Unit 6 Earthquakes and Volcanoes

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

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.

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

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! http://videos.howstuffworks.com/hsw/5934-geology-earthquakes-video.htm

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

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.

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. http://aspire.cosmic-ray.org/labs/seismic/index.htm

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.

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.

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

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

#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.

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.

http://videos. howstuffworks http://videos.howstuffworks.com/hsw/11899-earthquakes-protecting-structures-from-damage-video.htm

Locating Earthquakes

http://videos. howstuffworks http://videos.howstuffworks.com/hsw/9241-cleopatras-palace-alexandria-video.htm

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.

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

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

http://videos. howstuffworks http://videos.howstuffworks.com/hsw/9214-discovering-plate-tectonics-changing-earths-surface-video.htm

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.

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?

http://videos. howstuffworks http://videos.howstuffworks.com/hsw/25886-tsunami-the-destructive-force-of-tsunami-waves-video.htm http://videos.howstuffworks.com/hsw/25893-raging-planet-history-of-deadly-tsunamis-in-japan-video.htm http://videos.howstuffworks.com/hsw/25895-raging-planet-japan-responds-to-tsunami-threats-video.htm

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

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

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.

Volcanoes Label the parts

Volcano Video Part I http://videos.howstuffworks.com/hsw/19172-understanding-volcanoes-part-one-video.htm

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. http://www.geocodezip.com/v2_activeVolcanos.asp

Volcanoes 8. What is an extinct volcano? 8. A volcano is considered extinct if it has not erupted for thousands of years. http://hvo.wr.usgs.gov/volcanoes/maunakea/

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 http://videos.howstuffworks.com/hsw/6185-mountains-of-fire-an-eruption-video.htm

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

http://videos. howstuffworks http://videos.howstuffworks.com/hsw/9221-when-earth-erupts-cinder-cone-volcanoes-video.htm

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

http://videos. howstuffworks http://videos.howstuffworks.com/hsw/9219-when-earth-erupts-shield-volcanoes-video.htm

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

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

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

Pompeii: http://videos.howstuffworks.com/discovery/28991-assignment-discovery-pompeiis-destruction-video.htm Mt. St. Helens: http://videos.howstuffworks.com/discovery/7161-mt-saint-helens-powerful-erruption-video.htm

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

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

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.

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.

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