You have learned that the movement of the tectonic plates causes natural disasters, such as earthquakes and volcano eruptions. But these movements also form various landforms. Yes, the landform on which we live is also the result of the movement of continental plates. You might ask what does a continental collision form? Never worry. In this article, you will learn about what landform is created when two continental plates collide.
1. What Landform is created when Two Continental Plates converge? What does a Continental Collision form? What Kind of Landform is created at Convergent Plate Boundaries?
The process of continental convulsion causes the formation of mountains. This process, termed as progeny, takes millions of years to happen.
When two tectonic plates are pushed together, fold mountains are formed. So, the answer to what does a continental collision form is orogeny. In this process, all the debris gets folded, including the Earth’s crust. This gets warped into the formation of folded mountains. So, if you wonder, what landform is created when two continental plates collide, it is the fold mountains, which are the most common type of mountains found on the Earth’s surface. (See What is the Difference between Oceanic Crust and Continental Crust?)
2. What Type of Mountains are formed when Two Plates collide?
You may also ask, what landform is created when two continental plates collide? When two continental plates collide, fold mountains are formed. This can be explained using the tablecloth experiment. When you simultaneously push the ends of a neatly spread tablecloth from both sides, it forms a crest. In honor of this experiment, a crucial part of fold mountains is named nappes, derived from the French word Nappe, meaning tablecloth.
The phenomenon is easy to understand, but the only difference is that in the experiment, the folding of the tablecloth doesn’t cause any difference to the table. But, in the case of fold mountains, the Earth’s crust also gets folded, and from space, it looks as though the fold mountains are wrinkles on Earth’s crust. (See Why do Shield Volcanoes have Weak Eruptions?)
3. The Himalayas were made when these Two Plate Types converged?
The Himalayas have always acted as a natural protector of India since ancient times. They saved India from several foreign invasions as it was practically impossible to cross them and enter India. Let’s learn what does a continental collision form or the formation of the Himalayas.
- About 240 million years ago, the entire landmass of the Earth was a single supercontinent called Pangea.
- A single water body surrounded the supercontinent called the Panthallasic ocean.
- There are 7–8 tectonic plates on the Earth’s surface.
- When the crust began to form cracks on itself, it formed the boundaries of a series of tectonic plates.
- Pangea broke into two supercontinents: Gondwana Land, the Southern continent, and Laurasia, the Northern continent.
- Breaking up further, Laurasia broke into Asia, Europe, and North America. Similarly, Gondwana Land broke into South America, Africa, Antarctica, and Australia.
- It is interesting to know that India was not a part of the Northern Supercontinent Laurasia. It belonged to the Gondwana Land. Later, it got attached to Africa and Australia.
- India broke further and collided with the area belonging to present-day Ladakh. The collision gave birth to the Himalayas.
So, to answer what landform is created when two continental plates collide, note that the lighter plate rises, causing mountains to form or increasing the heights of mountains. The heavier ones get pushed under the surface of the Earth. The tectonic plates are still in a collision today, because of which the Himalayas are still increasing in height, making Nepal an earthquake-prone zone. Due to this reason, the Himalayas are known as young fold mountains. (See How are Earthquakes Distributed on the Map?)
4. Examples of Landforms created by Plate Tectonics
Any relief feature or landscape specific to an area, chiefly formed due to subsistence or uplift of Earth’s crust are an example of what landform is created when two continental plates collide. The landforms thus created are rift valleys, plateaus, and fold mountains.
- Rift Valleys: West Antarctic Rift, Baikal Rift Valley, Rio Grande Rift, The East African Rift Valley, etc.
- Plateaus: The Yellowstone Plateau in the United States, Deccan Plateau, Chhota Nagpur Plateau in India, etc.
- Fold Mountains: Aravalli Ranges and Himalayas in India, the Alps in Europe, the Andes in North America, etc.
5. What occurs when Two Oceanic Plates move away from Each Other?
While asking what landform is created when two continental plates collide, you might ask about the consequences when oceanic plates move away. When two tectonic plates move apart, a divergent boundary occurs. Along these boundaries, the Earth’s molten rock material, magma, rises from its mantle layer. This magma solidifies to create a new oceanic crust. For example, the Mid-Atlantic Ridge is located in the Atlantic Ocean and is one of the longest mountain ranges in the world. It is a classic example of a divergent boundary. (See What Layer of the Earth does Magma come from?)
6. What Kind of Landform is created when Two Continental Plates diverge?
Similar to the question of what landform is created when two continental plates collide, a question arises when two continental plates diverge. The movement of tectonic plates causes them to drift apart, thus causing a crest to develop. Thus, the gap created is filled by magma that rises from the mantle layer. The magma is spread to both sides by ocean currents. It solidifies, and a new landform is created. This process takes millions of years. (See How Convection Current causes the Lithospheric Plate to move?)
7. How were the Appalachians formed?
The Appalachian Ranges are the oldest fold mountains. The highest peak, Mount Mitchell, is 6,684-foot and is located in North Carolina. Compared to the Himalayas, the erosion process and weathering of the Appalachians happened approximately 200 million years ago. The Atlantic Coastal Plains’ strata are made up of transportation, deposition, and weathering. Must read Desert and Steppe Lands Percentage.
The geological history of the Appalachians can be divided into several progenies:
- Grenville Orogeny: The supercontinent Rodinia came into existence. Its collision formed the core of the Appalachians: metamorphic and igneous rocks. By 750 million years ago, Rodinia broke up; 640 million years ago, the ocean Iapetus flowed between these two continents.
- Taconic Orogeny: Around 460 million years ago, a volcanic chain arc collided with the continent of North America and caused the Iapetus Ocean to close. This collision caused the formation of Taconic ranges in New York.
- Acadian Orogeny: When the Avalonian Terrain collided with North American Craton 375 million years ago, it did so in the northern part. It then slowly moved southward. Through geological research, it is also evident that the aforesaid collision took place several times with varying collision forces.
- Alleghenian Orogeny or Appalachian Orogeny: Alleghenian orogeny occurred approximately 325 million years ago. It was the cause of the formation of Pangea. The African and North American continents collided, which formed Central Pangean Mountains. The Anti-Atlas Mountains, situated in North-Western Africa, were a part of the Central Pangean Mountains before they drifted apart. These landmasses continue to drift even today. Must See What body of Water connects Gulf of Mexico and Caribbean?
8. How were the Rocky Mountains formed?
Another way to respond to what landform is created when two continental plates collide is the formation of the Rocky mountains which is given below:
- From Montana to southward, the Rocky Mountains, or the Rockies, are made from ancient granite that is 1.5 billion years old. Granite makes up the major part of the continent, so geologists call it the basement.
- The Canadian Rockies were formed of sedimentary rocks piled up on top of continental foundations. But we find granite in the Northern Rockies too.
- Mountains are usually formed near tectonic plate boundaries, but the southern part of the Rocky Mountains is far from the plate margin. The front range in Colorado is 1069.34 km away from the place where the Pacific and North American tectonic plates meet.
- Geologists suggest that the subducting plate of the Pacific Ocean is responsible for this. The ocean crust was pushed deep beneath North America’s mantle for 100 million years when an unusual activity happened. The tectonic plate started to subduct at a shallow angle instead of rising steeply, like a spatula under a pancake. This event took place 68 million years ago.
- The tectonic plate slid under North America horizontally. During this event, it put the plates under compression because they are pushed at the end and scraped at the bottom. So, it squeezes, pushes up the mountains, and transfers this mountain building from the edge to a long distance away from the plate margin. This caused the Rocky Mountains to sprout from the ground.
- The ocean plate scraped along the underside of North America for millions of years. It created friction, which caused the breaking up of the basement granite of the North American plate, and punched it upward. The shallow angle trajectory at the Pacific Ocean plate explains why these mountains were formed so far inland and why it contains granite.
The Rocky Mountains of the south are broken granite, which thrusts up through layers of sedimentary rocks. Red Rocks Park, Denver, Colorado, is the best example of a landscape forged by granite uplift. The granite mountains here were pushed up by 6 km. On top of the granite lie red slabs of rock known as flat irons. The sedimentary rocks that once blanketed the entire granite basement are the patchwork remains now. I hope all this information regarding the formation of mountains and what landform is created when two continental plates collide is cleared now. (Also read What is the Importance of Geography?)