The animation begins with the modern world and then goes back to 240 million years ago (Triassic). The animation then reverses direction, allowing us to see how Pangea split to form modern continents and ocean basins. When the animation returns to the present day, it continues for another 250 million years until the formation of the next Pangea, /"Pangea Proxima/".
This question comes up often. /"Why don't you show East Africa separating from the rest of Africa?/".
Here's why:
– Often, oceans open around a three-arm rift system called a "triple junction." Only two arms of a triple junction open to form ocean basins. . In the case of East Africa, the Red Sea and the Gulf of Aden are the two successful divisions. The East African rift system, beginning at the Afar Triangle, Ethiopia, is an aulacogen or "failing arm" of a triple junction. The East African rift system is a failed rift, just like the Benue Trench in the South Atlantic or the Labrador Sea in the South Atlantic. North Atlantic.
– Let's step back and ask the question: "What caused the Red Sea, Gulf of Aden and East Africa to fracture in the first place?" Although the Afar hotspot certainly contributed to weakening the lithosphere, the driving force that caused rifting was the subduction (under Eurasia, i.e. Iran) of attached oceanic crust on the northern margin of Arabia. (There was an ocean, an ocean between Arabia and Iran.) This subducting slab “pulled” Arabia northward, away from Africa. This subduction zone was completely destroyed by the collision of Arabia and Eurasia (Zagros Mountains). Therefore, there are no more “plate tectonic forces” acting on the African rifts and they will not continue to open.
– Additionally, if we look at the plate tectonic neighborhood of East Africa, we see that the dominant plate motion in the western Indian Ocean is NS, rather than EW. In fact, a new subduction zone has just begun in the central Indian Ocean (a zone of diffuse 5-10 S earthquakes) that will continue to pull Australia and Antarctica northward, towards Asia. In other words, East Africa has no possibility of expanding eastward. The east coast of Madagascar will instead become a strike-slip margin allowing continued northward movement of the Australian-Antarctic plate.
I hope this explanation is helpful. Of course this is all scientific speculation, we'll have to wait and see what happens, but this is my projection based on my understanding of the forces that drive plate movements and the history of past movements plates. Remember: “The past reveals patterns; Models inform the process; The process makes it possible to predict.
Notice how the green (land), brown (mountains), dark blue (deep sea), and light blue (shallow seas on continents) areas change over time. These changes are the result of mountain building, erosion, and the rise and fall of sea levels over time. The white spots near the pole are the expanding and contracting polar ice caps.
The first part of the animation is a global view. The second part of the animation is a close-up view. This animation contains original music by CR Scotese, as well as an "easter egg/" at the end.
This animation can be freely used in museum exhibitions, on television and on the Internet. A high-resolution version of this animation is available upon request ([email protected]).
Credit: Scotese, CR, 2004. Plate tectonics and paleogeography (animation), PALEOMAP project, University of Texas at Arlington, Arlington, Texas (12:24).
CR Scotese publications can be downloaded free of charge at https://www.researchgate.net/profile/Christopher_Scotese3 or
https://uta.academia.edu/ChristopherScotese.
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