DO NOWDO NOW

Identify plates B, D, G, I, J, L, and N

Layers of the EarthLayers of the Earth

The diagram to the right shows two ways to classify Earth's layers. One way, shown on the left, is based on composition (what the layers are made of). The other way, shown on the right, is based on physical properties of the layers (solid vs. liquid, rigid vs. soft, etc.). These may also be called zones. In most cases, the boundaries between the physical layers do not line up with the boundaries of the compositional layers.

The CrustThe Crust

The crust is the outermost, thinnest, least dense layer. Continental crust is made mostly of the rock granite and is thicker and less dense than oceanic crust. Oceanic crust is made mostly of the rock basalt. Overall, crustal rocks are rich in the elements silicon (Si) and oxygen (O).

The oceans still have crust under it, it just thinner than the continental crust.

What is the lithosphere?What is the lithosphere?Lithosphere = crust + rigid mantle

What are tectonic plates?What are tectonic plates?Earth’s lithosphere is separated into pieces that

fit tightly together like a puzzle.

Tectonic plates are the large slabs of lithosphere that move around on the asthenosphere

Tectonic plates can…Tectonic plates can…Move around (they float on top of the

asthenosphere)Have either…

◦Land + water◦Water

Convection CurrentConvection Current

Hot material from deep inside Earth rises and cooler material sinks

This motion occurs in the asthenosphere

What allows tectonic plates to move?

Convection Currents Convection Currents and Plate Motionand Plate Motion

There are 7 large tectonic plates, and about 14 smaller There are 7 large tectonic plates, and about 14 smaller ones. ones.

What is plate tectonic theory (PTT)?What is plate tectonic theory (PTT)?

Plate Tectonic Theory combines the theories of continental drift and seafloor spreading.

This theory states that all of Earth can be divided into sections called tectonic plates, and that these have the ability to move.

Over time, these tectonic plates, with the help of seafloor spreading, have caused Pangaea to form today’s 7 continents.

Learning Objective: We will learn how plate tectonic

theory helps explain continental drift and seafloor spreading.

What is a plate boundary?What is a plate boundary?The boundary or dividing line between 2

tectonic plates.

Learning Objective: We will learn how plate tectonic

theory helps explain continental drift and seafloor spreading.

What are the types of plate What are the types of plate boundaries?boundaries?

Transform: 2 plates SLIDE past each otherConvergent: 2 plates move TOWARDS each

otherDivergent: 2 plates move AWAY from each

other

Learning Objective: We will learn how plate tectonic

theory helps explain continental drift and seafloor spreading.

Plate BoundariesPlate Boundaries

Learning Objective: We will learn how plate tectonic

theory helps explain continental drift and seafloor spreading.

Transform plate boundary

Convergent plate boundary

Snack TectonicsSnack Tectonics

RULES1. Do NOT eat the materials until instructed

to do so2. STAY in your seat at all times3. RAISE your hand if you need something4. WAIT for instructions before doing

ANYTHING5. FILL out your worksheet as we go6. Failure to follow ALL rules will result in

detention and loss of snacks

FOR TUESDAYFOR TUESDAY

Read Chapter 17, Section 4 and Chapter 22, Section 3

Missing assignments are due ThursdayExtra Credit Projects are due Thursday