About million years ago, Pangaea was still stitched together, yet to be ripped apart by the geological forces that shaped the continents as we know them today. For many years, geologists have pondered how all the pieces originally fit together, why they came apart the way they did and how they ended up spread across the globe.
Read more: Plate tectonics: new findings fill out the year-old theory that explains Earth's landmasses. As an assistant professor in structural geology , I research plate tectonics — specifically how and why continents break up — and the related igneous rocks, natural resources and hazards. We know that Nova Scotia and Morocco were once attached because their coastal areas — or margins — match up perfectly.
We can also trace their path from the structure of the ocean floor now separating them. Today, we are much closer to understanding the shifting of the continents, including the movement of land masses, but there is still much to learn. The science of exactly why they ended up 5, km away from each other — and how other parts of the continental jigsaw puzzle pulled apart the way they did — has been extensively researched and debated.
One camp believes the continents were dragged apart by the movement of tectonic plates driven by forces elsewhere. The universe grew and cooled and eventually stars and galaxies formed. Source: Futurism. It was formed by collisions of particles in a large cloud of material. Slowly gravity gathered together all these particles of dust and gas and formed larger clumps.
These clumps continued to collide and gradually grew bigger and bigger eventually forming the Earth. The earth at this time was very different to how we know it today. Earth's Tectonic History In the last section we looked at plate tectonics and the movement of the large plates that make up the Earth's crust. Here we will look at how plate tectonics has changed the face of the earth over the last few billion years and how it is continuing to change.
The idea of continental drift was the forerunner of the theory of plate tectonics. Plate tectonics is thought of as the unifying theory as all of geology can be explained using it. By looking at the globe, we can see that the east coast of South America seems to fit perfectly, almost like a puzzle, into the west coast of Africa.
We can also see that North America can be rotated slightly and made to fit comfortably next to Europe, and Asia.
Take a look at a map and see if you can see this. What are the different types of rocks? What is a fossil and what are they used for? What are hydrothermal vents, and why do we find them along mid-ocean ridges?
Seismology What is a seismic wave? What is the difference between body waves and surface waves, and between P-waves and S-waves? Why can't S-waves travel through liquids? How far can seismic waves reach? Why do P-waves travel faster than S-waves? Why is the interior of the Earth hot?
What is the magnetic field of the Earth? Earthquakes and Faults Why do tectonic plates move? Brief history of the plate tectonics theory Before colliding with Asia, where was India? What is an earthquake? What is the highest magnitude an earthquake can reach? The explanation for Pangaea's formation ushered in the modern theory of plate tectonics , which posits that the Earth's outer shell is broken up into several plates that slide over Earth's rocky shell, the mantle.
Over the course of the planet's 3. This breakup and formation of supercontinents has dramatically altered the planet's history. This is the major backbeat of the planet," said Brendan Murphy, a geology professor at the St.
More than a century ago, the scientist Alfred Wegener proposed the notion of an ancient supercontinent, which he named Pangaea sometimes spelled Pangea , after putting together several lines of evidence. The first and most obvious was that the "continents fit together like a tongue and groove," something that was quite noticeable on any accurate map, Murphy said.
Another telltale hint that Earth's continents were all one land mass comes from the geologic record. Coal deposits found in Pennsylvania have a similar composition to those spanning across Poland, Great Britain and Germany from the same time period.
That indicates that North America and Europe must have once been a single landmass. And the orientation of magnetic minerals in geologic sediments reveals how Earth's magnetic poles migrated over geologic time, Murphy said. In the fossil record, identical plants, such as the extinct seed fern Glossopteris , are found on now widely disparate continents. And mountain chains that now lie on different continents, such as the Appalachians in the United States and the Atlas Mountains in Morocco, were all part of the Central Pangaea Mountains, formed through the collision of the supercontinents Gondwana and Laurussia.
Pangaea formed through a gradual process spanning a few hundred million years.
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