,

APPENDIX I
SIBERIA & THE PERMIAN EXTINCTION

   

Chapter nine of this book outlines some of the basic facts and ideas that undergird the linking of the creation of the Siberian continent with the Permian extinction that occurred approximately 250 MYA.

These basics include a 300 mile-in-diameter crater in Eastern Antarctica, the existence of the Siberian traps, the blob with a tail shape of the Siberian continent and the flood basalt lava in southern Alaska 235 MYA leading out to the Aleutian island chain (the follow-on hotspot).

The purpose of Appendix I is to provide more detail about the formation and movement of the Siberian continent.

The impact crater location in Eastern Antarctica and the Wrangellia flood basalts (231 - 225 MYA, which would have been the first separate activity of the Siberian hotspot after falling behind the moving Siberian continent) in Alaska and Canada give us a reasonably good picture of where the Siberian continent started out. We can see from the final position of Siberia that the Siberian traps were on the east side of the continent when it was first formed.

The blob part of the continent had a significant south and western momentum that caused it to turn to the west and then to the south.

This movement is corroborated in an unusual way by an article in the Journal of the Geological Society in 2007. Entitled "Siberian trap magmatism on the New Siberian islands" by Alexander B. Kuzmichev and Victoria L. Pease, this article presents evidence that islands near the Siberian traps are not geologically different from Siberia, itself.

In the course of the investigation, the authors found that the arctic basin in the Alaska/Siberia area showed a rotated terrane. Furthermore, the terrane rotated around a pivot point in extreme northeast Alaska. The rotation in the Siberian area was to the south. 81 pg 960

The authors were not looking to corroborate a model such as the one that I present. Nevertheless, their terrane conclusions do actually match the scenario that my model proposes. With the flood basalt lava located on the east side of the newly uplifted continent, we would expect movement to the west (see Appendix VII, Sidespin). Later, due to the Coriolis effect, we would expect movement to the south. A pivot point near northeast Alaska is right about where we would expect to find it.

THE ROCKY MOUNTAINS

The creation and movement of the Siberian continent had a significant impact on the western side of the North American continent.

Not only did it create the Rocky Mountains (as well as most of the western mountains in Canada and Alaska), but it also left behind a ridge on the Pacific tectonic plate. This ridge was formed by the westward turn of the Siberian tail of the new continent (just as the Indian Continent pushed up part of Java and Sumatra and the Thailand and Malay peninsulas).

This westward turn of the tail pushed up enough material that the Pacific plate could not subduct beneath the North American plate, once the tail of the Siberian plate had moved to the north. Therefore, at this juncture of the Pacific plate and the North American plate, we see the San Andreas fault and a strike slip system, rather than a subduction system.

The creation of the Rocky Mountains, as well as the western Canadian mountains and the mountains in Alaska happened over a period of millions of years and involved several different aspects of the movement and breakup of the Siberian continent.

The Siberian continent was originally a very large continent. It was so big that it ended up breaking into several distinct pieces as it pivoted, turned and moved to the west and then to the south. The resulting plates from the creation of the Siberian continent are:

1. The western part of the North American plate (which includes Alaska and the eastern part of Siberia).

2. The eastern part of the Eurasian plate (which includes the rest of Siberia).

3. The middle tail piece pulled north and west along the Canadian Rockies.

4. The end of the Siberian tail broke off and was trapped between the San Andreas Fault and the high plains of the U.S.

TOO BIG TO BE STABLE

The original Siberian continent that was uplifted was so large that it was intrinsically unstable as it tried to move in one piece. If this huge continent had been moving on a truly flat surface, then it might have held together. However, it was moving on a curved surface, where the Coriolis effect gives a different direction of movement to each segment of this large object. Besides that, the underlying magma had different directional pressure along the length of the continent.

The magma that was located under each part of this huge, upraised continent was being pushed in different directions, due to the rotational nature of the energy at that point under the earth. In the case of a smaller, stubby continent (i.e. India), the rotational energy of the blob would take over and move the entire continent in that direction. In the case of a much larger continent, the different energies will cause the continent to split apart into multiple tectonic plates.

The far northern part of the Siberian blob contained an underlayment of magma with energy pushing in a southwestern direction. The southern part of the blob was underlain by magma pushing in a western direction.

It is also possible that the leading edge of the blob was initially located beyond the North Pole, accounting for its slight southward movement. This would mean that Old Australia was farther south, but that is certainly possible.

The result of these competing directional pressures was the eventual breakup of Siberia into either three or four plates:

1. UPPER BLOB - This part moved west and eventually south and became permanently affixed to Eurasia, as it crashed into the Ural Mountains and China.

2. LOWER BLOB - This part moved west but was also pushed north by the tail. The western edge of the Eastern North American Continent eventually ran into this section and raised up the Canadian Rockies as it was subducted. This combined mass continued moving west. Eventually, the western pull of the Upper Blob caused the far northern part of the North American to stretch apart (a quick glance at a map of northern Canada and Greenland will show how this area is stretched out like a fan). Finally, the southern movement of the Upper Blob was too much for the structural integrity of this part of the Siberian continent … the Upper Blob ended up permanently affixed to Asia, while the Lower Blob remained part of the stretched-out North American plate.


3. MAIN TAIL - Meanwhile, the main part of the tail of the blob was moving in a northern direction with at least a bit of a western twist. This piece experienced subducted the Eastern North American Plate in the Southern Canadian Rockies.

4. TAIL END - The tail end of the Siberian Continent followed the blob north and west. The tail subducted the western side of the Eastern North American Continent later on in Canada, forming the Canadian Rockies. Part of the blob and the tail pushed up earth on the Pacific Plate as the Siberian Continent made its arcing movement to the north and west. This pushed up earth prevented the Pacific Plate from subducting and consists of the land to the west of the San Andreas Fault, as well as Baja California. The lower part of the tail broke off as it was trapped between the San Andreas pushed up land and the western edge of Eastern North America, becoming the high plains and the American Rockies.

THE ROCKIES - A COMPLEX SYSTEM

One point in favor of examining the Rocky Mountains in North America is the fact that they have been studied a lot. And yet, the formation of the mountains in the western U.S. is so complex that not all answers are known. Answers to these questions are explored in detail in Appendix IV.

THE FOLLOW-ON HOTSPOT

The follow-on hotspot for the Siberian continent moved almost directly west from its original position at Wrangellia in Alaska, forming the Aleutian Islands.

However, because the North American plate did not move in a consistent manner during the 230 million years since the hotspot separated from the Siberian basalt flows, the Aleutians formed an arc, rather than a straight line. The reasons for this changing movement and the shape of the arc are detailed in the next three paragraphs.

The initial result of the collision of the Siberian continent and the western side of the North American continent was a gradual movement of the Siberian part of the North American continent (Alaska) to the north, as the blob rotated, pulling up the lower part of the blob and bringing the tail along, until the tail broke off.

Because the Alaska area was moving north, the west-moving hotspot appeared to be moving south.

This all changed 65 MYA, when the Chicxulub impact pulled the North American continent to the south, causing the west-moving hotspot to appear to move north. 41 pg 960, 42, 43 pg 14