The Solid Earth Layers and Structure (Intro to Geology)

More than meets the eye…

What is the Earth like?

Earth like an Apple…

Travel from the Outside In…

The Crust- the SKIN Crust- made of mostly O and Si (and others such as Al, Fe, Ca, Na, K and Mg) Crust- made of mostly O and Si (and others such as Al, Fe, Ca, Na, K and Mg) Oceanic- under the ocean Thinner than continental. Continental- part of the land, under your feet

Mantle- the FLESH Mantle- 1,800 miles thick, Divided into two (2) parts, made of rock Mantle- 1,800 miles thick, Divided into two (2) parts, made of rock Upper Mantle Lower Mantle LA

Upper Mantle Divided into (2) two parts- think L.A. Divided into (2) two parts- think L.A. Asthenosphere- plastic like, semi- solid, flows like silly putty, caramel Lithosphere- rigid (hard, stiff) Note: includes the crust (can break!!!)

Lower Mantle Semi Solid Semi Solid What does it mean? What does it mean? Compared to taffy, caramel or rubber! Compared to taffy, caramel or rubber!

Outer Core Liquid metal Liquid metal Ocean of Spinning metal! Ocean of Spinning metal! Made up of Fe and Ni Made up of Fe and Ni VERY Hot!!!!!! Hotter than the Inner Core! VERY Hot!!!!!! Hotter than the Inner Core! WHY? WHY?

Inner Core- the PIT Solid metal Solid metal Spinning metal! Spinning metal! Mostly iron (Fe) Mostly iron (Fe) Also nickel (Ni) Also nickel (Ni) Very hot!!!!!! BUT- cooler than the Outer Core! WHY? Very hot!!!!!! BUT- cooler than the Outer Core! WHY? Together with the Outer Core it generates the Earth’s magnetic field! Together with the Outer Core it generates the Earth’s magnetic field!

What does it all look like?

The Layers… Lower Mantle Upper Mantle Oceanic Crust under ocean Continental Crust

Do you Know it? This does not include the core!!!

You got it?

What is the Moho? Mohorovicic Discontinuity Mohorovicic Discontinuity What is it? What is it?

Apples or avocados??? What do you like?

One last look...

Do you know it?

Plate Tectonics Continental Drift and Pangaea

Continental Drift Observations Observations Moving land Moving land Hypothesis that says the continents have once been joined together in one big land mass: Hypothesis that says the continents have once been joined together in one big land mass: Pangaea Pangaea

Pangaea

How? What does it look like?

Under the sea… Mid-Atlantic Ridge Mid-Atlantic Ridge Mid-ocean Ridges Mid-ocean Ridges

Evidence? Seafloor spreading Seafloor spreading Moving seafloor Moving seafloor New rock from the inner earth New rock from the inner earth

Plate tectonics The theory of plate tectonics describes how and why the continents move. The theory of plate tectonics describes how and why the continents move. Plate= rigid slab/piece of rock Plate= rigid slab/piece of rock Tektonikos= greek word meaning “construction” or “to build” Tektonikos= greek word meaning “construction” or “to build”

Can you make Pangaea?

Plate Tectonics 2 Plate Movement

REMINDER: Plate Tectonics The theory of plate tectonics describes how and why the continents move. Think Pangaea!!!! The theory of plate tectonics describes how and why the continents move. Think Pangaea!!!! Plate= rigid slab/piece of rock Plate= rigid slab/piece of rock Tektonikos= greek word meaning “construction” or “to build” Tektonikos= greek word meaning “construction” or “to build”

How does this look like? The Earth’s crust is broken into large pieces called plates. Imagine a cracked, hard-boiled egg. The Earth’s crust is broken into large pieces called plates. Imagine a cracked, hard-boiled egg.

Plate Boundaries The Edges of the plates, where they touch other plates, are called plate boundaries The Edges of the plates, where they touch other plates, are called plate boundaries

Plate Movement vs. Boundary The way the plates move, determines the type of plate boundary… meaning… The way the plates move, determines the type of plate boundary… meaning… ConvergentDivergentTransform Towards Each otherAway from each other Slip sideways past each other

Plate Movement These plates move in three different ways These plates move in three different ways A. Towards eachother B. Away from eachother C. Slip sideways past eachother

What does it look like?

Once again…

Divergent Boundary Plates pulling away from one another Plates pulling away from one another What do we get? Ocean Ridges (under water) or Rift Valleys (on land) What do we get? Ocean Ridges (under water) or Rift Valleys (on land)

Transform Boundary Plates slide and grind next to each other, side to side Plates slide and grind next to each other, side to side What do we get? Faults, earthquakes. San Francisco What do we get? Faults, earthquakes. San Francisco

Convergent Boundary Plates push against each other Plates push against each other How many kinds? How many kinds? O+O, C+O and C+C O+O, C+O and C+C What do we get? What do we get?

What happens? Why? The movement of these plates over millions of years have caused the continents to drift (move). Think Pangea. The movement of these plates over millions of years have caused the continents to drift (move). Think Pangea. The oceans and continents sit on top of these plates and therefore they move when the plates move. The oceans and continents sit on top of these plates and therefore they move when the plates move. Why? Convection currents within the Earth Layers. Think pot of boiling water! Why? Convection currents within the Earth Layers. Think pot of boiling water!

Seismic Movement Earthquakes

Earthquake Notes Please answer the following questions. Please answer the following questions. Yes, please write questions- it will help you when you come back to study from your notes! Yes, please write questions- it will help you when you come back to study from your notes!

Questions to answer p What is the definition of an earthquake? 2. What is the Elastic Rebound Theory? 3. What is an epicenter? Focus? Magnitude? 4. What causes most earthquakes? Where? 5. At what kind of boundaries? 6. Where are earthquakes most likely to occur around the world? 7. What is the Pacific Ring of Fire? 8. What is a fault zone? 9. What instrument do we use to measure earthquakes? 10. What does this instrument measure? 11. How many kinds of waves are there? 12. What makes them different? What are they? 13. How do we locate an earthquake? 14. What is the scale we use to measure earthquakes? 15. What does the scale measure?

What are Earthquakes? Where? Vibrations of the Earth’s crust Vibrations of the Earth’s crust Where? Where? They occur mostly when rocks under stress suddenly shift or move along a fault They occur mostly when rocks under stress suddenly shift or move along a fault What is a locked fault? What is a locked fault?

Elastic Rebound Theory

Words to know… Seismic Waves- energy in the form of vibrations as the rocks move Seismic Waves- energy in the form of vibrations as the rocks move Aftershocks- smaller tremors, as the rocks come back into their original position Aftershocks- smaller tremors, as the rocks come back into their original position Focus- where rocks first slip Focus- where rocks first slip Epicenter- point on the earth’s surface directly above the focus Epicenter- point on the earth’s surface directly above the focus Magnitude- how strong Magnitude- how strong

What’s it look like?

The Pacific Ring of Fire

What? What? Where? Where? What? What? Fault Zones Fault Zones Volcanoes Volcanoes Trenches Trenches

How do we measure… just kidding!

How do we measure? Seismograph Seismograph Detects and records seismic waves in three different ways (guess?) Detects and records seismic waves in three different ways (guess?) What kind of waves? What kind of waves?

Seismic Waves P waves- primary waves- fastest, travel through solid and liquid P waves- primary waves- fastest, travel through solid and liquid S waves- secondary waves, travel through solid only S waves- secondary waves, travel through solid only Surface Waves- when P and S waves reach the surface, they become surface waves, slowest Surface Waves- when P and S waves reach the surface, they become surface waves, slowest Think water ripple effect… Think water ripple effect…

Waves…

Locating an Earthquake Three Stations needed Three Stations needed Why? Why? How? How?

How do we measure an Earthquake? Magnitude (Richter Scale)- measures energy released, related to cause. 1 and up Magnitude (Richter Scale)- measures energy released, related to cause. 1 and up Intensity (Mercalli Scale)- measures amount of demage it causes, related to effect. I to XII and description Intensity (Mercalli Scale)- measures amount of demage it causes, related to effect. I to XII and description

Last notes… Tsunamis- giant wave caused by an earthquake whose epicenter is on or under the ocean floor. Tsunamis- giant wave caused by an earthquake whose epicenter is on or under the ocean floor. Aftershocks Aftershocks Predictions Predictions Pg. 111….think video we saw. Pg. 111….think video we saw.