What Year Will the Continents Be Together Again
Will there ever be another Pangaea?
Just before the dawn of the dinosaurs — roughly 251 million years agone — World's continents abutted one some other, merging to course the supercontinent Pangaea. That land mass, which straddled the equator like an aboriginal Pac-Man, somewhen split into Gondwana in the south and Laurasia in the north.
From in that location, Gondwana and Laurasia separated into the vii continents that we know today. But the constant motion of Earth's tectonic plates raises a question: Volition there always be another supercontinent like Pangaea?
The respond is yes. Pangaea wasn't the kickoff supercontinent to form during Earth'southward 4.5-billion-year geologic history, and it won't be the last.
Related: What Is Plate Tectonics?
"That'south the one office of the contend that there isn't much debate over," Ross Mitchell, a geologist at Curtin Academy in Perth, Australia, told Alive Scientific discipline. "Merely what 'the next Pangaea' volition look similar … that's where opinions diverge."
Geologists concord that there is a well-established, fairly regular cycle of supercontinent formation. It's happened 3 times in the past. The first one was Nuna (likewise called Columbia), which existed from about 1.viii billion to one.3 billion years ago. Next came Rodinia, which dominated the planet betwixt 1.2 billion and 750 one thousand thousand years ago. So, in that location'due south no reason to think that another supercontinent won't form in the future, Mitchell said.
The convergence and spreading of continents are tied to movements of tectonic plates. The Globe's crust is divided into ix major plates that glide over the mantle, the liquid layer that sits betwixt the core and the semi-solid crust. In a process called convection, hotter material rises from nigh the Earth'southward core toward the surface, while colder mantle rock sinks. The ascension and falling of drapery material either spreads plates autonomously, or forces them together by pushing 1 under another.
Scientists can rail tectonic plate movements using GPS instruments. Simply in order to piece together what these plates were up to millions of years ago, paleogeologists have to turn to natural magnets in the World's crust. As hot lava cools at the junction where ii plates are colliding, some rocks in the lava containing magnetic minerals, such as magnetite, align with Earth'southward electric current magnetic fields. As the and so-cooled stone moves via plate tectonics, scientists can employ that alignment to summate where, in terms of latitude, those magnets were located in the by.
According to Mitchell, a new supercontinent forms every 600 million years or and then, merely that cycle might exist speeding upwards. This suggests that the adjacent Pangaea, dubbed Amasia (or Pangaea Proxima) would class sooner than nosotros look. Mitchell thinks the cycle is speeding upwardly because the World's internal heat — hoarded in the planet'due south cadre since the time of its formation — is dissipating, meaning that convection is happening faster.
"Given that the heyday of Pangaea was probably 300 meg years ago, Amasia's would be 300 1000000 years from now," Mitchell said. "But it could form equally soon as 200 one thousand thousand years from now."
Even so, predicting the birth year of Amasia isn't so unproblematic.
"The difficult matter about predicting the Pangaea of the futurity is that you can't accept present-day plate motions and hit fast-forward," Mitchell said. Plate motions can change unexpectedly, with imperfections in the seafloor causing plates to veer from their trajectories.
Soon, California and east asia are converging toward Hawaii, while North America is moving farther and farther away from Europe, Matthias Light-green, an oceanographer at Bangor Academy in the United Kingdom, told Live Science. Meanwhile, Australia is drifting north on a collision course with Korea and Nippon, and Africa is rotating northward toward Europe. These movements, of course, are happening at the rate of centimeters per year, about the speed that your hair and nails abound.
Mitchell and Green said there are a handful of prevailing ideas near what the side by side geologic game of "Tetris" might look similar. The Atlantic Ocean could close upwardly, with northern Canada crashing into the Iberian Peninsula and Due south America colliding with southern Africa roughly where Pangaea used to be. Or the Pacific Ocean could disappear, subsumed by Asia and Northward America. Mitchell had 1 additional, out-of-the-box hypothesis: that North America and Asia might move n to converge over the Chill, quashing the Arctic Ocean.
And then, how might the formation of the side by side Pangaea affect life on Earth (assuming in that location's notwithstanding flora and animal 300 million years from now)?
Information technology will definitely change existing conditions and climate patterns and affect existing biodiversity, Green said. "The largest mass extinction issue to date happened during Pangaea," Green said. "Was that considering nosotros were on a supercontinent? Or coincidence?"
He's referring to the Permian-Triassic extinction, dubbed "the Keen Dying," when ninety% of the world's species died out 250 meg years ago. Just after Pangaea formed, two major volcanic eruptions spewed big amounts of methane and carbon dioxide into the atmosphere, which may accept contributed to the mass die-off. Merely scientists aren't in agreement most whether plate tectonics and the convection processes that formed Pangaea are linked to these disquisitional volcanic events.
It'due south unclear what's in store for life on Earth when the next supercontinent forms. But, thank you to scientists like Mitchell and Green, we may at to the lowest degree know what our atlases should look similar a few hundred one thousand thousand years from now.
Original commodity on Live Science.
Source: https://www.livescience.com/63753-will-there-be-another-pangea.html
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