1. Unit 6 Earthquakes and Volcanoes

2. Warm Up Friday Analyze this bar graph- this graph compares deaths from EARTHQUAKES per time period

3. How are Richter Scales and Mercalli Intensity Scale connected?
Both measure earthquakes
How are they not connected?
Richter Scales measure magnitude and Mercalli Scales measure observable damage.

4. Moving rocks get caught on each other at faults.
Moving rocks create STRESS points
The breaking point is reached
Energy is released

5. Earthquakes 1. What are earthquakes?
Earthquakes are movement of earth’s crust caused by plates shifting and releasing stored energy
Rocks on either side of a fault snag and build up pressure
When the rocks break ... shake, rattle and roll!

6. Earthquakes 2. What are seismic waves?
2. Seismic waves are shock waves in the earth caused by an earthquake.

7. Earthquakes 3. What are P waves? ( push and pull forces)
3. P waves are primary waves. They are fast and longitudinal
( push and pull forces)
P waves are the to 'arrive' at a seismic station. The P wave can move through solid rock and fluids, like water or the liquid layers of the earth. It pushes and pulls the rock it moves through just like sound waves push and pull the air.

8. Earthquakes 4. What are S waves? S waves move rock
4. S waves are secondary
or shear waves. They are
slower. S waves are
transverse- move from
side to side.
S waves move rock
particles up and down,
or side-to-side—
perpendicular to the
Direction of the wave.

9. Earthquakes 5. What are L waves?
5. L waves are “love waves”
Named after a British scientist who calculated a mathematical model for a wave.
L Waves are the fastest waves and move from ground to side to side. In other words, they are P or S waves that hit the surface.

11. Earthquakes where rocks first break and move.
6. What is the focus of an earthquake?
6. The focus is
where rocks first
break and move.
7. What is the epicenter?
7. The Epicenter is the point on earth’s surface directly above the focus.

13. Earthquakes
8. What is a seismograph?
8. A seismograph is an instrument used to record seismic waves.

14. Earthquake Scales 9. What is the Richter Scale?
9. A Richter Scale measures the total energy released by an earthquake
b) +1 means x32

15. #29 Quick Quiz- Video Clips Write answers in complete sentences
1. What is one of the first signs of a tsunami?
2 : List two safety measures that Japan has implemented to reduce the damage of tsunamis.

17. Earthquake Scales 10. What is the Mercalli Intensity Scale?
10. The Mercalli Intensity Scale is a scale that measures the intensity of an earthquake. The scale quantifies the effects of an earthquake on the Earth's surface, humans, objects of nature, and man-made structures on a scale of I through XII, with I denoting a weak earthquake and XII one that causes almost complete destruction.

20. http://videos. howstuffworks

21. Locating Earthquakes

22. http://videos. howstuffworks

23. Earthquake Zones 11. Where are the 3 major earthquake zones? 11.
Ring of Fire- is located around the edge of the Pacific Ocean.
Mid-Atlantic Ridge- this zone is caused by sea floor spreading
The Mediterranean –Asiatic Belt- occurs because continental plates are colliding.

27. Earthquake Evidence 12. Describe ground level earthquake evidence
12. Ground level earthquake evidence is side to side or up and down shifts of the ground. The earth has moved mostly slow and steady and is called creep

28. Earthquake Evidence 13. Describe landscape evidence of earthquakes.
13. There are 5 descriptions:
Slide – rapid down slope movement of soil, debris, & rock
Scarp – cliff made by uplifted or subsided earth

29. http://videos. howstuffworks

30. Earthquake Evidence 13. Fissures – long cracks in soil or rock
Tsunami – an ocean wave caused by earthquakes
a) can be 30m high at the shore
Buildings on loose soil have more damage.

31. Quick Quiz- Video Clips: Answer in complete sentences
1. What is the first sign of a tsunami?
2 : What are two safety precautions that Japan has implemented to help reduce the threat of tsunamis?

32. http://videos. howstuffworks

33. Volcanoes 1. What is a volcano?
1. A volcano is any opening in the earth’s crust that release molten rock.

35. Volcanoes 2. What is a vent?
2. An opening through which material reaches the surface
3. What is a crater?
3. A crater is a hollowed out area in the top of a volcano

36. Volcanoes 4. The pipe is a long crack through which magma moves
4. What is the pipe?
4. The pipe is a long crack through which magma moves
5. What is the magma chamber?
5. A chamber with a pocket of magma.

37. Volcanoes
Label the parts

38. Volcano Video Part I

39. Volcanoes 6. An active volcano has erupted during the last century.
6. What is an active volcano?
6. An active volcano has erupted during the last century.
7. What is a dormant volcano?
7. A dormant volcano has not erupted for hundreds of years, but it believed that it has the ability to erupt.

40. Volcanoes
8. What is an extinct volcano?
8. A volcano is considered extinct if it has not erupted for thousands of years.

41. Volcanoes 9. List the sequence of events when a volcano erupts?
9. Lava flows out –usually gently and quietly
2) Then an explosion of debris occurs. The following are products of a volcano
pyroclasts – fragments of broken rock from a volcano
ash – hot fine-grained material
bombs – large molten or semimolten chunks

42. Volcanoes 10. What are cinder cone volcanoes?
10. A cinder cone formed from
ash and cinders in explosive
eruptions. Cinder cones
volcanoes are smaller, coned
shaped, and steep slopes.
Example:
Paricutín, Mexico

43. http://videos. howstuffworks

44. Volcanoes 11. What are shield volcanoes?
11. Shield volcanoes are from
from lava flow eruptions. They
have broad with gentle slopes.
An example is
Muana Loa, Hawaii

45. http://videos. howstuffworks

46. Volcanoes They are explosive and have lava eruptions
12. What are composite volcanoes?
12. Composite volcanoes are formed from
alternating layers of lava and pyroclasts.
Characteristics include:
They are explosive and have lava eruptions
They are large with steep slopes
Examples:
Mt. Fuji, Japan & Mt. St.
Helens, Washington

47. Site was not discovered until 1748
13. Case study: Pompeii
13.
79 CE
Site was not discovered until 1748
Provided archeologists extraordinary details about daily life in Roman Empire
Some believe that volcano took 2 months to completely bury the town as people were “found” wearing winter clothing in the summer, dates of minted coins and letters
Populist tourist site in S. Italy

48. Erupted 05/18/1980. Caused by an earthquake on 03/20/1980.
13.
14. Case study: Mt. St. Helen
14.
Erupted 05/18/1980. Caused by an earthquake on 03/20/1980.
Most deadliest and costly volcano in US history.
“Glacier mountain”
Due to the eruption, at the top of the mountain is a 1 mile long horseshoe crater.
Volcano “steamed” until January 2008

49. Pompeii:
Mt. St. Helens:

50. Igneous Rock Features
Why study? Many features formed underground by igneous activity are at the earth’s surface by erosion.

51. Igneous Rock Features 15. List intrusive igneous rock formations
15. Batholiths, sills, dikes, and volcanic necks.

52. Igneous Rock Features 16. What are batholiths?
16. Large intrusive igneous rock body that forms when magma being forced upward toward Earth’s crust cools slowly and solidifies underground.

53. Igneous Rock Features
17 . What is a dike?
17.Magma that is forced into a crack that cuts across layers and hardens.
18. What is a volcanic neck?
18. Solid igneous core of a volcano left behind after the softer cone has been eroded.

54. Igneous Rock Features
19. What is a caldera?
19. Large, circular-shaped opening formed when the top of a volcano collapses. Crater Lake is an example