what is a hypothesis of continental drift

Continental Drift: The groundbreaking theory of moving continents

Continental drift theory introduced the idea of moving continents.

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Continental drift was a revolutionary theory explaining that continents shift position on Earth's surface. The theory was proposed by geophysicist and meteorologist Alfred Wegener in 1912, but was rejected by mainstream science at the time. Scientists confirmed some of Wegener's ideas decades later, which are now part of the widely accepted theory of plate tectonics .

Wegener's continental drift theory introduced the idea of moving continents to geoscience. He proposed that Earth must have once been a single supercontinent before breaking up to form several different continents. This explained how similar rock formations and plant and animal fossils could exist on separated continents. Modern science recognizes this ancient supercontinent called Pangaea did exist before breaking up about 200 million years ago, as Wegener theorized. 

Related: Massive supercontinent will form hundreds of millions of years from now  

Why did scientists reject Wegener's continental drift theory?

Geologists roundly denounced Wegener's continental drift theory after he published the details in a 1915 book called " The Origin of Continents and Oceans ." Part of the opposition was because Wegener didn't have a good model to explain how the continents moved, something scientists later explained under the umbrella of plate tectonics — the theory that Earth's crust is fractured into plates that move over a rocky inner layer called the mantle . 

"There's an irony that the key objection to continent drift was that there is no mechanism, and plate tectonics was accepted without a mechanism," to move the continents, Henry Frankel (1944–2019), an emeritus professor at the University of Missouri-Kansas City and author of the four volume " The Continental Drift Controversy " (Cambridge University Press, 2012) previously told Live Science.

Though most of Wegener's observations about fossils and rocks were correct, he was outlandishly wrong on a couple of key points. For instance, Wegener thought the continents might have plowed through the ocean crust like icebreakers smashing through ice. 

When Wegener proposed continental drift, many geologists were contractionists. They thought Earth's incredible mountains were created because our planet had been cooling and shrinking since its formation, Frankel said. And to account for the identical fossils discovered on continents such as South America and Africa, scientists invoked ancient land bridges, now vanished beneath the sea. 

Researchers argued over the land bridges right up until the plate tectonics theory was developed from the 1950s to the 1970s, Frankel said. For instance, as geophysicists began to realize that continental rocks were too light to sink down to the ocean floor, prominent paleontologists instead wrongly suggested that the similarities between fossils had been overestimated, Frankel said.

Plate tectonics is like a modern update to continental drift. In the 1960s, scientists discovered plate edges through magnetic surveys of the ocean floor and through the seismic listening networks built to monitor nuclear testing, according to Encyclopedia Britannica . Alternating patterns of magnetic anomalies on the ocean floor indicated seafloor spreading , where new plate material is born. Magnetic minerals aligned in ancient rocks on continents also showed that the continents have shifted relative to one another. 

Related: Plate tectonics are 3.6 billion years old, oldest minerals on Earth reveal  

What evidence is there for continental drift?

A map of the continents inspired Wegener's quest to explain Earth's geologic history. He was intrigued by the interlocking fit of Africa's and South America's shorelines. Wegener then assembled an impressive amount of continental drift evidence to show that Earth's continents were once connected in a single supercontinent.

Wegener knew that fossil plants and animals such as mesosaurs , a freshwater reptile found only in South America and Africa during the Permian period, could be found on many continents. He also matched up rock formations on either side of the Atlantic Ocean like puzzle pieces. For example, the Appalachian Mountains (United States) and Caledonian Mountains (Scotland) fit together, as do the Karoo strata in South Africa and Santa Catarina rocks in Brazil.

In fact, plates moving together created the highest mountains in the world, the Himalayans, and the mountains are still growing due to the plates pushing together, even now, according to National Geographic . Despite his incredible continental drift evidence, Wegener never lived to see his theory gain wider acceptance. He died in 1930 at age 50 just two days after his birthday while on a scientific expedition in Greenland , according to the University of Berkeley .

• Learn more about the history of continental drift and plate tectonics from the U.S. Geological Survey . 
• Learn more about Alfred Wegener from the NASA Earth Observatory . 
• Watch this short video on YouTube about plate tectonics and continental drift, from National Geographic . 

This article was updated on Dec. 14, 2021, by Live Science Staff Writer Patrick Pester. Additional reporting by Alina Bradford, Live Science contributor.  

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The Continental Drift Theory: Revolutionary and Significant

• Plate Tectonics
• Types Of Rocks
• Landforms and Geologic Features
• Weather & Climate

Opposition to Continental Drift Theory

Data supporting continental drift theory.

• Wegener's Search for Scientific Truth

Acceptance of Continental Drift Theory

• MLA, Harvard Graduate School of Design

Continental drift was a revolutionary scientific theory developed in the years 1908-1912 by Alfred Wegener (1880-1930), a German meteorologist, climatologist, and geophysicist, that put forth the hypothesis that the continents had all originally been a part of one enormous landmass or supercontinent about 240 million years ago before breaking apart and drifting to their current locations. Based on the work of previous scientists who had theorized about horizontal movement of the continents over the Earth's surface during different periods of geologic time, and based on his own observations drawing from different fields of science, Wegener postulated that about 200 million years ago, a supercontinent that he called Pangaea (which means "all lands" in Greek) began to break up. Over millions of years the pieces separated, first into two smaller supercontinents, Laurasia and Gondwanaland, during the Jurassic period and then by the end of the Cretaceous period into the continents we know today.

Wegener first presented his ideas in 1912 and then published them in 1915 in his controversial book, "The Origins of Continents and Oceans , " which was received with great skepticism and even hostility. He revised and published subsequent editions of his book in 1920,1922, and 1929. The book (Dover translation of the 1929 fourth German edition) is still available today on Amazon and elsewhere.

Wegener's theory, although not completely correct, and by his own admission, incomplete, sought to explain why similar species of animals and plants, fossil remains, and rock formations exist on disparate lands separated by great distances of sea. It was an important and influential step that ultimately led to the development of the theory of plate tectonics , which is how scientists understand the structure, history, and dynamics of the Earth’s crust.

There was much opposition to Wegener's theory for several reasons. For one, he was not an expert in the field of science in which he was making a hypothesis , and for another, his radical theory threatened conventional and accepted ideas of the time. Furthermore, because he was making observations that were multidisciplinary, there were more scientists to find fault with them.

There were also alternative theories to counter Wegener’s continental drift theory. A commonly held theory to explain the presence of fossils on disparate lands was that there was once a network of land bridges connecting the continents that had sunk into the sea as part of a general cooling and contraction of the earth. Wegener, however, refuted this theory maintaining that continents were made of a less dense rock than that of the deep-sea floor and so would have risen to the surface again once the force weighing them down had been lifted. Since this had not occurred, according to Wegener, the only logical alternative was that the continents themselves had been joined and had since drifted apart.

Another theory was that the fossils of temperate species found in the arctic regions were carried there by warm water currents. Scientists debunked these theories, but at the time they helped stall Wegener’s theory from gaining acceptance.

In addition, many of the geologists who were Wegener's contemporaries were contractionists. They believed that the Earth was in the process of cooling and shrinking, an idea they used to explain the formation of mountains, much like wrinkles on a prune. Wegener, though, pointed out that if this were true, mountains would be scattered evenly all over the Earth's surface rather than lined up in narrow bands, usually at the edge of a continent. He also offered a more plausible explanation for mountain ranges. He said they formed when the edge of a drifting continent crumpled and folded — as when India hit Asia and formed the Himalayas.

One of the biggest flaws of Wegener’s continental drift theory was that he did not have a viable explanation for how continental drift could have occurred. He proposed two different mechanisms, but each was weak and could be disproven. One was based on the centrifugal force caused by the rotation of the Earth, and the other was based on the tidal attraction of the sun and the moon.

Though much of what Wegener theorized was correct, the few things that were wrong were held against him and prevented him from seeing his theory accepted by the scientific community during his lifetime. However, what he got right paved the way for plate tectonics theory.

Fossil remains of similar organisms on widely disparate continents support the theories of continental drift and plate tectonics. Similar fossil remains, such as those of the Triassic land reptile Lystrosaurus and the fossil plant Glossopteris , exist in South America, Africa, India, Antarctica, and Australia, which were the continents comprising Gondwanaland, one of the supercontinents that broke off from Pangaea about 200 million years ago. Another fossil type, that of the ancient reptile Mesosaurus , is only found in southern Africa and South America.  Mesosaurus was a freshwater reptile only one meter long that could not have swum the Atlantic Ocean, indicating that there was once a contiguous landmass that provided a habitat for it of freshwater lakes and rivers.

Wegener found evidence of tropical plant fossils and coal deposits in the frigid arctic near the North Pole, as well as evidence of glaciation on the plains of Africa, suggesting a different configuration and placement of the continents than their present one.

Wegener observed that the continents and their rock strata fit together like pieces of a jigsaw puzzle, particularly the east coast of South America and the west coast of Africa, specifically the Karoo strata in South Africa and Santa Catarina rocks in Brazil. South America and Africa were not the only continents with similar geology , though. Wegener discovered that the Appalachian Mountains of the eastern United States, for instance, were geologically related to the Caledonian Mountains of Scotland. 

Wegener's Search for Scientific Truth

According to Wegener, scientists still did not appear to understand sufficiently that all earth sciences must contribute evidence toward unveiling the state of our planet in earlier times, and that the truth of the matter could only be reached by combing all this evidence. Only by combing the information furnished by all the earth sciences would there be hope to determine "truth," that is to say, to find the picture that sets out all the known facts in the best arrangement and that therefore has the highest degree of probability. Further, Wegener believed that scientists always need to be prepared for a possibility that a new discovery, no matter what science furnishes it, may modify the conclusions we draw.

Wegener had faith in his theory and persisted in using an interdisciplinary approach, drawing on the fields of geology, geography, biology, and paleontology, believing that to be the way to strengthen his case and to keep up the discussion about his theory. His book, "The Origins of Continents and Oceans , " also helped when it was published in multiple languages in 1922, which brought it worldwide and ongoing attention within the scientific community. When Wegener gained new information, he added to or revised his theory, and published new editions. He kept the discussion of the plausibility of the continental drift theory going until his untimely death in 1930 during a meteorologic expedition in Greenland.

The story of the continental drift theory and its contribution to scientific truth is a fascinating example of how the scientific process works and how scientific theory evolves. Science is based on hypothesis, theory, testing, and interpretation of data, but the interpretation can be skewed by the perspective of the scientist and his or her own field of specialty, or denial of facts altogether. As with any new theory or discovery, there are those who will resist it and those who embrace it. But through Wegener’s persistence, perseverance, and open-mindedness to the contributions of others, the theory of continental drift evolved into the widely accepted theory today of plate tectonics. With any great discovery it is through the sifting of data and facts contributed by multiple scientific sources, and ongoing refinements of the theory, that scientific truth emerges.

When Wegener died, discussion of continental drift died with him for a while. It was resurrected, however, with the study of seismology and further exploration of the ocean floors in the 1950s and 1960s that showed mid-ocean ridges, evidence in the seafloor of the Earth's changing magnetic field, and proof of seafloor spreading and mantle convection, leading to the theory of plate tectonics. This was the mechanism that was missing in Wegener's original theory of continental drift. By the late 1960s, plate tectonics was commonly accepted by geologists as accurate.

But the discovery of seafloor spreading disproved a part of Wegener's theory, because it wasn't just the continents that were moving through static oceans, as he had originally thought, but rather entire tectonic plates, consisting of the continents, ocean floors, and parts of the upper mantle. In a process similar to that of a conveyor belt, hot rock rises from the mid-ocean ridges and then sinks down as it cools and becomes denser, creating convection currents that cause movement of the tectonic plates.

The theories of continental drift and plate tectonics are the foundation of modern geology. Scientists believe that there were several supercontinents like Pangaea that formed and broke apart over the course of Earth's 4.5-billion year lifespan. Scientists also now recognize that Earth is constantly changing and that even today, the continents are still moving and changing. For example, the Himalayas, formed by the collision of the Indian plate and the Eurasian plate is still growing, because plate tectonics is still pushing the Indian plate into the Eurasian plate. We may even be heading toward the creation of another supercontinent in 75-80 million years due to the continued movement of tectonic plates.

But scientists are also realizing that plate tectonics does not work merely as a mechanical process but as a complex feedback system, with even things such as climate affecting the movement of the plates, creating yet another quiet revolution in the theory of plate tectonics variable in our understanding of our complex planet.

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Plate Tectonics

Theory of continental drift.

The continental drift hypothesis was developed in the early part of the 20th century, mostly by Alfred Wegener. Wegener said that continents move around on Earth’s surface and that they were once joined together as a single supercontinent. While Wegener was alive, scientists did not believe that the continents could move.Find a map of the continents and cut each one out. Better yet, use a map where the edges of the continents show the continental shelf. That’s the true size and shape of a continent and many can be pieced together like a puzzle. The easiest link is between the eastern Americas and western Africa and Europe, but the rest can fit together too.

Alfred Wegener proposed that the continents were once united into a single supercontinent named Pangaea, meaning all earth in ancient Greek. He suggested that Pangaea broke up long ago and that the continents then moved to their current positions. He called his hypothesis continental drift.

Evidence for Continental Drift

Besides the way the continents fit together, Wegener and his supporters collected a great deal of evidence for the continental drift hypothesis. For one, identical rocks of the same type and age are found on both sides of the Atlantic Ocean. Wegener said the rocks had formed side-by-side and that the land had since moved apart.Mountain ranges with the same rock types, structures, and ages are now on opposite sides of the Atlantic Ocean. The Appalachians of the eastern United States and Canada, for example, are just like mountain ranges in eastern Greenland, Ireland, Great Britain, and Norway. Wegener concluded that they formed as a single mountain range that was separated as the continents drifted.Ancient fossils of the same species of extinct plants and animals are found in rocks of the same age but are on continents that are now widely separated. Wegener proposed that the organisms had lived side by side, but that the lands had moved apart after they were dead and fossilized. He suggested that the organisms would not have been able to travel across the oceans. For example, the fossils of the seed fern Glossopteris were too heavy to be carried so far by wind. The reptile Mesosaurus could only swim in fresh water. was a swimming reptile but could only swim in fresh water. Cynognathus and Lystrosaurus were land reptiles and were unable to swim.Grooves and rock deposits left by ancient glaciers are found today on different continents very close to the equator. This would indicate that the glaciers either formed in the middle of the ocean and/or covered most of the Earth. Today glaciers only form on land and nearer the poles. Wegener thought that the glaciers were centered over the southern land mass close to the South Pole and the continents moved to their present positions later on.Coral reefs and coal-forming swamps are found in tropical and subtropical environments, but ancient coal seams and coral reefs are found in locations where it is much too cold today. Wegener suggested that these creatures were alive in warm climate zones and that the fossils and coal later had drifted to new locations on the continents.Although Wegener’s evidence was sound, most geologists at the time rejected his hypothesis of continental drift. Scientists argued that there was no way to explain how solid continents could plow through solid oceanic crust. Wegener’s idea was nearly forgotten until technological advances presented even more evidence that the continents moved and gave scientists the tools to develop a mechanism for Wegener’s drifting continents.

Magnetic Polarity on the Same Continent with Rocks of Different Ages

Magnetic polarity on different continents with rocks of the same age.

• Dynamic Earth: Introduction to Physical Geography. Authored by : R. Adam Dastrup. Located at : http://www.opengeography.org/physical-geography.html . Project : Open Geography Education. License : CC BY-SA: Attribution-ShareAlike
• Fossil Map. Authored by : Osvaldocangaspadilla. Provided by : USGS. Located at : https://commons.wikimedia.org/wiki/File:Snider-Pellegrini_Wegener_fossil_map.svg . License : Public Domain: No Known Copyright

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What is Continental Drift?

In 1912, Alfred Wegener published a theory to explain why the Earth looked like a huge jigsaw. He believed the continents were once joined, forming a supercontinent he called Pangaea. Over 180 million years ago, this supercontinent began to “break up” due to continental drift.

Continental drift

During the 20th Century, scientists developed the theory of Plate Tectonics. The theory suggests that the crust of the Earth is split up into seven large plates (see map below) and a few smaller ones, all of which can slowly move around on the Earth’s surface. They lie on the ductile mantle that allows them to move. There are several explanations for the movement of the Earth’s plates, and these are explored in the Why do plates move? page.

The Earth’s main tectonic plates

What is the evidence for continental drift?

Wegener’s evidence for continental drift was that:

• the same types of fossilised plants and animals are found in South America and Africa;
• the east coast of South America fits the west coast of Africa like a jigsaw puzzle;
• rock formations and mountain chains match in South America and Africa;
• similar mineral deposits and natural resources, such as coal, exist along the east coast of Africa and the west coast of South America.

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Continental Drift versus Plate Tectonics

A scientific idea that was initially ridiculed paved the way for the theory of plate tectonics, which explains how Earth’s continents move.

Earth Science, Geology, Geography, Physical Geography

Alfred Wegener in Greenland

Plate tectonics is the theory that Earth's land masses are in constant motion. The realization that Earth's land masses move was first proposed by Alfred Wegener, which he called continental drift. He is shown here in Greenland.

Photograph from Pictoral Press

We don’t perceive that the continents we live on are moving. After all, it’s not as if an airplane flight between Europe and Africa takes five hours one year but only three hours the next. But the continents actually are shifting, very slowly, relative to one another. In the early 20th century, a scientific theory called continental drift was proposed about this migration of the continents . That theory was initially ridiculed, but it paved the way for another theory called plate tectonics that scientists have now accepted to explain how Earth’s continents move. The story begins with Alfred Wegener (1880–1930), a German meteorologist and geophysicist who noticed something curious when he looked at a map of the world. Wegener observed that the continents of South America and Africa looked like they would fit together remarkably well—take away the Atlantic Ocean and these two massive landforms would lock neatly together. He also noted that similar fossils were found on continents separated by oceans, additional evidence that perhaps the landforms had once been joined. He hypothesized that all of the modern-day continents had previously been clumped together in a super continent he called Pangaea (from ancient Greek, meaning “all lands” or “all the Earth”). Over millions of years, Wegener suggested, the continents had drifted apart. He did not know what drove this movement, however. Wegener first presented his idea of continental drift in 1912, but it was widely ridiculed and soon, mostly, forgotten. Wegener never lived to see his theory accepted—he died at the age of 50 while on an expedition in Greenland. Only decades later, in the 1960s, did the idea of continental drift resurface. That’s when technologies adapted from warfare made it possible to more thoroughly study Earth. Those advances included seismometers used to monitor ground shaking caused by nuclear testing and magnetometers to detect submarines. With seismometers , researchers discovered that earthquakes tended to occur in specific places rather than equally all over Earth. And scientists studying the seafloor with magnetometers found evidence of surprising magnetic variations near undersea ridges: alternating stripes of rock recorded a flip-flopping of Earth’s magnetic field . Together, these observations were consistent with a new theory proposed by researchers who built on Wegener’s original idea of continental drift —the theory of plate tectonics . According to this theory , Earth’s crust is broken into roughly 20 sections called tectonic plates on which the continents ride. When these plates press together and then move suddenly, energy is released in the form of earthquakes. That is why earthquakes do not occur everywhere on Earth—they’re clustered around the boundaries of tectonic plates. Plate tectonics also explains the stripes of rock on the seafloor with alternating magnetic properties: As buoyant, molten rock rises up from deep within Earth, it emerges from the space between spreading tectonic plates and hardens, creating a ridge. Because some minerals within rocks record the orientation of Earth’s magnetic poles and this orientation flips every 100,000 years or so, rocks near ocean ridges exhibit alternating magnetic stripes. Plate tectonics explains why Earth’s continents are moving; the theory of continental drift did not provide an explanation. Therefore, the theory of plate tectonics is more complete. It has gained widespread acceptance among scientists. This shift from one theory to another is an example of the scientific process: As more observations are made and measurements are collected, scientists revise their theories to be more accurate and consistent with the natural world. By running computer simulations of how Earth’s tectonic plates are moving, researchers can estimate where the planet's continents will likely be in the future. Because tectonic plates move very slowly—only a few centimeters per year, on average—it takes a long time to observe changes. Scientists have found that the planet’s continents will likely again be joined together in about 250 million years. Researchers have dubbed this future continental configuration “ Pangaea Proxima.” One intriguing aspect of Pangaea Proxima is that it will likely contain a new mountain range with some of the world’s highest mountains. That is because as Africa continues to migrate north it will collide with Europe, a collision that will probably create a Himalaya-scale mountain range. However, Christopher Scotese, one of the scientists who developed these simulations , cautions that it is difficult to predict exactly how the continents will be arranged in millions of years. “We don’t really know the future, obviously,” Scotese told NASA. “All we can do is make predictions of how plate motions will continue, what new things might happen, and where it will all end up.”

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5.2: Wegener and the Continental Drift Hypothesis

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What is continental drift?

Wegener put together a tremendous amount of evidence that the continents had been joined. He advanced a great idea. But other scientists didn't accept it.

Wegener’s Continental Drift Hypothesis

Wegener put his idea and his evidence together in his book, The Origin of Continents and Oceans . The book was first published in 1915. He included evidence that the continents had been joined. New editions of the book containing additional evidence were published later.

In his book he said that around 300 million years ago, the continents had all been joined. They created a single landmass he called Pangaea, meaning “all earth” in ancient Greek. The super-continent later broke apart. Since then the continents have been moving into their current positions. He called his hypothesis continental drift .

The Problem With The Hypothesis

Wegener had a lot of evidence to support his hypothesis. But he had a problem. The problem was that he could not explain how the continents could move through the oceans. He suggested that continental drift occurred like an icebreaker plows through sea ice ( Figure below). He thought the continents could cut through the ocean floor.

An icebreaking ship.

Other scientists didn't buy his idea. They thought that the continents would be much more deformed than they are.

Wegener believed that Africa and South America had once been joined. He had the evidence. But very few scientists accepted his idea. He needed a mechanism that they would accept.

Alfred Wegener died in 1930 on an expedition on the Greenland icecap. The continental drift hypothesis was put to rest for a few decades. Only when technology could provide even more evidence for continental drift did scientists look into the idea again. Technology also helped scientists to develop a mechanism for how continents could drift.

Further Reading

Magnetic Polarity Evidence for Continental Drift

Bathymetric Evidence for Seafloor Spreading

Magnetic Evidence for Seafloor Spreading

Seafloor Spreading Hypothesis

• Alfred Wegener said that the continents had been joined as a single landmass, which he called Pangaea.
• Wegener thought that Pangaea was together about 300 million years ago.
• Wegener could not develop a mechanism for continents moving through oceanic crust that other scientists would accept.
• Describe the continental drift hypothesis.
• Why did scientists reject Wegener’s idea? What was needed for them to accept it?
• What was Wegener's mechanism for drifting continents?

Explore More

Use the resource below to answer the questions that follow.

• What is uniformitarianism?
• What did Wegener write about in his book?
• What did Wegener think caused continental drift?
• Give specific examples of the response to Wegener's continental drift hypothesis.
• What did scientists learn after the war?

36 Continental Drift: founding block of the Plate Tectonics Theory

The continental drift hypothesis, the foundation of Plate Tectonics theory was developed in the early part of the twentieth century, mostly by Alfred Wegener who proposed that continents move around on Earth’s surface and that they were once joined together as a single supercontinent called Pangaea. His hypothesis did not stand a trial at that time because nobody could explain the mechanism of the movement of continental plates.

Only with discoveries of ocean structure in 1960-1970s scientists understood the mechanism of plate movement.

See below a short documentary about the discovery of Plate Tectonics theory.

The Continental Drift Idea

Figure 1. The continents fit together like pieces of a puzzle. This is how they looked 250 million years ago.

Alfred Wegener, a German climatologist, proposed that the continents were once united into a single supercontinent named Pangaea, meaning all earth  in ancient Greek . He suggested that Pangaea broke up long ago and that the continents then moved to their current positions. He called his hypothesis  continental drift.

Evidence for Continental Drift

Besides the way the continents fit together, Wegener and his supporters collected a great deal of evidence for the continental drift hypothesis.

• Identical rocks, of the same type and age, are found on both sides of the Atlantic Ocean. Wegener said the rocks had formed side-by-side and that the land had since moved apart.
• Mountain ranges with the same rock types, structures, and ages are now on opposite sides of the Atlantic Ocean. The Appalachians of the eastern United States and Canada, for example, are just like mountain ranges in eastern Greenland, Ireland, Great Britain, and Norway (figure 2). Wegener concluded that they formed as a single mountain range that was separated as the continents drifted.

Figure 2. The similarities between the Appalachian and the eastern Greenland mountain ranges are evidences for the continental drift hypothesis.

• Fossils of the seed fern  Glossopteris  were too heavy to be carried so far by wind.
• Mesosaurus  was a swimming reptile but could only swim in fresh water.
• Cynognathus  and  Lystrosaurus  were land reptiles and were unable to swim.

• Grooves and rock deposits left by ancient glaciers are found today on different continents very close to the equator. This would indicate that the glaciers either formed in the middle of the ocean and/or covered most of the Earth. Today glaciers only form on land and nearer the poles. Wegener thought that the glaciers were centered over the southern land mass close to the South Pole and the continents moved to their present positions later on.
• Coral reefs and coal-forming swamps are found in tropical and subtropical environments, but ancient coal seams and coral reefs are found in locations where it is much too cold today. Wegener suggested that these creatures were alive in warm climate zones and that the fossils and coal later had drifted to new locations on the continents.

Although Wegener’s evidence was sound, but most geologists at the time rejected his hypothesis of continental drift. Why do you think they did not accept continental drift?

Scientists argued that there was no way to explain how solid continents could plow through solid oceanic crust. Wegener’s idea was nearly forgotten until technological advances presented even more evidence that the continents moved and gave scientists the tools to develop a mechanism for Wegener’s drifting continents.

Magnetic Polarity Evidence

Figure 4. Earth’s magnetic field is like a magnet with its north pole near the geographic North Pole and the south pole near the geographic South Pole.

Puzzling new evidence came in the 1950s from studies on the Earth’s magnetic history (figure 4).

Scientists used  magnetometers , devices capable of measuring the magnetic field intensity, to look at the magnetic properties of rocks in many locations .

Magnetic Pole Moving?

Geologic Approach to Magnetic Pole Wandering

All igneous rocks have magnetite, a mineral consisting mainly of iron. Igneous rocks can be found in many parts of the world.

Magnetite  crystals are like tiny magnets that point to the north magnetic pole as they crystallize from magma. The crystals record both the direction and strength of the  magnetic field  at the time. The direction is known as the field’s  magnetic polarity.

Geologists noted important things about the magnetic polarity of different aged rocks on the same continent:

• Magnetite crystals in fresh volcanic rocks point to the current magnetic north pole  (figure 5) no matter what continent or where on the continent the rocks are located.

• Older rocks that are the same age and are located on the same continent point to the same location, different from the current north magnetic pole.
• Older rock that are of different ages do not point to the same locations or to the current magnetic north pole.

In other words, although the magnetite crystals were pointing to the magnetic north pole, the location of the pole seemed to wander.  Scientists were amazed to find that the north magnetic pole changed location through time (figure 6).

Figure 6. The location of the north magnetic north pole 80 million years before present (mybp), then 60, 40, 20, and now.

There are three possible explanations for this:

1. The continents remained fixed and the north magnetic pole moved.

2. The north magnetic pole stood still and the continents moved.

3. Both the continents and the north pole moved.

During studies of magnetism in various countries geologists noted that for rocks of the same age on different continents , the  magnets pointed to different magnetic north poles .

• 400-million-year-old magnetite in Europe pointed to a different north magnetic pole than the same-aged magnetite in North America.
• 250 million years ago, the north poles were also different for the two continents.

The scientists looked again at the three possible explanations. Only one can be correct.

If the continents had remained fixed while the north magnetic pole moved, there must have been two separate north poles.

Since there is only one north pole,   the only reasonable explanation is that the north magnetic pole has remained fixed but that the continents have moved.

To test this, geologists fitted the continents together as Wegener had done. It worked!

There has only been one magnetic north pole and the continents have drifted (see figure below). The view on this map is from the north down (polar projection).

The maps above show the polar wandering curve through Pangaea as well as through the present day configuration, which provides further evidence for moving tectonic plates.

This evidence for continental drift gave geologists renewed interest in understanding how continents could move about on the planet’s surface.

Lesson Summary

• In the early part of the 20th century, scientists began to put together evidence that the continents could move around on Earth’s surface.
• The evidence for continental drift included the fit of the continents; the distribution of ancient fossils, rocks, and mountain ranges; and the locations of ancient climatic zones.
• Although the evidence for continental drift was extremely strong, scientists rejected the idea because no mechanism for how solid continents could move around on the solid earth was developed.
• The discovery of apparent polar wander renewed scientists interest in continental drift.

Geology 101 for Lehman College (CUNY) Copyright © by Yuri Gorokhovich and Lumen Learning is licensed under a Creative Commons Attribution-NonCommercial-ShareAlike 4.0 International License , except where otherwise noted.

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Theory of Continental Drift: Causes and Evidence

If you take a look at a map of the earth today, you will see the current locations of broken land masses that constitute the earth. However, would you believe if someone told you that these broken land masses were once connected to each other as one huge supercontinent?  Well, this claim was made in the 90’s by Alfred Wegener , a German polar researcher, meteorologist and geophysicist who died in 1930.

Wegener’s theory of continental drift states that the existing continents of the earth were once glued together forming a super landmass. Over time, the landmass broke and drifted away and is still drifting to this day. In his proposal, he stated that the super content, which he named Pangaea, meaning ‘’all earth” once existed. The supercontinent was surrounded by water bodies, mainly oceans, and seas.

As a result of movement of the supercontinent, Pangaea split into two super landmasses namely Laurasia and Gondwanaland. Laurasia, makes up the northern continents of today. The northern continent consists of Europe, North America, and Asia. Gondwanaland makes up the southern continents of today. The southern continent consists of South America, Antarctica, Australia, India, and Africa. While making this claim, he had a collection of evidence to support it.

Causes of Continental Drift

The causes of continental drift are perfectly explained by the plate tectonic theory . The earth’s outer shell is composed of plates that move a little bit every year. Heat coming from the interior of the earth triggers this movement to occur through convection currents inside the mantle. Over the course of millions of year ago, this gradual movement caused the once combined supercontinent to separate into 7 continents you witness in the present day.

Almost all plate movement occurs in boundaries which lie between different plates. When plates drift away from each other, there is formation of new crust at divergent boundaries.  On the other hand, tectonic movement destroys crust during interaction of the plates. Destruction happens when one plate moves below the other at convergent boundaries. However, the crust is never destroyed when plates move past one another horizontally at transform boundaries.

Continental drift has impacted the universe in many ways.  It has affected the global climate, the world’s geographical positions and the evolution of animals. Continental drift also comes along with grave effects such as Volcanoes , Earthquakes, and Tsunamis . Through the theory of continental drift, humans have been able to figure out how the earth’s crust moves and the causes of volcanoes , earthquakes , oceanic trenches, formation of mountain ranges and other geological occurrences.

Evidence of Continental Drift Theory

Fossil plants and animals clue.

Fossils of creatures and plants discovered on different continents helped to him push his case that the continents were once locked together before breaking up and drifting away. Some of the fossil evidence discovered on the continents includes mesosaurus, lystosaurus, cygnognathus and glossopteris.

Mesosaurus are fossils originating from aquatic freshwater reptiles. These reptiles lived in freshwater bodies such as lakes and rivers. If you take a look at the map before the continents drifted away, you find that Mesosaurus is located in the southern parts of Africa and North America. If you look at the current map after the continents drifted away, you find that North America and Africa are far away from each other separated by the Atlantic Ocean .

So, his theory is proved by the fact that the freshwater reptiles could not swim across the ocean waters, hence, their distribution on every continent. The discovery of fossils on different continents indicated that the continents were once together before they drifted away.

• Lystrosaurus and Cygnognathus

Lystrosaurus is Fossil from land reptiles. Cygnognathus is Fossil from another species of reptile. If you look at the map before the continents drifted away, you find that Cygnognathus was situated in South America and Africa. Lystrosaurus, on the other hand, was located in Africa, India, and Antarctica. According to the Lystrosaurus and Cygnognathus’ body anatomy, they are not designed for swimming. Now, looking at the current map after drifting of the continents, Cygnognathus is situated in Africa and South America.

So, technically, the creature would not have traveled through the ocean to get to the next continent. The distribution of these reptiles in different continents proves that these separate land masses were once together before splitting. On top of that, Lystrosaurus is situated in Antarctica, India, and Africa according to the modern map. Again, for this creature to swim from Africa to Antarctica would have been impossible. So, the fact that these organisms could not swim through the vast water bodies helps to substantiate the fact that the continents were once together to allow distribution of these organisms in various continents where their fossils were found on.

• Glossopteris

Glossopteris was Fossil from fern. It is a fern that was discovered in Africa, South America, Antarctica, India, and Australia. According to the modern day map, these continents are far apart. It’s, therefore, impossible that the seeds of the fern were blown by wind or floated across the ocean to have that kind of population on these 5 continents . The fact that the seeds would have been unable to be blown or floated to these continents proves that these continents were once together.

Information from climate

Apart from fossil evidence, Wegener used climatic clues to substantiate his facts. One of the clues he used was the glacier. Wegener, in his expedition, discovered glacier grooves in all the continents. Glacier grooves are the gaping trenches or landmarks carved out by movement of glacier. He discovered glacier groves in continents that were not cold enough to support snow formation in the present day. When he brought these continents together, the glacier grooves perfectly matched up. This suggested that these continents were once together and drifted away over time.

The perfect fitting of continents

Wegener also provided evidence of continental drift by looking at the physical shape of continental coastlines. The shape of continental coastlines visibly matched up like pieces of the puzzle. For example, the continents of South America and Africa fit perfectly when brought together. This indicates that the continents were once fixed together and drifted apart over time.

Wegener specifically used rock composition and mountain ranges to provide evidence of continental drift. He provided evidence that mountain ranges occurring on opposite continents matched up pretty well when brought together. This perfect aligning of mountain ranges indicated that the continents were once together. For example, if you take the mountains ranges of North America and Europe, they align perfectly well. Mountains are typically formed when two opposite land masses collide with each other triggering the rock found at the point of collision to fold or bulge upwards.

In terms of rock composition, at locations where continents match up, the kinds of rocks on the opposite sides of the continents were of the same kind. Since these match up points consisted of the same kind of rock further proves that the continents were once together before breaking away and drifting.

Despite Wegener’s effort to try to prove his theory of continental drift, it was never accepted. When he was tasked with proving how these continents moved to different places, he couldn’t. However, this theory of continental drift came to be accepted in the 90’s after his death. He died of an alleged heart attacked when on an expedition to Greenland.

Photo by: pixabay

I am Sonia Madaan, a mother with a passion for science, computing, and environmental issues. Motivated by my passion and education, I started a website to spread awareness about climate change and its causes, like rising greenhouse gas levels. You can read more about me here .

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Alfred Wegener: Building a Case for Continental Drift

Continental Drift

The Theory of Continental Drift is defined as the movement of the Earth’s continents relative to each other, thereby appearing to drift together across the oceanic bed. Although Alfred Wegener was able to produce a viable hypothesis with evidence and specifically state the theory, it should be noted there were previous geologists and scientists who thought similar to Wegener. For example, between 1889 and 1909 Roberto Mantovani speculated that all continents had once been conjoined in a “supercontinent,” and even developed an expanding Earth hypothesis.

A depiction of the continents joined together as the “supercontinent,” Pangea, and the path that led them to the positions they reside in today.

Alfred Wegener’s curiosity toward the possibility of continental drift came in 1910 after he noticed how Earth’s continents resembled pieces of a jigsaw puzzle. For example, he noted how South America coast correctly lined up with the coast of Northwest Africa. It wasn’t until 1911, when Wegener came across several scientific documents listing fossils of identical plants and animals found on opposite sides of the Atlantic that his passion for the subject truly showed. Reflecting on this monumental moment in his life, he wrote, “A conviction of the fundamental soundness of the idea took root in my mind.” Alfred Wegener knew massive amounts of evidence needed to be collected in order to justify such a fantastic idea—because with no practical driving force behind it the theory loses most of its credit. In order to maximize evidence for his theory and overlook the absence of a mechanism, he decided to draw from a variety of scientific fields including geology, geography, biology, and paleontology.

• What is Continental Drift?

Continental drift is a phenomenon which explains how the earth’s continents move on the surface of the ocean bed. Abraham Ortelius was the first geographer who proposed this phenomenon in 1596. The theory was independently developed in 1912 by Alfred Wegener, but it was rejected due to lack of mechanism (which was introduced by Arthur Holmes). The continental drift theory was replaced by the plate tectonic theory which illustrates how the continents drift.

The Continental Drift Theory

The hypothesis of continental drift was developed during the early parts of the twentieth century by Wegener. He believed that all eight continents were once a single supercontinent before separating. A number a geologists denounced his hypothesis after he published it in his book about the origin of oceans and continents in 1915. One of the reasons is that his theory had no credible mechanism. Another problem with Wegener's proposal was the fact that he stated that the velocity of continental drift was 8.202ft/year which is quite high (currently the acceptable rate of continental drift is 0.082ft/year). Wegner was a geographer and not a geologist, and other geologists believed that he did not have sufficient evidence.

Although his observations about the rocks and fossils were correct, Wegener was wrong on various issues. He believed that the continents plowed through the crust of the ocean. Even though the continental drift hypothesis was discarded, it did help introduce the idea of continental movement in geosciences. Decades later, various geologists confirmed some of his ideas including the existence of a super-continent known as Pangaea. Pangaea is believed to have been formed about 250 million years ago.

One of the outstanding questions which Wegener failed to answer was what type of forces propelled the earth’s plates, and this resulted in his hypothesis being opposed by many scientists. Later, a British geologist known as Arthur Holmes championed this theory. In 1931 Holmes proposed that the mantle of the earth has some convention cells which dispersed radioactive heat which drifted the earth’s crust. Jack Oliver provided the seismologic proof which supports the idea of plate tectonic that replaced continental drift in an article which he published in 1968.

Evidence of Continental Drift

Some of the evidence supporting the continental drift of the tectonic plates include the presence of similar animals and plant fossils on the shores of various continents, which suggest that they were once joined. Fossils of a freshwater reptile known as Mesosaurus was found both in South Africa and Brazil. Another piece of evidence is of the discovery of the fossils of Lystrosaurus (a land reptile) on rocks of the same age in Antarctica, India, and Africa. Some of the existing evidence includes numerous earthworm families like Octochaetidae and Acanthodrilidae which are indigenous to both in Africa and South America. The complementary arrangement of the facing sides on Africa and South America is also another evidence which supports the idea of continental drift.

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5.1: Alfred Wegener’s Continental Drift Hypothesis

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Alfred Wegener’s Continental Drift Hypothesis

Alfred Wegener (1880-1930) was a German scientist specializing in meteorology and climatology. His knack for questioning accepted ideas started in 1910 when he disagreed with the explanation that the Bering Land Bridge was formed by isostasy and that similar land bridges once connected the continents. After reviewing the scientific literature, he published a hypothesis stating the continents were originally connected and then drifted apart. While he did not have the precise mechanism, his hypothesis was backed up by a long list of evidence.

Early Evidence for Continental Drift Hypothesis

Wegener’s first evidence was that some continents’ coastlines fit together like pieces of a jigsaw puzzle. People noticed the similarities in the coastlines of South America and Africa on the first world maps, and some suggested the continents had been ripped apart. Antonio Snider-Pellegrini did preliminary work on continental separation and matching fossils in 1858.

Snider-Pellegrini’s map showing the continental fit and separation, 1858.

What Wegener did differently was synthesizing a large amount of data in one place. He used true continents’ edges based on the continental shelves’ shapes. This resulted in a better fit than previous efforts that traced the existing coastlinesWegener also compiled evidence by comparing similar rocks, mountains, fossils, and glacial formations across oceans. For example, the fossils of the primitive aquatic reptile Mesosaurus were found on the separate coastlines of Africa and South America. Fossils of another reptile, Lystrosaurus, were found in Africa, India, and Antarctica. He pointed out that these land-dwelling creatures could not have swum across an ocean.

Image showing fossils that connect the continents of Gondwana (the southern continents of Pangea).

Opponents of continental drift insisted trans-oceanic land bridges allowed animals and plants to move between continents. The land bridges eventually eroded, leaving the continents permanently separated. The problem with this hypothesis is the improbability of a land bridge being tall and long enough to stretch across a broad, deep ocean.

More support for continental drift came from the puzzling evidence that glaciers once existed in normally very warm areas in southern Africa, India, Australia, and Arabia. Land bridges could not explain these climate anomalies. Wegener found similar evidence when he discovered tropical plant fossils in the frozen region of the Arctic Circle. As Wegener collected more data, he realized the explanation that best fit all the climate, rock, and fossil observations involved moving continents.

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How Did Continental Drift Affect Life On Earth Today?

Tectonic plates, moving continents, the effects of continental drift.

As the continents eventually drifted apart, some creatures that lived in places where the continents separated started to become different from each other. Countless different related species are the result of continental drift.

The first evidence of life on Earth can be seen as far back as 3.7 billion years ago, which is an unimaginable amount of time. However, life has changed a lot since then. Along with changes to living creatures, there have also been changes in how the Earth looks.

A better way to put it is that there have been changes in living creatures caused by the changes that happened to the Earth.

But what exactly are these changes that affected the planet?

The existence of mountains, the course of rivers, and the width of valleys have all changed and shifted over time, but in this article, we’re talking about even bigger changes. We’re going to talk about changes that gave the Earth its completely new faces over the course of history. We’re going to talk about continental drift!

Recommended Video for you:

Earth may look like one giant block of solid rock, but only some of it is solid and only some of it is rock.

Earth is made of many puzzle-like pieces called tectonic plates. The reason we know about this is because the west coast of Africa and the east coast of South America fit together like puzzle pieces. This is what led Alfred Wegner to first come up with the continental drift theory.

Then Wegner noticed something else that gave even more strength to his theory. Multiple fossils from opposite sides of the Atlantic Ocean showed similarities to one another. The only way this could be possible is if those places had once been joined together.

But how is it possible for a whole continent to move?

Also Read: What Is The Continental Drift Theory And How Is It Related To Plate Tectonics?

The Earth’s tectonic plates are part of the uppermost layer, called the crust. There are about 15-20 of these plates and they’re made of solid rock. But how does solid rock move around? Well, the crust rests on a layer of molten rock called the mantle, which is almost 3000 kilometers thick. Being that big, it has its own processes.

Radioactive processes take place within the mantle and cause the release of heat. The release of this heat happens unevenly and creates a conventional current. This means that there is a flowing current in the liquid mantle created by different temperatures. This flowing current is what causes the tectonic plates to move. You can read more about that phenomenon here .

This causes the different plates to move at an average rate of 1.5 cm a year. This may not seem like much, but it makes a huge difference when you think about the age of Earth.

Also Read: What Are Subduction Zones?

Continental drift has played a large role in the evolution of life today. It has caused some very unique creatures to evolve from very different ancestors. It has also caused some species from the same place to diverge into many separate species.

Carried Across The Ocean

Have you seen the silly scenes from Ice Age: Continental Drift where Manny, Sid and Diego float on a small piece of land across the ocean? The idea may seem ridiculous, but in the grander scheme of things, it’s actually a comical and satirical depiction of what really happened.

The world once had a single large continent called Pangea. A single ocean, which we now call Panthalassa,  surrounded the whole continent. This was around 250 million years ago. Life has existed on Earth for 3.5 billion years, and complex life with large creatures and complex ecosystems has been around for 540 million years. This means that the Earth had lots of wildlife before the continents began drifting apart.

As the continents eventually separated, some creatures that lived in places where the continents broke started to become different from each other.

Marsupials are a great example of different species that formed due to continental drift. Marsupials are pouched mammals, like kangaroos and koalas, but did you know about their famous American cousins, the opossums?

Well, believe it or not, but marsupials originally existed in America. At the time, all the southern continents were a part of one giant landmass called Gondwanaland. Eventually, as Gondwanaland split, the marsupials in Australia evolved to form pouches, while opossums evolved without very evident pouches (they do have tiny flaps, but they’re not nearly as prominent).

This is just one example. Anteaters on different continents have diverged only because of continental drift. On the flip side, the purple pig-nosed frog, which exists in India, has its closest ancestors in Madagascar, as that’s where it originated from before being carried away on the Indian subcontinent to Asia.

Creating Barriers

During the movement of tectonic plates, land masses did not just drift apart. There are some land masses that also crashed into each other. When these land masses crashed into each other, they formed mountains. An example of this is the ongoing formation and rise of the Himalayas.

When these mountains formed, they created barriers of separation. This means that some members of the same species were separated on either side of the mountain. In a similar way to how species diverge because of being carried away across water bodies, new species are also formed by the formation of mountains. You can read about those types of speciation events in the article here .

Continental drift is an ongoing process. Although we will never see measurable changes from it during our lifetime, it has directly influenced life on Earth today. By studying this process further, we should be able to predict how the face of the Earth will continue to change life on this planet in the future.

• Alfred Wegener: Building a Case for Continental Drift. The University of Illinois Urbana-Champaign
• Early Life on Earth – Animal Origins. The Smithsonian Institution
• What is the relation between continental drift and the evolution? How four very different kinds of ant/termite eaters could occur in India, Africa, South America, and Australia? - UCSB Science Line. The University of California, Santa Barbara
• What is a tectonic plate? [This Dynamic Earth, USGS]. The United States Geological Survey
• Introduction to geology : Read, H. H. (Herbert Harold), 1889-1970 : Free Download, Borrow, and Streaming : Internet Archive - archive.org
• What is Tectonic Shift? - NOAA's National Ocean Service. The National Ocean Service
• Plate tectonics and lava lamps - NOAA. The National Oceanic and Atmospheric Administration
• Biju, S. D., & Bossuyt, F. (2003, October). New frog family from India reveals an ancient biogeographical link with the Seychelles. Nature. Springer Science and Business Media LLC.

Mikhail Nazareth has a Bachelor’s degree in Chemistry, Botany and Zoology from Christ University, Bangalore. He is currently pursuing his Master’s of Marine Biology at James Cook University, Townsville, Australia. He loves exploring the wild and all the creatures in it. When he’s not crawling through forest shrubberies or looking into tidepools, he’s probably playing ultimate frisbee or jamming with his friends.

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Uncover Alfred Wegener's theory of continental drift through biological and geological evidence and the theory of plate tectonics

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Scientists uncover hidden forces causing continents to rise

Scientists at the University of Southampton have answered one of the most puzzling questions in plate tectonics: how and why 'stable' parts of continents gradually rise to form some of the planet's greatest topographic features.

They have found that when tectonic plates break apart, powerful waves are triggered deep within the Earth that can cause continental surfaces to rise by over a kilometre.

Their findings help resolve a long-standing mystery about the dynamic forces that shape and connect some of the Earth's most dramatic landforms -- expansive topographic features called 'escarpments' and 'plateaus' that profoundly influence climate and biology.

The new research, led by the University of Southampton, examined the effects of global tectonic forces on landscape evolution over hundreds of millions of years. The findings are published today (07/08/2024) in the journal Nature .

Tom Gernon, Professor of Earth Science at the University of Southampton and lead author of the study said: "Scientists have long suspected that steep kilometre-high topographic features called Great Escarpments -- like the classic example encircling South Africa -- are formed when continents rift and eventually split apart. However, explaining why the inner parts of continents, far from such escarpments, rise and become eroded has proven much more challenging. Is this process even linked to the formation of these towering escarpments? Put simply, we didn't know."

The vertical motions of the stable parts of continents, called cratons, remain one of the least understood aspects of plate tectonics.

The team from the University of Southampton, including Dr Thea Hincks, Dr Derek Keir, and Alice Cunningham, collaborated with colleagues from the Helmholtz Centre Potsdam -- GFZ German Research Centre for Geosciences and the University of Birmingham to address this fundamental question.

Their results help explain why parts of the continents previously thought of as 'stable' experience substantial uplift and erosion, and how such processes can migrate hundreds or even thousands of kilometres inland, forming sweeping elevated regions known as plateaus, like the Central Plateau of South Africa.

Linking diamonds with landscape evolution

Building on their study linking diamond eruptions to continental breakup, published last year in Nature , the team used advanced computer models and statistical methods to interrogate how the Earth's surface has responded to the breakup of continental plates through time.

They discovered that when continents split apart, the stretching of the continental crust causes stirring movements in Earth's mantle (the voluminous layer between the crust and the core).

Professor Sascha Brune, who leads the Geodynamic Modelling Section at GFZ Potsdam, said: "This process can be compared to a sweeping motion that moves towards the continents and disturbs their deep foundations."

Professor Brune and Dr Anne Glerum, also based at Potsdam, ran simulations to investigate how this process unfolds. The team noticed an interesting pattern: the speed of the mantle 'waves' moving under the continents in their simulations closely match the speed of major erosion events that swept across the landscape in Southern Africa following the breakup of the ancient supercontinent Gondwana.

The scientists pieced together evidence to propose that the Great Escarpments originate at the edges of ancient rift valleys, much like the steep walls seen at the margins of the East African Rift today. Meanwhile, the rifting event also sets about a 'deep mantle wave' that travels along the continent's base at about 15-20 kilometres per million years.

They believe that this wave convectively removes layers of rock from the continental roots.

"Much like how a hot-air balloon sheds weight to rise higher, this loss of continental material causes the continents to rise -- a process called isostasy," said Professor Brune.

Building on this, the team modelled how landscapes respond to this mantle-driven uplift. They found that migrating mantle instabilities give rise to a wave of surface erosion that lasts tens of millions of years and moves across the continent at a similar speed. This intense erosion removes a huge weight of rock that causes the land surface to rise further, forming elevated plateaus.

"Our landscape evolution models show how a sequence of events linked to rifting can result in an escarpment as well as a stable, flat plateau, even though a layer of several thousands of meters of rocks has been eroded away," explained Jean Braun, Professor of Earth Surface Process Modelling at GFZ Potsdam, also based at the University of Potsdam.

The team's study provides a new explanation for the puzzling vertical movements of cratons far from the edges of continents, where uplift is more common.

Dr Steve Jones, Associate Professor in Earth Systems at the University of Birmingham, added: "What we have here is a compelling argument that rifting can, in certain circumstances, directly generate long-lived continental scale upper mantle convection cells, and these rift-initiated convective systems have a profound effect on Earth's surface topography, erosion, sedimentation and the distribution of natural resources."

The team has concluded that the same chain of mantle disturbances that trigger diamonds to quickly rise from Earth's deep interior also fundamentally shape continental landscapes, influencing a host of factors from regional climates and biodiversity to human settlement patterns.

Professor Gernon, who was awarded a major philanthropic grant from the WoodNext Foundation, administered by Greater Houston Community Foundation, to study global cooling, explained that continental breakup disturbs not only the deep layers of the Earth but also has effects that reverberate across the surface of the continents, previously thought to be stable.

"Destabilising the cores of the continents must have impacted ancient climates too," concluded Professor Gernon.

• Earth Science
• Early Climate
• Origin of Life
• Ancient Civilizations
• Plate tectonics
• Mid-ocean ridge
• Oceanic trench
• Mantle plume
• San Andreas Fault

Story Source:

Materials provided by University of Southampton . Note: Content may be edited for style and length.

Journal Reference :

• Thomas M. Gernon, Thea K. Hincks, Sascha Brune, Jean Braun, Stephen M. Jones, Derek Keir, Alice Cunningham, Anne Glerum. Coevolution of craton margins and interiors during continental break-up . Nature , 2024; 632 (8024): 327 DOI: 10.1038/s41586-024-07717-1

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