New model of plate tectonics shows how Earth was organized as a supercontinent 2.8 million years ago

New model of plate tectonics shows how Earth was organized as a supercontinent 2.8 million years ago: Scientists hope it will help predict natural hazards like earthquakes and volcanoes

  • A new model of Earth’s tectonic plates aims to help us better understand earthquakes and volcanoes
  • The model organizes continents like the first supercontinent, Vaalbara
  • Vaalbara broke apart about 2.8 million years ago
  • Using this design allowed scientists to include more microplates
  • This allowed them to better explain ‘the spatial distribution of 90% of earthquakes and 80% of volcanoes over the last 2 million years.

Scientists have produced a new map of Earth’s tectonic plates that shows the continents organized like the first supercontinent, Vaalbara, which broke apart about 2.8 million years ago.

The team, led by the University of Adelaide, believes the updated model will help provide a better understanding of natural hazards such as earthquakes and volcanoes.

Plate tectonics are the gradual drift of continents across the Earth’s surface that causes earthquakes and volcanoes to erupt.

By reversing millions of years back, scientists can include new microplates such as the Macquarie microplate, which is south of Tasmania, and the Capricorn microplate, which separates the Indian and Australian plates.

This allowed them to better explain “the spatial distribution of 90% of earthquakes and 80% of volcanoes over the past two million years, while existing models capture only 65% ​​of earthquakes,” said Dr. from Adelaide who led the team, in a statement.

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Scientists have produced a new map of Earth’s tectonic plates that shows the continents organized like the first supercontinent, Vaalbara, which broke apart about 2.8 million years ago.

To obtain these statistics, Hasterok and his team also added more precise information about the boundaries of the deformation zones: previous models showed discrete areas rather than wide zones.

“The biggest changes in the plate model occurred in western North America, which generally has the boundary with the Pacific Plate drawn like the San Andreas and Queen Charlotte faults,” Hasterok said.

‘But the newly delineated boundary is much wider, approximately 1500 km [932 miles]than the previously drawn narrow zone.

“The other big change is in Central Asia. The new model now includes all warp zones north of India as the plate makes its way into Eurasia.’

This allowed them to better explain

This allowed them to better explain “the spatial distribution of 90% of earthquakes and 80% of volcanoes over the past two million years, while existing models (pictured) only capture 65% of earthquakes.”

The last time the plate tectonics model was updated was in 2003.

‘The plate model can be used to improve geohazard risk models; the orogeny model helps to understand geodynamic systems and better models the evolution of the Earth and the province model can be used to improve mineral prospecting’, Hasterok said.

A separate study, published in 2019, supports the new model, as it found that plate tectonics began to form around 2.5 billion years ago — just before Vaalbara broke apart.

To assess when Earth’s plate tectonics began, geologist Robert Holder of Johns Hopkins University in Baltimore and his colleagues studied metamorphic rocks from 564 sites around the world that date back 3 billion years.

Metamorphic rocks are those that form when other types of rocks — those made from sediment, or those that cool from lava or magma — are altered by extreme temperatures or pressures.

By reversing millions of years back, scientists are able to include new microplates such as the Macquarie microplate that lies south of Tasmania and the Capricorn microplate that separates the Indian and Australian plates.

By reversing millions of years back, scientists are able to include new microplates such as the Macquarie microplate that lies south of Tasmania and the Capricorn microplate that separates the Indian and Australian plates.

By analyzing these rocks, the team was able to determine the depths and temperatures at which they formed, building a picture of the changing heat flux in different places on the Earth’s crust – and, in turn, the tectonic plates that control them.

The paper’s author and Curtin University geologist Tim Johnson said in a statement: “Some geologists consider that the Earth has had plate tectonics throughout its four and a half billion year existence.

‘While others consider that plate tectonics appeared abruptly about a billion years ago.

“Using a simple statistical analysis of the temperature, pressure and age of metamorphic rocks, we reveal that plate tectonics evolved gradually over the last 2.5 billion years as our planet slowly cooled.”

Earth is moving under our feet: tectonic plates move through the mantle and produce earthquakes as they rub against each other

Tectonic plates are made up of the Earth’s crust and the upper part of the mantle.

Below is the asthenosphere: the conveyor belt of hot, viscous rock over which tectonic plates move.

The Earth has fifteen tectonic plates (pictured) that together shaped the shape of the landscape we see around us today.

The Earth has fifteen tectonic plates (pictured) that together shaped the shape of the landscape we see around us today.

Earthquakes often occur at tectonic plate boundaries, where one plate dips below another, pushes another up, or where the edges of plates scrape against each other.

Earthquakes rarely occur in the middle of plates, but they can happen when old faults or rifts far below the surface reactivate.

These areas are relatively weak compared to the surrounding plate and can easily slip and cause an earthquake.

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