1. Earthquakes and volcanoes

2. Ex. San Andreas Fault in California
EARTHQUAKES
happen along fault lines which are on transform boundaries but can happen on divergent and convergent boundaries as well
shake the Earth
Ex. San Andreas Fault in California

3. Focus – exact point INSIDE the Earth where earthquake originated
Epicenter – point on Earth’s SURFACE directly above the focus

4. 3 TYPES OF EARTHQUAKE WAVES
Primary/Push Waves (P waves)
longitudinal
move fast in all directions
not much damage (because they are so quick moving)

5. 2. Secondary/Shear Waves (S waves)
transverse
move slower than P waves & in all directions
more damage than P waves

6. 3. Surface/Love Waves (L waves)
make Earth shake and vibrate
most destructive because they are slow and rolling waves
collapses buildings

8. One thing to note:
S waves cannot travel through solids so they will never go through Earth’s core, only the liquid mantle.
P waves can travel through both solids and liquids.

9. Earthquake Terms
Seismology – the study of earthquakes
Seismographs – instrument used to record earthquake waves
Richter Scale – scale used to measure earthquake strength/intensity

10. VOLCANOES
They are openings in the Earth’s crust through which magma escapes
These openings are called VENTS
Formed by subduction (one plate goes under another), rifting (plates pull apart) & hotspots (spot in middle of plate)

11. 3 Types of Volcanoes 1. Shield Volcano -flat, not steep
-lava flows great distances b/c it is runny
-eruptions are mild
-Ex. Hawaiian Islands

12. 2. Composite (Strata) Volcano
-made of layer of ash, cinder, lava
-puffy clouds of ash
-trapped gases cause explosions that go thousands of meters in the air
-Ex. Mt. Fuji, Japan

13. 3. Cinder Cone Volcano
-smaller, most abundant
-trapped gases throw ash particles everywhere which forms the “cone”
-Ex. Paricutin, Mexico

14. Volcanoes occur at divergent and convergent boundaries
Pacific Ring
of Fire 

15. Volcanoes that occur under water are called SEAMOUNTS