Grade 10 SCIENCE | Quarter 1 Module 5 (PART 2) | CONVERGENT BOUNDARY

Summary

This educational presentation delves into the dynamics of convergent plate boundaries, exploring three primary types: oceanic-oceanic, oceanic-continental, and continental-continental convergence. It illustrates how each type results in distinct geological features like volcanic island arcs, trenches, and mountain ranges, using examples such as the Indonesian Archipelago, the Andes, and the Himalayas. The script also clarifies terminological differences and emphasizes the inevitability of earthquakes in such regions due to plate movements.

Takeaways

• 🌋 Oceanic-oceanic convergence results in the formation of volcanic island arcs, such as the Indonesian Archipelago, Philippine Island Arc, and Japanese Island Arc.
• 📍 Converging oceanic plates, like the Australian Plate and Sunda Plate, create volcanic islands like the Indonesian Archipelago.
• 🌊 The Philippine Island Arc is formed from the convergence of the Philippine Sea Plate and the Sunda Plate.
• 🇯🇵 The Japanese Island Arc results from the convergence of the Pacific Plate and the Eurasian Plate.
• ⛰️ Oceanic-continental convergence creates continental volcanic arcs and trenches, with the Rocky Mountains being a prime example.
• 🗻 The Andes Mountains in South America formed from the convergence of the Nazca Plate and the South American Plate.
• 🏔️ Continental-continental convergence, like that of the Indian Plate and Eurasian Plate, results in mountain ranges such as the Himalayas.
• 🔄 No subduction occurs during continental-continental convergence, leading to mountain formation instead of volcanic activity.
• 💥 All types of convergent plate boundaries (oceanic-oceanic, oceanic-continental, continental-continental) can cause earthquakes due to the movement of plates.
• 🔄 The video provides a comprehensive recap of the different types of convergent boundaries, their outcomes, and specific examples of each.

Q & A

What is an oceanic convergence?

Oceanic convergence is a type of plate tectonic boundary where two oceanic plates move towards each other, resulting in the formation of volcanic island arcs and trenches due to subduction of the denser plate beneath the other.

What are the examples of volcanic island arcs mentioned in the script?

The Indonesian Archipelago, the Philippine Island Arc, and the Japanese Island Arc are examples of volcanic island arcs formed due to oceanic convergence.

How does the Indonesian Archipelago form as a result of plate tectonics?

The Indonesian Archipelago is formed by the convergence of the Australian Plate and the Sunda Plate, both of which are oceanic plates, leading to the subduction and formation of volcanic island arcs.

What is the difference between an oceanic plate and a continental plate?

An oceanic plate is denser and typically thinner than a continental plate. Oceanic plates are usually found under the oceans, while continental plates carry the continents and are less dense, making them typically thicker.

What is the role of the Philippine Plate in the formation of the Philippine Island Arc?

The Philippine Plate, a minor plate, converges with the Sunda Plate, leading to the subduction of the denser plate and the formation of the Philippine Island Arc.

What is the process called when one tectonic plate moves under another?

The process is called subduction, where the denser plate sinks beneath the less dense plate, often leading to volcanic activity and the formation of trenches.

What is the difference between a volcanic island arc and a continental volcanic arc?

A volcanic island arc is formed at oceanic-oceanic convergent boundaries, while a continental volcanic arc is formed at oceanic-continental convergent boundaries. However, in the script, both are referred to as volcanic island arcs for simplicity.

What are some examples of continental volcanic arcs mentioned in the script?

The Rocky Mountains, the Cascades, the Sierra Nevadas, and the Andes Mountains are examples of continental volcanic arcs formed due to oceanic-continental convergence.

How do mountain ranges form at continental-continental convergent boundaries?

At continental-continental convergent boundaries, the lack of subduction due to both plates being less dense leads to the collision of the plates, resulting in the formation of mountain ranges through the buildup of rock and sediment.

What is the Himalayas an example of?

The Himalayas is an example of a mountain range formed by continental-continental convergence, specifically the collision of the Indian Plate with the Eurasian Plate.

Why do earthquakes occur at convergent plate boundaries?

Earthquakes occur at convergent plate boundaries due to the movement and interaction of tectonic plates, such as sliding past each other, colliding, or subducting, which releases energy in the form of seismic waves.

Outlines

00:00

🌊 Oceanic Convergence and Island Arcs

This paragraph introduces the concept of oceanic convergence, focusing on the formation of volcanic island arcs. It highlights examples such as the Indonesian Archipelago, the Philippine Island Arc, and the Japanese Island Arc, which are results of the convergence between oceanic plates like the Australian Plate, Sunda Plate, and the Pacific Plate. The explanation includes the process of subduction, where denser oceanic plates are drawn beneath lighter continental plates, leading to the creation of trenches and volcanic arcs. The paragraph also clarifies the distinction between volcanic island arcs and continental volcanic arcs, setting the stage for further discussion on different types of convergent boundaries.

05:03

🌋 Oceanic Continental Convergence and Volcanic Features

The second paragraph delves into oceanic continental convergence, a process where oceanic plates converge with continental plates, resulting in the formation of continental volcanic arcs. It emphasizes the similarity between volcanic island arcs and continental volcanic arcs, both being chains of volcanoes formed due to subduction. The paragraph provides examples such as the Rocky Mountains, Cascades, and Sierra Nevadas in North America, and the Andes in South America, which are outcomes of the convergence of various plates including the North American Plate, Pacific Plate, and the Nazca Plate. The discussion also touches on the transformation of these volcanic arcs into mountain ranges over time due to tectonic movements and the decrease in magma supply.

10:06

🏞️ Continental Continental Convergence and Mountain Building

This paragraph discusses the third type of convergent boundary, continental continental convergence, where two continental plates collide due to their lower density compared to oceanic plates, preventing subduction. The result of this collision is the formation of mountain ranges and frequent earthquakes. The paragraph uses a simulation to illustrate the process, showing how two continental crusts come together to form a series of mountains over millions of years. The Himalayas are presented as a prime example of this process, formed by the convergence of the Indian Plate and the Eurasian Plate, and include the world's highest peak, Mount Everest. The paragraph concludes with a brief history of the Indian subcontinent's movement towards Asia, leading to the creation of the Himalayas.

15:08

📚 Recap of Convergent Boundaries and Their Outcomes

The final paragraph provides a recap of the entire discussion on convergent boundaries, summarizing the three types: oceanic-oceanic, oceanic-continental, and continental-continental convergence. It outlines the geological outcomes of each type, such as volcanic island arcs and trenches for oceanic-oceanic convergence, continental volcanic arcs and trenches for oceanic-continental convergence, and mountain ranges for continental-continental convergence. The paragraph also mentions that any movement along these boundaries can cause earthquakes. The video concludes by inviting viewers to ask questions in the comment section and expressing hope that the content has been helpful in understanding the module on plate tectonics.

Keywords

💡Oceanic Convergence

Oceanic convergence refers to the tectonic process where two oceanic plates move towards each other. In the video, this concept is central to understanding the formation of volcanic island arcs. For instance, the Indonesian Archipelago is a product of the convergence of the Australian and Sunda plates, both of which are oceanic.

💡Volcanic Island Arc

A volcanic island arc is a chain of islands formed by volcanic activity at the boundaries of oceanic plates. The video discusses the Philippine Island Arc and the Japanese Island Arc as examples of such features, which are created by the subduction of one oceanic plate beneath another, leading to volcanic activity.

💡Subduction

Subduction is the process where one tectonic plate moves under another and sinks into the mantle due to its higher density. The video script explains that in oceanic convergence, the denser oceanic plate subducts beneath another plate, leading to the formation of trenches and volcanic arcs.

💡Trench

A trench is a long, narrow depression in the Earth's crust, typically found at the boundary between two tectonic plates where one is being subducted beneath the other. The video uses trenches as an example of the geologic features that form as a result of oceanic convergence.

💡Continental Volcanic Arc

Continental volcanic arcs are chains of volcanoes that form when an oceanic plate converges with a continental plate. The video script distinguishes this from volcanic island arcs, noting that continental volcanic arcs are part of oceanic-continental convergence, such as the Rockies in North America.

💡Convergent Boundary

A convergent boundary is a type of plate boundary where two plates move towards each other. The video script outlines three types of convergent boundaries: oceanic-oceanic, oceanic-continental, and continental-continental, each resulting in different geologic features.

💡Mountain Range

A mountain range is a series of mountains that form a continuous chain. The video script discusses the formation of mountain ranges as a result of continental-continental convergence, where two continental plates collide and push up the Earth's crust, exemplified by the Himalayas.

💡Himalayas

The Himalayas is a mountain range in Asia, which includes Mount Everest, the highest peak in the world. The video script describes the Himalayas as an example of a mountain range formed by the continental-continental convergence of the Indian Plate and the Eurasian Plate.

💡Plate Tectonics

Plate tectonics is the theory that describes the movement of the Earth's lithosphere, which is divided into several plates. The video script uses plate tectonics to explain the processes of convergence and the resulting geologic features such as arcs and mountain ranges.

💡Earthquake

An earthquake is the shaking of the Earth's surface caused by the sudden release of energy in the Earth's crust. The video script mentions that earthquakes are a common result of all types of convergent boundaries due to the movement of tectonic plates.

💡Andes Mountains

The Andes is a continuous range of highlands stretching along the western edge of South America. The video script cites the Andes as an example of a continental volcanic arc formed by the convergence of the Nazca Plate and the South American Plate.

Highlights

The Indonesian Archipelago, Philippine Island Arc, and Japanese Island Arc are examples of products of oceanic-oceanic convergence.

Oceanic plates can be part of either continental or oceanic lithospheres, as seen in the convergence of the Australian and Sunda plates.

Volcanic island arcs are formed by the subduction of one oceanic plate beneath another, leading to volcanic activity.

The Philippine Island Arc is a result of the convergence between the Philippine Plate and the Sunda Plate.

The Japanese Island Arc is formed by the convergence of the Pacific Plate and part of the Eurasian Plate.

Oceanic-continental convergence involves subduction of an oceanic plate beneath a continental plate, resulting in continental volcanic arcs.

The term 'continental volcanic arc' is used interchangeably with 'volcanic island arc' in the module, despite being a different geological feature.

The Rockies, Cascades, and Sierra Nevadas are examples of continental volcanic arcs formed by oceanic-continental convergence.

The Andes Mountains in South America are also a product of oceanic-continental convergence between the Nazca Plate and the South American Plate.

Continental-continental convergence occurs when two continental plates collide, leading to the formation of mountain ranges.

The Himalayas, including Mount Everest, are an example of a mountain range formed by continental-continental convergence.

The movement of tectonic plates over millions of years is responsible for the formation of these geological features.

Earthquakes are a common result of all types of convergent boundaries due to the movement of plates.

A simulation demonstrates the process of subduction and formation of volcanic arcs in oceanic-continental convergence.

The distinction between volcanic island arcs and continental volcanic arcs is clarified to avoid confusion.

A recap of the three types of convergent boundaries and their outcomes is provided for better understanding.

The presentation concludes with an invitation for questions and a summary of the key points discussed.

Transcripts

back to our original

presentation we are now about to discuss

what are the examples of

products of oceanic oceanic convergence

okay so examples of island orcs are

examples of volcanic island arcs

are these first we have the indonesian

archipelago

second we have the philippine island arc

or the philippines

itself and we have the japan

or the japanese island arc

okay so as you can see in this picture

we have

drawn uh red lines

across the map which shows the different

island arcs and other island arcs that

you can see

on the map okay

so the indonesian archipelago is a

product of

the convergence of the australian plate

and the sunda plate which are both

oceanic plates so remember that a plate

can be both

continental or oceanic

so it can be a combination

so this parts of the australian plate

which is oceanic and the soon the plate

which

is the part of the eurasian plate

the lower part of the eurasian plate

which is

also oceanic they converge to form the

indonesian

archipelago at the same time for the

philippine island arc or the philippines

it is a product of the convergence

between the philippine plate so we know

that we have the

philippine c plate it is a minor plate

and the sunda plate as well

which is here the philippine plate and

the

sunda plate and then finally

um the japan or the japanese island arc

is a product of the convergence

of the pacific plate

and the part of

eurasian plate

so let's move now to the next type of

convergent

boundaries the next type is oceanic

continental convergence

still here in this type of convergent

boundary we still have

subduction and obviously the denser

oceanic plate would

undergo the process also the

geologic process or feature that you can

have in this type of convergence are

almost the same with the previous

type which we have discussed a while ago

oh here we still have a trench we still

have an earthquake

but then we will now have a continental

volcanic ark

however again as what i have stressed a

while ago

the continental volcanic ark is called

volcanic island arc

in your module so don't be confused

about it

i'm using another term here to

distinguish it

from the island arc so

there we also have this um image

from your module so how ign

is the type of crust that

or type of lithospheres that are

involved

in the convergence

of apareas so again at the point where

the two lithospheres meet would become a

trench

and then you have this subducting

denser oceanic lithosphere and after

some time it would melt and become

a volcanic ark

so the volcanic arc is still a set of

volcanoes not a single

volcano but a group of volcanoes and so

i have here

a more complex picture of continental

oceanic convergence by the way you can

call it

oceanic continental or continental

oceanic

so it's not really an issue

and so let's move on with the simulation

again

so we will be placing the crust here

by the way it doesn't matter if you

choose old or young here

as long as it's oceanic crust and we

have the continental crust

and both show labels show seawater

automatically it's always the oceanic

crust that would

go under the continental crust

it can't be possible that the

continental crust would go

under the oceanic crust because again

oceanic crust is denser than

continental grass the denser lithosphere

would undergo

subduction don't forget that

again automatic mode put io and then

time elapse

in millions of years let's see what

happens

again this process of going down

beneath the other crust is called

subduction

so after some time it would melt and

would form the

arcs here

that's 14 billion years

again this is not possible overnight

it would take millions of years

and it stopped at 50 million years

so

it's very similar to oceanic oceanic

convergence so here we have a trench

and then we have the continental

volcanic

arcs

so again now before we proceed with the

last part

or the last type of convergence i would

like to reiterate

that in this particular presentation

i indicated the terms volcanic island

arc

or island arc for oceanic oceanic

convergence

and continental volcanic arcs

for oceanic continental

convergence however in your module on

this

two since they are similar to each other

they are

both called volcanic island arcs

so problem

because um they are

similar to each other they are chains of

volcanoes

okay so let's move now to the different

examples of this

volcanic arks or continental volcanic

arks

so first we have the rockies or the

rocky mountains which is found

in north america the rocky mountains or

the rockies

is a product of the convergence of the

north american plate and the one de fuka

or the pacific plate

indeed that the rocky mountains is

somehow situated

here kasemaju matagal nadawyan

they might be volcanoes in the past but

then they became

inactive because there is a less and

less

source of magma below them because of

movement of the earth and so on and so

forth

so these mountains were once volcanoes

but then due to passing of time they

just became mountains

next we also have the cascades and shera

nevadas

so these are near the rockies

still in the north american plate so the

cascades

is um the product of the convergence of

one defuca plate

and north america while the shera

nevadas which is

found below the cascades is the

product of the convergence of the

pacific plate and the north american

plate

we also have the andes mountains so the

andes mountains can be found in the

south americas this

is a product of the convergence of the

nazca plate

and the south american

plate

um we have mentioned one de fuka and we

mentioned pacific plate so wonderful

kind pacific plate

are oceanic plates they converge with

the continental plate which

is north america and in this case we

also have

nazca plate which is a an oceanic plate

which converged with the south american

plate which is

continental thus making them examples

of oceanic continental

convergence

finally we will go to the last part of

this discussion which is all about the

continental continental convergence

as the title implies continental

continental convergence

is the convergence between two

continental

plates now because the two plates that

are moving towards each other are both

continental

which are less dense compared to

an oceanic plate therefore no subduction

happens

they will just collide and form

something

in between what are the geologic

processes that

occur we have mountain ranges

and earthquakes

so as you can see we have here the

picture as illustrated

in your module

let's go back to the simulation

we place two continental crusts

and then we will be observing what

happens

again there's no subduction here

only collision

okay so the timer stopped at 35 million

years

ago which are

the volcanic island arcs and

also um again there is no subduction

and not only one mountain is formed

we have a series or a

group of mountains or mountain ranges

so as for the best example of a

continental continental convergence

we have the himalayas

so the himalayas was formed from the

convergence of the indian plate

to the eurasian plate

so the himalayas include the

very well known mount everest which is

the tallest mountain

or the highest mountain on earth

and apparently according to scientists

um years ago or millions of years ago

india and asia

were not together

india is a part of asia but then

according to

scientists india was here

so nahiwala is india 71 million years

ago

and then because of the movements of

these plates

it slowly moved towards the eurasian

plate

until okay until

the himalayas was formed

because india is continental

eurasia part of the eurasia majority of

it is also

continental so before we end this

discussion let's have a short recap of

what we have discussed today

first we have uh discuss what a

convergent boundary is

a convergent plate boundary is a plate

boundary where

two plates are moving towards each other

and then

we also have three types of convergent

plate boundaries

first the oceanic oceanic second the

oceanic continental

and third the continental continental

convergence

or convergent boundary now as for the

difference among the three

so an oceanic oceanic convergence

would produce a volcanic island arc and

a trench

an oceanic continental convergence could

produce

a continental volcanic arc and a trench

and finally for a continental

continental convergence

a mountain range would be formed

so for all of these types of convergence

or convergent plate boundaries

any type of movement would cause an

earthquake so we also have discussed

the examples of the outcomes of these

different types of convergence

or you can just rewind this video if you

have forgotten about them

and so that's all for today

if you have questions i can

simply write them on the comment box

below

and i hope that this video was able to

help you

understand more the contents of module

number five

so that's all for today till our next

discussion

[Music]

bye