WATCH EARTH'S TECTONIC PLATE MOVEMENT OF LAST BILLION YEARS IN 40 SECONDS
The earth once told a different story than it does today. Several supercontinents have broken up and come back together over time. The land mass that became Antarctica once sat along the Equator.
The Earth formed 4.4 billion years ago, where it then cooled down enough to form a solid crust. Then, individual plates formed roughly 1.2 billion years after. The centre of the Earth consists of a 1,800 mile thick, semi-solid mantle that encircles a super-hot core. The top layer is, however, only 21 miles thick, and is known as the crust which is fragmented into tectonic plates that fit together.
More than 3 billion years of planetary evolution resulted in the seven continents and five oceans as we know them today.
For the first time, a group of geologists have offered up an easily digestible view at 1 billion years of plate tectonic motion. However, charting the precise movements of those plates over billions of years is challenging. There are existing models which span only a few million years, or only focus on continental or oceanic changes, but not both.
The team of geoscientists from the University of Sydney, spent four years working on reconstructing how landmasses and oceans changed over the last billion years. They animated those changes as part of their recent study into the short video.
The animation shows green continents which are lumbering across the white oceans. The 'Ma' at the top of the video represents 1 million; in this case, 1,000 Ma is 1 billion years ago.
In order to identify the different types of boundaries between tectonic plates, each boundary were assigned a specific colour. Blue-purple lines represent divergent boundaries, where plates split apart; red triangles indicate convergent boundaries, where plates move together; and grey-green curves show transform boundaries, where plates slide sideways past each other.
Sabin Zahirovic, a University of Sydney geologist who co-authored the new study, stated in a press release that; "These plates move at the speed that fingernails grow, but when a billion years is condensed into 40 seconds, a mesmerizing dance is revealed."
By analyzing what's known as paleomagnetic data, geologists were able to piece together a picture of which plates were where hundreds of millions of years ago.
After lava at the junction of two tectonic plates cools down, some of the resulting rock will contain magnetic minerals which will align with the directions of Earth's magnetic poles at the time the rock solidified. Even after the plates containing those rocks have moved, researchers can study that magnetic alignment to parse where on the global map those natural magnets existed in the past.
By using paleomagnetics and current tectonic plate data, the study authors created the most thorough map of each plate's journey from 1 billion years ago until the present.
Dietmar Müller, a co-author of the study, stated that; "Simply put, this complete model will help explain how our home, planet Earth, became habitable for complex creatures."