Continental Drift Theory

Distribution of oceans and continents

The position of the ocean and continents today is not the same as it is today, changes have taken place. The Atlantic Ocean coastline noticed kelyvr felt someone has split in two. (See Symmetry) Can this be called a coincidence? After seeing such symmetry, many scientists/geographers made maps, and they observed and said there could be a possibility. Looking at the coastline of the Atlantic Ocean, it can be said that in the past, North America and South America, Europe, and Africa could have been connected because it looks like symmetry, it gives evidence/shows possibility.

1. Abraham Oreelisus (Dutch map maker)

Abraham oreelisus was a cartographer whose job was to make a map, he made a world map, he said in 1596 that South America, North America, Europe, and Africa may have been together in the past.

2. Antonio Pellegrini (Cartographer)

It supports the theory of Alfred Wegener, it also supports that argument and says that there is a possibility of 3 continents being connected. He made a map that showed the 3 continents together and said it could be possible.

3. Alfred Wegener (German metrologist)

After working further on this theory, he realized that continental drift is happening, Wegner says that the continents were joined together before. He presented a comprehensive argument for the continental drift theory. (1912/1920)

The seafloor is made up of ridges, trenches, and sea mounts.

There are some currents of ambient circulation,

1. Lithosphere

2. Hydrosphere 

3. Core

The drift of the plates relative to each other, which is determined by how far another plate is moving, and how far or near which plate is, is called the theory of continental drift

Polar wandering

In plate tectonics, it is known as plate tectonic theory which states that the plates move due to the currents that have been created.

Some views of F.B.Taylor:

FB Taylor introduced his concept of ‘horizontal displacement of continents’ in 1908. An important objective of his hypothesis was to explain the origin and relative distribution of folded mountains on the Earth’s surface. He wanted to explain the north-south arrangement of the Rockies and Andes Mountain ranges and the east-west extension of the Alpine Mountains. Taylor postulated that during the Cretaceous period, there were two landmasses, (Laurasia and Gondwana) that were near the North and South Poles.

Assumption of Theory (by Taylor)

• The continents had moved towards the equator and had become sial.
• Tidal power is the main force behind the continent’s flow.
• Continents were displaced in two ways, equatorward and westward.

Continental drift theory- (Alfred Wegner)

This theory was proposed by Alfred Wegener in 1912/1920. He presented this theory in the book continental drift theory 1912/1920. At first there was only one large landmass, Pangaea. And this plot was surrounded by one sea that is Panthalassa. 200 million years ago Pangea began to break apart, in different directions. The period when Pangea began to break up is called the carboniferous period. In the Carboniferous Laurasia North (upper part) and Gondwanaland (lower part) The breakup of Pangaea into the above two parts, the force causing splitting is – Due to Earth’s rotation, pole flying force and buoyancy forces created.

Pole flying force is the centrifugal force of the earth due to the rotation of the earth or the rotation of the earth, we call it the centrifugal force, which is on the opposite side of gravity and causes the Pangea break. And buoyancy force means, when a ship is placed on water, the ship floats, that is the buoyancy force of that water.

The internal force of the water is trying to push up the weight of the ship and that buoyancy force caused the water to break up the panthalasa ocean.

• The power of the waves is also responsible for this.
• Power of waves.
• Gravitational force.
• Due to the motion of the sea towards the west.
• Earth rotates from west to east, so whatever tides occur in the oceans are east and west.
• Tides and ebbs in the ocean are caused by the moon and the sun.
• The bulge at the equator is because the earth is not round.
• Decreased centrifugal force at the pole.
• The centrifugal force increases as we move from the poles to the equator.
• Centripetal force is at the equator, so the pole which is there sometimes leaves its place and it is called pole flying force.
• Tethys Sea is a part of Panthalassa.
• Between Pangea and Gondwana, there is an ocean named Tethys.

Assumption of Alfred Wegener (by Alfred Wegener)

• The oceanic crust formed from Sima.
• A continent mass formed from Sial.
• A continental mass floats on the tectonic crust.
• In the Carboniferous period, there was a huge, united landmass, named Pangea. And that landmass was surrounded by water body called Panthalassa.

Evidence

• Polar wandering (shifting pole).
• Botanical evidence
• India, Australia, South Africa, Antarctica etc. were separated from Gondwana.
• Glossopteris is an explanation for the presence of the plant.
• Distribution of Fossils
• There was an animal called lamerus and meso that still exist today.
• A coherent landmass connecting the three parts was named Lumaria, named after the plant lemars,
• Rocks of the same age
• Sedimentary mineral deposits
• There are gold rocks on the Brazilian plateau.

A drawback of Continental Drift Theory

• What during the conduction Mezoic period?
• The theory is not about the sea.
• Just logic.
• Wave force, gravitational force, and wave force is not that much powerful.

Conclusion

The theory of continental drift, proposed by Alfred Wegener in 1912/1920, suggests that the continents were once part of a single large landmass called Pangaea, which began to break apart about 200 million years ago. Wegener presented this theory in his book “Continental Drift Theory” in 1912/1920. He suggested that the continents moved towards the equator and became sial (continental crust), and the oceanic crust formed from sima. He also proposed that the continents floated on the tectonic crust and were displaced in two ways: equatorward and westward.

Wegener proposed several pieces of evidence to support his theory of continental drift. These included polar wandering, which showed shifting of the poles over time; botanical evidence, such as the distribution of plant fossils like glossopteris that were found in different continents but could have only grown in a unified landmass; and the distribution of fossils and animals like lamerus and meso that existed in different continents but had similarities.

Wegener also suggested that various forces, such as the Earth’s rotation causing centrifugal force or pole flying force, the motion of the sea towards the west, gravitational force, and the presence of tides and ebbs caused by the moon and the sun, played a role in the breakup of Pangaea. He also pointed out the presence of ridges, trenches, and sea mounts on the ocean floor, as well as the concept of lithosphere, hydrosphere, and core in the Earth’s structure.

Although Wegener’s theory of continental drift was initially met with skepticism and faced challenges, it laid the foundation for the modern theory of plate tectonics, which is widely accepted today. Plate tectonics explains the movement of the Earth’s lithosphere (made up of several large plates) on the semi-fluid asthenosphere below, and how this movement is responsible for the distribution of continents, formation of mountains, earthquakes, and volcanic activities. The concept of continental drift has revolutionized our understanding of the Earth’s geology and has led to significant advancements in the field of geosciences. So, while there were several scientists and cartographers before Wegener who observed and suggested the possibility of continents being connected based on the symmetry of coastlines and other evidence, it was Wegener’s comprehensive argument and evidence that formed the basis of the theory of continental drift. Overall, the theory of continental drift has greatly contributed to our understanding of the Earth’s history and continues to be a fundamental concept in geology and geosciences. It has also paved the way for further research and exploration of the Earth’s dynamic processes and continues to be an important area of study in modern geosciences.