Name:____________________                                     Test: Core, Mantle, Crust;

Spheres of the Earth

Studying the Earth

Note:

 

Direct Observation

 

Definition

What do we study with it?

 

 

Direct observation is when you can use your 5 senses, sight, hearing, touch, taste and smell directly to study something.

We can only study what is on or near the first few kilometers of the crust using direct observation.

****Rock samples

 

Indirect Observation

 

Definition

What do we study with it?

 

 

Indirect observation is when you cannot use your 5 senses directly to study something so you must use models or technology to study it.

We study the mantle and the core by indirect observation – using a seismograph and rock samples and models.

 

****Seismic Waves

 

What type of machine do we use to study the core or the mantle?

 

We use a seismograph and study the seismic waves.  There are two types of seismic waves: S-waves stop in liquid and P-waves slow down.

 

What are the three spheres of the Earth?

 

Hydrosphere (all water on Earth), Lithosphere (the hard rock surface of the Earth) 

Atmosphere (all the gases that surround Earth.

"Atmos"- Vapor/Gas

 

What is our lithosphere mostly made of?                                       

 

Our lithosphere is mostly made up of rock, sand, and soil.

The two layers that make up the lithosphere are the crust and upper mantle 

 

What are the three main layers of the Earth?

 

The core, the mantle and the crust.

 

On/in which layer does all life exist?

 

 

 

All life exists on or near the top of the crust.

 

What are the two types of crust?

 

There is oceanic and continental crust.

Oceanic- Sima

Continental - Sial

 

Which type of crust is thinner but denser?

 

The oceanic crust is thinner but denser that is why it is on the bottom!

 

Which type of crust is thicker but lighter?

 

 

The continental crust is thicker but less dense that is why it is on the top!

 

 

What two main elements are in our crust?

 

Our crust is mostly made of the elements silicon and oxygen.

 

What type of rock is oceanic crust mostly made of?

 

Oceanic crust is made up of a heavy dense igneous rock called basalt (to help you remember – salty oceans – basalt!).

 

What type of rock is continental crust mostly made of?

 

Continental crust is made up of the lighter igneous rock – granite.

 

What are the segments of the Earth’s crust that are moving called?

 

 

The segments of pieces that the Earth is broken into are called plates.  These plates are floating on a semi-solid asthenosphere (in the mantle).

 

 

What thin layer separates the crust from the upper mantle?

 

The Mohorovicic Discontinuity is the thin layer between the crust and the upper mantle.

 

What thin layer separates the lower mantle from the outer core?

 

The Gutenberg Discontinuity is the thin layer between the lower mantle and the outer core.

 

What is the property that gives part of the mantle (the asthenosphere) the ability to flow?

 

The property of plasticity allows our asthenosphere to flow – which causes our plates to move.  This is the bottom part of the upper mantle!

 

What is liquid rock that hardens outside the Earth called?

 

Liquid rock that hardens outside of earth is called Lava.  

 

What is liquid rock that hardens inside the Earth called?

 

 

Liquid rock that hardens inside of earth is called Magma.

 

How does the Earth spin on its axis?

 

The Earth wobbles as it spins on its axis!

Crust 3- 40 miles thick-- cool

Thinnest layer

All life exists here

 

Mantle Most mass and volume

1800 miles thick

1600- 4000 degrees Fahrenheit

 

Outer Core Liquid

1400 miles thick

4000-9000 degrees Fahrenheit

 

Inner  Core Solid

800 miles thick

7000-9000 degrees Fahrenheit

 

 

Geology

 

The study of the Earth's composition, structure, processes and history

 

 

 

How do scientists know the “states” of the layers of Earth that we cannot use direct observation for?

 

 

 

 

 

Scientists study the seismic waves that return from the core and the mantle. 

They noticed that p-waves slow down when they reach the areas that we believe are semi-solid or liquid (asthenosphere and the outer core).  

They notice that they stop when they hit the lithosphere, the lower mantle and the inner core, which we believe are solid.