The brain behind this post is to help us understand what happens when two oceanic plates collide. As you already know, plate movements are a popular topic. The reason is they have created most of the features we see on our planet, including ocean floors. So, this topic is essential.
Now here is what could happen when two oceanic plates collide:
When two oceanic plates collide, their densities help to determine the one that will appear on top of the other. And as you already know, the oceanic crust does become denser and colder when it spreads out of the mid-ocean ridge. So, when two oceanic plates conveying oceanic crust collides at a trench, the denser one will come under the less dense plate.
That is what happens when oceanic plates meet. You can read further for more information on this topic.
Oceanic Plate: What Does It Imply?
An ocean plate can also be referred to as a tectonic plate. And they appear at the bottom of the ocean. We also have two primary types of tectonic plates. One is oceanic, and the other is the continental.
At the convergent boundaries, these two plates meet. What transpires when they collide helps to decide the plate type. And remember, the two plates interacting are oceanic and continental.
So, at these convergent boundaries, what happens is that continental and oceanic plates collide. But when this happens, the one that is denser bends and pulls under the lighter and thicker one. Another term for this is “subducted.”
Let’s go back to what happens when plates collide. Usually, the oceanic crust is way thinner and denser than the continental crust. The continental crust is thicker and lighter. So when they collide, the lighter one has to come under the thicker one.
This event also generates what is known as the subduction zone. The oceanic crust will continue to sink deeper and deeper. And as this continues to happen, a valley or a much deeper oceanic trench develops.
Forcing the oceanic crust deeper into planet earth will result in the release of trapped gases and water. It happens, owing to high pressure and heat, as the oceanic crust makes its way into the earth.
At some point, the crust’s base would melt, thus forming what is called “magma.” The magma then increases in size and rises towards the surface of the earth and creates volcanoes.
Oceanic Plates Collision: Tectonic Plate Types
Tectonic plates are classified into major, minor, and micro. But the two main types of tectonic plates differ with regards to their composition. They are the continental and oceanic crust. And as I earlier said, the continental crust is light and thicker, while the oceanic crust is thinner and denser.
Another thing you should know about tectonic plates is that they form distinct boundaries when they collide. These include divergent, transform, and convergent. Many unpleasant things can also occur at these boundaries, which make the idea of them developing a scary one.
Their formation can create an earthquake, volcanic eruption, and even Orogeny.
Now back to the tectonic plates, we have different plates in the entire world. They are also classified into; major, minor, and micro plates, according to their respective sizes.
So, for better understanding and to gain more useful knowledge, let’s look at the various tectonic plate types we have.
1. The Pacific Plate
Remember the “Ring of Fire,” or maybe you are just hearing the name for the first time. Well, the Pacific tectonic plate hosts it. This plate has a size of approximately 103,300,000 square kilometers.
As the name implies, it also occurs in the Pacific Ocean, and down below. Another exciting thing you should know about the Pacific plate is that it stands as the largest among all tectonic plates.
Again, all the Pacific plate comprise of the oceanic crust. The only exception is the one around part of California and New Zealand. It is also a major tectonic plate based on its size.
2. The North American Plate
The next tectonic plate after the Pacific plate (in terms of size) is the North American plate. And for the records, it is the second-largest in size, in the whole world. It also comprises of the two plate types (oceanic and continental crust).
This North American plate measures approximately 75,900,000 sq km in size. Its continental crust also comprises of some of Iceland and North America. But there are things about this plate I would like to state clearly.
The first is that it is responsible for many events. One of them is the creation of the famous Mid-Atlantic Ridge. And as you know, this Ridge comprises of a mountain chain that sits in the Atlantic Ocean, down below.
A couple of hot spots that surfaced below this plate have also been linked to active seismic activities. One of them is the Yellowstone hot spring. The American plate is also a major tectonic plate.
3. The Eurasian Plate
The third plate on the list of the major tectonic plate is the Eurasian plate. And as the name implies, some part of the Asian continent and Europe sits in this plate. It also comes as the third-largest plate in terms of size.
This tectonic plate though stands as the third-largest, has diverse eye-opening geographical information. One is the famous Himalayan Range. The collision of two plates formed the Himalayan Mountains. This includes the meeting of the Indian Plate and Eurasian Plate.
Also, this Eurasian plate is an active one. Its territory is likely to witness the occurrence of natural disasters such as earthquakes and volcanoes. The area where the plate occurs also measures 67,800,000sq kilometers.
4. The African Plate
Well, part of the continent of African sits on this plate. This African plate also consists of some regions of the Atlantic and Indian Oceans too. The plate is the fourth-largest in terms of size. It measures 61,300,000 sq kilometers and is a major plate.
Other plates in the world:
It measures 60,900,000 and is the fifth-largest among the tectonic plates. The Antarctic plate is also a major plate.
This plate was created many years ago. And as its name implies, the Indo-Australian plate developed due to the meeting of the Australian and Indian plates. This plate also measures 58,900,000 sq kilometers. Plus, it is a major tectonic plate, too.
South American Plate
The last plate on the list of major tectonic plates is the South American Plate. And for the records, tectonic activity that occurs at the boundary, particular between the Nazca and South American plate, has a hand in the orogeny and volcanic activity the region is experiencing. This plate also measures 43,600,000 sq kilometers.
This plate encompasses Somalia, an African country. It is a minor plate that measures 16,700,000 sq kilometers.
Others are the Nazca plate, Philippine Sea plate, Arabian plate, Caribbean plate, Cocos plate, Caroline plate, and Scotia plate.
Plate Movement: How Does It Take Place?
We have talked about what happens when oceanic and continental plates collide. I also believe you now know the differences between the two plates. Well, let me refresh your memory.
The oceanic plate is thinner and denser than the continental plate. The continental is thicker. Both are also the two types of plates we have on planet earth.
Alright, let’s go back to the plate movement. How does it happen? Here is the simple answer you need to know.
Plates’ movement does occur as a result of one thing. And that is the intense amount of heat that occurs in the Earth’s core that is ball-shaped. It makes molten rock existing in the mantle layer of the earth to move.
The pattern of movement is known as convection cell. It is formed when a warmer material rises, cools down and then sinks. When it sinks, the process starts again. It gets warmed and then rises sky high again.
There was a misconception about how plates appear on top of convection cells. In the past, scientists were thinking they surfed on top of the gigantic convection cells of the mantle. Now they believe the tectonic plates move by themselves. They do not surf along.
New parts that emerge from the plate also rises because they tend to be warmer, and the plate in question is thinner.
On the other hand, the older parts emerging from a plate will likely sink into the mantle, particularly at the subduction zones. The reason is that they tend to be colder and also a bit thicker in size than the mantle material lying underneath, which is warmer. The word used to describe this term is known as “slap pull.”
So, now I presume you know what happens when two oceanic plates collide. As I said, when two oceanic plates collide, the one with lesser density will come under the one with higher density. That is what happens. I also mentioned that the two tectonic plates we have are the continental and oceanic plates. However, the tectonic plates are divided into varied types with regard to their sizes. We have the major, minor, and micro tectonic plates. So that is it about this post. I hope you enjoyed reading it.