic continent comprised only the East Antarctica — West Antarctica would arise only with the Wegener impact.

East Antarctica was located south to Africa, but east to South America.

It only advanced to its current position after the impact, probably driven by the resurgence of the mantle.

Nazca Plate was displaced from its position at the South Pole, and pushed westward and up north.

The resistance offered by the Pacific Plate left no alternative for Nazca, which was forced to drift up north and east, pushed by two irresistible forces.

Continued on the next page

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[1] Origin and evolutionary relationships of giant Galápagos tortoises, Adalgisa Caccone, James P. Gibbs, Valerio Ketmaier, Elizabeth Suatoni, and Jeffrey R. Powell, PNAS November 9, 1999 96 (23) 13223-13228; https://doi.org/10.1073/pnas.96.23.13223, Communicated by John C. Avise, University of Georgia, Athens, Georgia (received for review May 28, 1999)

[2] The mysterious bend in the Hawaiian-Emperor chain, Helmholtz Association of German Research Centers

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