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In 2021, geologists have animated a video showing how the Earth works tectonic plates moved in the last billion years.
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The plates move together and apart at the rate of fingernail growth, and the video accelerates the process to under a minute.
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The animation shows the formations that formed off our current seven continents and five oceans.
The landmass that became Antarctica was once on the equator. Over the course of Earth's history, several supercontinents have broken apart and come back together.
Our current seven continents and five oceans are the result of more than three billion years of planetary evolution, with tectonic plates criss-crossing above them semi-rigid coat layerthe asthenosphere.
However, it is a challenge to record the precise movements of these plates over time. Existing models often span only a few million years or only focus on continental or oceanic changes, not both.
But in 2021, a group of geologists offered an easy-to-understand glimpse into 1 billion years of plate tectonic motion.
Geoscientists at the University of Sydney spent four years reconstructing how landmasses and oceans have changed over the past billions of years. As part of a study from 2021they animated these changes in the short video below.
The animation shows green continents slugging across oceans shown in white. The Ma at the top of the video stands for mega year or 1 million years, so 1,000 Ma is 1 billion years ago.
The different color lines represent different types of boundaries between tectonic plates: Blue-purple lines represent divergent borders, where plates break apart; Red triangles indicate convergent boundaries where plates are moving together. and gray-green curves show transformation boundaries where plates slide laterally past each other.
“These plates move at the rate that fingernails grow, but when you cram a billion years into 40 seconds, it creates a mesmerizing dance,” said Sabin Zahirovic, a University of Sydney geologist who co-authored the study in a press release.
Creating a better model of the Earth's plates
The oldest crust of the earth was formed 4.4 billion years agoIt cooled so much that it solidified about 100 million years after the planet formed.
subductionwhen the edge of one plate slips under another has led to the formation and disintegration of at least one plate five supercontinents, including Kenorland, Rodinia and Pangea. The video shows Pangea slowly breaking up into today's continents about 175 million years ago.
Today you can think of the planet as a chocolate truffle – a viscous center embedded in a hardened shell. The center consists of a 1,800 miles thick semi-solid coat surrounding a super hot core. The top layer – in between 5 and 50 miles thick – is the crust fragmented into mating tectonic plates.
These plates float on Earth's mantle and move as hotter, less dense material from deep within the Earth rises toward the crust and colder, denser material sinks toward the core.
By analyzing what are known as plates, geologists can get a picture of where the plates were hundreds of millions of years ago paleomagnetic data. When lava cools at the junction of two tectonic plates, some of the resulting rock remains contained Iron-rich minerals that align with the directions of the earth's magnetic poles at the time of solidification of the rock.
Even after the plates containing these rocks have moved, researchers can find out where on the world map these natural magnets existed in the past.
Using both paleomagnetic and recent tectonic plate data, the study's authors were able to create a comprehensive map of each plate's journey from a billion years ago to the present.
“Put simply, this complete model will help explain how our home, planet Earth, became habitable for complex creatures,” said Dietmar Müller, co-author of the study, in the press release.
The jigsaw puzzle of Earth's continents, of course, hasn't stopped shifting. The Pacific Ocean, for example, is shrinking every year. The Atlantic is now widening – Displace America from Africa and Europe.
This post has been updated. It was originally released on February 14, 2021.
Check out the original article Business Insider
