Super Smash Continent predicted

Connecticut could border the Andes Mountain Range instead of the Long Island Sound in millions of years, according to a new theory proposed by Yale scientists.

Researchers from Yale’s Department of Geology and Geophysics have developed a new supercontinent formation theory, which predicts that the continents will next come together in a giant landmass called Amasia, will form over the North Pole in 50 to 200 million years. The model, which is based on analyses of ancient rocks, challenges previous predictions on the location of the next supercontinent. Lead author Ross Mitchell GRD ’12 said the theory, published in the journal Nature on Feb. 8, could lead scientists to a better understanding of Earth’s history and modern-day composition.

“This is the most exciting work in Precambrian geology in recent years,” said Paul Hoffman, professor of geology at Harvard. “Contrary to the previous models that were purely geometrical, the new model actually makes sense geodynamically. It considers the forces that are acting on the [tectonic] plates and moving [the continents].” Hoffman was not involved with this study.

The Yale geologists analyzed the magnetism of ancient rocks and the relative positions between three previous supercontinents, including the last supercontinent, Pangaea, which formed over 300 million years ago and began to break apart 200 million years ago. Mitchell explained that when lava cooled and sedimentary layers solidified to form rocks millions of years ago, the metal within the rocks aligned with the Earth’s magnetic pole at unique latitudes. Analyzing this paleomagnetic data enabled the research team to map the movement of the continents relative to the magnetic north pole throughout time.

“We found that once a supercontinent formed, it tended to swivel around its own center.” said David Evans ’92, senior author and professor of geology and geophysics at Yale. “If we extrapolate that pattern, we can predict the location of the next supercontinent.”

From outer space, the entire supercontinent land mass would oscillate clockwise and then back counterclockwise, an effect called “true polar wander,” Mitchell said.

Based on true polar wander and the paleomagnetic data analysis, the Yale geologists proposed an “orthoversion” model in which the next supercontinent will be located 90 degrees away from Pangaea, which was centered near modern-day Africa. By this model, Amasia will form when the Americas meet Europe, Asia and Australia at the North Pole, closing the Arctic Ocean. Evans said Antarctica may remain separated from Amasia.

The previously proposed “introversion” and “extroversion” models predict the formation of the next supercontinent along the equator either 0 degrees or 180 degrees away from Pangaea, respectively.

Mitchell explained that, in addition to making a prediction for millions of years from now, the new model would have practical applications. It could help energy firms such as Shell Oil Company find new oil reserves by analyzing how the continents aligned when the mineral deposits formed millions of years ago, he said. The research could also help scientists study how species dispersed when Pangaea broke up, and could lead to better understandings of the earth and its changing surface geography.

“The history of the supercontinents is crucial to understanding the history of life, and the history of mineral and ore deposits,” Mitchell said.

Hoffman coined the name Amasia in 1992, as a joke about the future proximity of America and Asia, he said.

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