INTERNAL STRUCTURE OF THE EARTH | Unit 1 Module 2 - Grade 10 Science Lesson | MELC-Based [TEACH]
Summary
TLDRWelcome to CaViTeach, where today's lesson delves into Earth's internal structure, highlighting its five layers: the crust, mantle, outer core, inner core, and atmosphere. The inner core, made of iron and nickel alloy, is incredibly dense and hot at 5000°C, contrasting with the molten outer core at 2000°C. The mantle, composed of silicate rocks and divided into the upper, transition, and lower regions, is solid despite its extreme heat. The crust, Earth's thin outer layer, varies in thickness and composition, with continental crust being less dense than oceanic. This episode wraps up with a teaser for the next, focusing on the atmosphere.
Takeaways
- 🌐 The Earth has five concentric layers: crust, mantle (upper and lower), outer core, inner core, and atmosphere.
- 🔥 The inner core is the hottest part of the Earth with a temperature of about 5000°C, composed of solid iron and nickel alloy.
- 🌀 The outer core, with a temperature of around 2000°C, is made up of molten iron and nickel alloy, contributing to Earth's magnetic field.
- 🌍 The mantle, which makes up 80% of Earth's volume and 68% of its mass, is primarily composed of silicate rocks containing silicon, iron, oxygen, and magnesium.
- 🌡️ The asthenosphere, a layer within the mantle, is a soft and weak layer responsible for the movement of lithospheric plates, leading to earthquakes.
- 🏔️ The crust is the thinnest and outermost layer, divided into oceanic crust (7-10 km thick) and continental crust (35-40 km thick), with different compositions and densities.
- 🌋 The Mohorovicic Discontinuity marks the boundary between the crust and the mantle, while the Gutenberg Discontinuity is the boundary between the outer core and the lower mantle.
- 🧲 The Earth's magnetic field is believed to be generated by the movement of molten iron and nickel in the outer core.
- 🌌 The Lehmann Discontinuity is the boundary between the solid inner core and the molten outer core, discovered by Inge Lehmann.
- 🌬️ The atmosphere, the fifth layer, will be discussed in a future episode, highlighting the structure and composition of Earth's outermost layer.
Q & A
What are the five concentric layers of the Earth?
-The five concentric layers of the Earth are the crust, the mantle (divided into upper and lower portions), the outer core, the inner core, and the atmosphere.
What is the diameter of the Earth's inner core?
-The inner core has a diameter of approximately 2,600 kilometers.
What are the main constituents of the inner core?
-The inner core is primarily composed of an iron and nickel alloy.
What is the approximate temperature of the inner core?
-The inner core has an approximate temperature of 5,000 degrees Celsius.
Why is the inner core solid despite its high temperature?
-The inner core is solid due to extreme pressure, a phenomenon known as pressure freezing, which counteracts the melting effect of the high temperature.
How do scientists know that the inner and outer core are composed of iron and nickel alloy?
-Scientists deduce this composition from the Earth's magnetic field, which is generated by the movement of molten iron and nickel in the outer core, and from the density of the Earth, which is higher than that of crust rocks, suggesting denser materials like iron and nickel in the core.
What is the significance of the Lehmann Discontinuity?
-The Lehmann Discontinuity is the boundary between the inner and outer core, named after Inge Lehmann who discovered that the outer core is molten and the inner core is solid.
What is the mantle's composition and its role in the Earth's structure?
-The mantle is composed mostly of silicate rocks containing silicon, iron, oxygen, and magnesium. It makes up 80% of Earth's volume and 68% of its mass, serving as an intermediate zone between the crust and the core.
What is the Asthenosphere and its relation to plate tectonics?
-The Asthenosphere is a soft, weak, and partially molten layer of the upper mantle that causes the movement of lithospheric plates, leading to continental drift and earthquakes.
What are the two types of crust found on Earth and their main differences?
-There are two types of crust: continental crust, which is thicker and composed of less dense rocks like granite, and oceanic crust, which is thinner and made up of denser rocks like basalt.
What is the Mohorovicic Discontinuity and who is it named after?
-The Mohorovicic Discontinuity is the boundary between the crust and the mantle, named after the Croatian meteorologist and seismologist Andrija Mohorovicic.
Outlines
🌐 Exploring Earth's Internal Structure
This paragraph introduces the Caviteñan Virtual Teaching (CaViTeach) and delves into the Earth's internal structure, highlighting its five concentric layers: the crust, mantle, outer core, inner core, and atmosphere. It starts with the innermost layer, the inner core, which is approximately 2,600 kilometers in diameter and composed of iron and nickel alloy. The inner core's temperature is around 5,000 degrees Celsius, which is significantly hotter than the outer core at 2,000 degrees Celsius. The paragraph discusses the composition of both the inner and outer core, explaining that while the inner core is solid due to 'pressure freezing,' the outer core is molten. The discussion also touches on how scientists deduced the composition of the cores, mentioning the Earth's magnetic field and the density of the planet compared to meteorites. The boundaries between the inner and outer core (Lehmann Discontinuity) and the mantle (Gutenberg Discontinuity) are introduced, with a brief mention of the mantle's composition and its division into the upper mantle, transition zone, and lower mantle.
🌍 Delving into the Mantle and Crust
The second paragraph continues the exploration of Earth's layers, focusing on the mantle and crust. It describes the mantle as the intermediate zone between the crust and the core, composed mainly of silicate rocks rich in silicon, iron, oxygen, and magnesium. The mantle is divided into the upper mantle, transition zone, and lower mantle, with the Asthenosphere, a soft, weak layer made of hot molten materials, playing a crucial role in plate tectonics and earthquake activity. The boundary between the outer core and lower mantle, known as the Gutenberg Discontinuity, is named after Beno Gutenberg. The paragraph then transitions to the crust, detailing its composition and the difference between oceanic and continental crust. It explains that the crust is thinner than the mantle, with the continental crust being less dense and composed of granite, while the oceanic crust is denser and made of basalt. The Mohorovicic Discontinuity, marking the boundary between the crust and mantle, is also introduced. The paragraph concludes with an invitation for questions and a call to action for viewers to engage with the content by liking, sharing, and subscribing to the channel.
Mindmap
Keywords
💡Crust
💡Mantle
💡Outer Core
💡Inner Core
💡Lehmann Discontinuity
💡Asthenosphere
💡Gutenberg Discontinuity
💡Mohorovicic Discontinuity
💡Concentric Layers
💡Pressure Freezing
Highlights
Introduction to the five concentric layers of the Earth: crust, mantle, outer core, inner core, and atmosphere.
The inner core is approximately 2,600 kilometers in diameter and consists of iron and nickel alloy.
The inner core has an extreme temperature of 5,000 degrees Celsius, which is 250% hotter than the outer core.
The outer core is molten iron and nickel alloy despite being cooler than the inner core, due to pressure freezing.
Earth's magnetic field is generated by the movement of molten iron and nickel in the outer core.
The overall density of the Earth suggests a denser core composition than the crust's rocks.
Meteorite analysis reveals the Earth's core likely contains iron and nickel, similar to Chrondite.
The Lehmann Discontinuity marks the boundary between the solid inner core and the molten outer core.
The mantle is the largest layer of Earth, making up 80% of its volume and 68% of its mass.
The mantle is composed mainly of silicate rocks with a temperature range from 1,500 to 3,000 degrees Celsius.
The asthenosphere, a part of the upper mantle, is responsible for the movement of lithospheric plates and continental drift.
The Gutenberg Discontinuity is the boundary between the outer core and the lower mantle.
The crust is the thinnest and outermost layer, consisting of oceanic and continental types with different compositions and thicknesses.
The Mohorovicic Discontinuity is the boundary between the crust and the mantle.
The crust's composition varies, with continental crust made of less dense rocks like granite and oceanic crust of denser rocks like basalt.
A detailed table of the element composition of the Earth's crust is provided.
A teaser for the next episode, which will discuss the Earth's atmosphere as the fifth concentric layer.
Invitation for students to ask questions and engage with the content through likes and shares.
Transcripts
hello students! Welcome to Caviteñan Virtual Teaching or CaViTeach
for today's episode we will be discussing the internal structure of the Earth
for we all know there are five concentric layers of the earth
the first one is the crust the second one is the mantle which is divided
to upper at lower portions. Third is the outer core. Fourth is the inner core
and the fifth one, can you guess it?
You are right! It is our Atmosphere!
let us discuss these concentric layers one by one starting with the innermost
the inner core has two thousand six hundred kilometers in diameter and
consists of iron and nickel alloy. The inner core of our planet
has an approximate temperature of five thousand degree celsius
this is 250 percent hotter than the next layer which is the outer core
which has an approximate temperature of two thousand degrees celsius
and has a thickness of two thousand two hundred fifty kilometers
if we will look into the approximate temperatures of the innermost layers of our planet,
which one is hotter?
the outer core with two thousand degree celsius or the inner core with five thousand degree celsius?
if you think the inner core is hotter, you are right!
both inner and outer core are composed of Iron and Nickel Alloy
So if inner core is the hottest,
Which of them has molten iron and nickel alloy?
the inner core? or the outer core?
if you answered inner core...
well i cannot blame you
but the correct answer is outer core
the inner core is made up of solid iron and nickel alloy
while the outer core is made up of molten iron and nickel alloy
Why?
the extreme temperature of the inner core could have molten the iron
and Nickel but it is believed to be solidified as a
result of extreme pressure scientifically known as pressure freezing
but, how did our scientists were able to say
that the inner at outer core are made up of iron and nickel alloy? (How did you says so?)
How did you say so?
here are the explanations of the scientists regarding that
First, the earth has magnetic field
and they believe that we have magnetic field because of the movement
of molten iron and nickel in the outer core.
Iron and Nickel are both dense and magnetic in nature
Second, the overall density of the earth is way higher than the density of rocks in the crust
this suggests that the inside must be made up of something denser than rocks
based on the analysis of experts on meteorites
they found out that it contains Chrondite
Chrondite is made up of the elements like Iron
Silicon, Magnesium, Oxygen, and some contains Nickel
the earth and meteorites has almost the same densities
thus the earth's mantle rock and the meteorites minus
its iron have the same densities does it make sense
doesn't make sense
the boudary between inner and outer core is called Lehmann Discontinuity
It is named after Inge Lehmenn who is a Danish Seismologist
who discovered that the the outer core is molten and the inner core is solid
the second concentric layer that we will discuss is the mantle
the mantle is the intermediate zone between the crust and the core and
consists mostly of solid rocks
the mantle makes up the 80 percent of Earth's volume and 68 percent of Earth's mass
it has an approximate thickness of two thousand nine hundred kilometers
with a temperature ranging from fifteen thousand degrees celsius to thirty thousand degree celsius
it is 150 to 300 times as hot as boiling water
the mantle is mainly made up of silicate rocks specifically the elements
silicon, iron, oxygen and magnesium
and contrary to common belief, the mantle is solid since both s waves and p waves can pass through it
the mantle has three parts or regions. The upper mantle, the transition zone, and the lower mantle
the upper mantle has a thickness of 670 kilometers
and the lower mantle has a thickness of 2230 kilometers
In the mantle, we can find the layer called the Asthenosphere
or the low-velocity zone
it is a soft, weak, top layer of the upper mantle that is made up of hot molten materials
it has a thickness of 180 kilometers and has a temperature ranging from 300 degree celsius
to 800 degrees celsius
since the asthenosphere is molten and flowing underneath the crust
it causes the movements of lithospheric plates
which is responsible to the movement of continents
that is why we have earthquakes
the boundary between the outer core and lower mantel is called
Gutenberg Discontinuity named after Beno Gutenberg who is an American-German Seismologist
the boundary between upper mantle and crust, which we will discuss next
is called Mohorovicic Discontinuity
named after Andrija Mohorovicic who is a Croatian Meteorologist and Seismologist
the next concentric layer that we will discuss is the Crust
the crust is the thinnest, outermost, rocky layer of the earth
that is made up of two parts
the oceanic crust and the continental crust
continental crust has a thickness of 35 to 40 kilometers
and is mainly made up of the elements sodium
oxygen, silicon, aluminum, potassium, and calcium
the continental crust is usually found under land masses
and is made up of less dense rocks such as granite
On the other hand, the oceanic crust has a thickness of 7 to 10 kilometers
Oceanic Crust is found under ocean floors and is made up of dense rocks such as basalt.
The crust has two layers, the upper layer which is composed of granite
which is only found in the continental crust
and the next layer is made up of Basalt
which is found in oceanic crust and continental crust
if we are going to compare the mass of oceanic crust and continental crust, oceanic crust is the heaviest.
here is a table that shows the element composition of our crust
we will end here our discussion on the concentric layers of the earth
on our next episode we will discuss the fifth concentric layer
which is the atmosphere
so if you have questions on the concentric layers that we discussed earlier,
just leave a message below
have you learned something in our teach vlog episode?
if there's nay, give this video a thumbs up
and share this video to your classmates so that they will also learn about this topic
and do not forget to subscribe and hit the notification bell so that you will be updated in my next teach vlogs
Ver Más Videos Relacionados
Layers of the Earth | Structure of the Earth | Educational Science Lesson
Layers of the Earth 🌎 | Crust, Mantle, Outer Core, Inner Core | Educational Science Lesson & Quiz
Structure Of The Earth | The Dr. Binocs Show | Educational Videos For Kids
Layers of the Earth for Kids | Learn facts about the different layers of Earth
Day-10 || BA 1st semester Geography Unit-1 ( Core ) by Mukul Sir #ba1styear #geography
Inside The Layers Of The Earth | iKen | iKen Edu | iKen App
5.0 / 5 (0 votes)