How do we see inside the Earth?

1. How do we see inside the Earth? • What do we use? • __________________________ • Seismology • ____________________________ • What do we know that produces seismic waves?

2. P-waves “P” or Primary waves • _______________ • _______________ • _______________ • Travel through all mediums ( solid, liquid and air)

3. “S” Waves • “S” or Secondary waves • _______________ • Vibrate ____________/ ____________ • _____________ than “P” waves • Only travel through _______________

4. The Crust • ________ __________ • Like an eggshell • ___________ • ___________ • Can crack • Two regions: • ______________ (Basalt rock) • ______________ (granite rock) • Crust is _______ dense than the mantle • Like ice on water; the crust _____________ on the mantle

5. The Mantle • _____________ • Like the crust • __________ • __________ • Iron, magnesium, calcium are heavier elements • Mantle is ________ dense • How does the Earth’s crust add to the density of the mantle? • __________ ___________ down on the mantle…it compresses the minerals, increasing the pressure and squeezing them into rocks.

6. The Mantle • Higher temperature • Why? • __________ __________ • Decay of radioactive elements

7. Layers of The Mantle • Upper mantle • ___________ • Rigid rock upper portion of upper mantle • ___________ • Lies beneath lithosphere and “__________” like plastic • It is ________…silly putty • Lower mantle

8. The Core • ________ layers: inner and outer core • ____ Earth’s volume • ____ Earth’s mass • 2x as dense as the Earth’s mantle • Why? • Made of _____ ______ • Inner core is VERY hot! • Some places as hot as the surface of the sun!

9. The Inner Core • ______ ______ • How? • __________ from Earth keeps Iron packed tightly; doesn’t allow it’s atoms to ______

10. The Outer Core • Outer Core • _______ Iron • _______ pressure • _____ and _____ as Earth rotates • Creates _______ _________ • Affects Earth’s ________ • Produces _______ ______ • Possibly responsible for Earth’s magnetic field

11. Convection Currents • What are convection currents? • ________ of heat flows from ______ to ______ • This sets up a convection current in the ________

12. Effects of Convection Currents • When the current comes at a weaker part of the ________, for example at a _______, ________ comes above the earth's surface. • This is called ______ _______. • The movement of these plates goes very slowly. • The _______ of two tectonic plates causes an _________. • The ________ _______ along the bottom of the _______ causes the moving of the tectonic plates.

13. Continental Drift & Tectonic Plates • __________ Hypothesis on Continental Drift • The World’s continents are in ________ • At one time, the continents were ______ together as one… • This was known as _______ • They fit together like a jigsaw puzzle

14. Continental Drift • Wegner’s theory proposed the landmass known as _______ started breaking up • Separated into two parts: ______ and ________ • Wegner’s theory of the separation of Pangea was supported by ______, _________, _________ and _________ evidence

15. Seafloor Spreading • Seafloor is not _________ • Constantly _________ itself • ____ ________ ______ (longest & tallest mountain range in the world, center of the ________ Ocean) • Forms ________: Iceland and Azore • There are _______ in the mountains

16. Plate tectonics • __________ move because they are _________ in plates • The plates shuffle or move _____ of the Earth’s surface • Plates move in _______ _______ and different ______ from each other • There are ______ large plates and several smaller plates

18. Plate Boundaries • _________ Boundaries • Plates move _____from each other • Comes from rock in the ______________ • Partially melted • The rock partially melts = _______ • It was _____ before it left the _______ of the Earth

19. Convergent boundaries • Plates move _______ each other

20. Transform fault boundaries • Plates ______ ______ each other

22. Earthquakes • Devastating • ______ (force) applied to _____ • Stress causes ______ • Eventually the rock cannot bend anymore • It breaks and releases ______ ______ • The released energy ( ______ _____) travel out in all directions

23. Earthquakes cont • The initiating site of the seismic wave: _______ • The point at Earth’s surface directly above the focus: ________ • Measured on a _______ _______ ( the increments are _____ fold in magnitude…)

24. Tsunami • Seismic sea wave • Created by an __________