1. Week 2 HSSP Summer 2007

2. What is a volcano?

3. http://interactive2.usgs.gov/learningweb/textonly/teachers/volcanoes.htm

4. Why do volcanoes erupt? http://laurier.vsb.bc.ca/StudentP/RosaViv/Redoubt2.jpg

5. Why volcanoes erupt: Magma has H 2 O and CO 2 gases dissolved in it. These gases form bubbles as the magma rises to the surface and make it erupt Like a opening soda!

6. http://vulcan.wr.usgs.gov/Outreach/Publications/GIP19/

7. May 1980 Mt. St. Helens eruption http://video.google.c om/videoplay?docid =397741638297212 6736&q=Mt.+St.+He lens+1980+eruption +movie&total=17&st art=0&num=10&so= 0&type=search&plin dex=0http://video.google.c om/videoplay?docid =397741638297212 6736&q=Mt.+St.+He lens+1980+eruption +movie&total=17&st art=0&num=10&so= 0&type=search&plin dex=0 http://vulcan.wr.usgs.gov/Volcanoes/MSH/Images/before_after.html

8. May 1980 Mt. St. Helens eruption http://vulcan.wr.usgs.gov/Volcanoes/MSH/Images/before_after.html

9. May 1980 Mt. St. Helens eruption http://vulcan.wr.usgs.gov/Volcanoes/MSH/Images/before_after.html

10. Mt. St. Helens today http://vulcan.wr.usgs.gov/Volcanoes/MSH/Images/before_after.html

11. Mt. St. Helens today http://vulcan.wr.usgs.gov/Volcanoes/MSH/Images/MSH04/movies_and_animations.html

12. What comes out of a volcano?

13. Lava! Lots of different kinds: 1.Ropy lava - Hawaiians call it pahoehoe http://www.nps.gov/archive/havo/images/lava_20050628_janet_lg.jpg

14. What comes out of a volcano? Lava! Lots of different kinds: 1.Ropy lava - Hawaiians call it pahoehoe 2.Sharp lava - Hawaiians call it ‘a’a http://volcanoes.usgs.gov/Imgs/Jpg/Kilauea/30212265-054_large.jpg

15. What comes out of a volcano? Eruptive cloud: gases - water vapor carbon dioxide nitrogen sulfur dioxide ash - tiny bubbles of magma that freeze when they erupt

16. What comes out of a volcano? Pyroclastic Flows = hot gas & ash from plume that quickly become heavier than air http://www.calstatela.edu/faculty/acolvil/volcanos/pinatubo_flow.jpg Yikes!

17. What comes out of a volcano? Lahars = mud flow (pyroclastic flow + water = mud) http://vulcan.wr.usgs.gov/Outreach/AboutVolcanoes/

18. What comes out of a volcano? Volcanic Bombs = lava that cools in the air and becomes aerodynamic (like a football) http://www.indiana.edu/~g103/G103/wk3/bomb.jpg

19. What comes out of a volcano? Lots of different products! http://www.science-art.com/gallery/98/98_182007234045.jpg volcanic bombs pyroclastic flows lahars gas & ash

20. How is magma formed?

22. Melting by heating

23. Decompression melting

24. Melting due to change in the Solidus

25. Why do these two eruptions look different? http://www.windows.ucar.edu/earth/images/shield_volcano_1.gifhttp://www.volcanodiscovery.com/volcano-tours/typo3temp/pics.jpg Stratovolcano: More ash, less lava Cone shape volcano Shield Volcano: More lava, less ash Volcano isn’t cone shaped

26. http://www.windows.ucar.edu/earth/images/shield_volcano_1.gifhttp://www.volcanodiscovery.com/volcano-tours/typo3temp/pics.jpg Because they erupt magma of different: 1) volume 2) viscosity 3) volatile-content (gas) the 3 “V”s

27. What do these mean? 1) volume 2) viscosity 3) volatile-content the 3 “V”s

28. Volume Stratovolcano Shield Volcano

29. What do these mean? 1) volume 2) viscosity 3) volatile-content the 3 “V”s

30. Viscosity: A measure of how much a fluid resists flowing HIGH VISCOSITY Resists Flowing, Thick, Moves Slowly honey LOW VISCOSITY Flows Easily, Thin, Moves Quickly water

31. Magma is a liquid made up of different chemical species: SiO 2, MgO, FeO, Al 2 O 3, CaO, K 2 O etc. The amount of each of these chemical species affects the how easily the magma flows More SiO 2  harder to flow (more viscous)

32. What do these mean? 1) chemical composition 2) viscosity 3) volatile-content the 3 “V”s

33. http://vulcan.wr.usgs.gov/Outreach/Publications/GIP19/

34. Low SiO 2, Low viscosity, Low volatile-content  SMALL ERUPTION  Shield Volcanoes - example Hawaii

35. High SiO 2, High viscosity, High volatile-content  BIG EXPLOSIVE ERUPTION!  Stratovolcanoes - example Mt. St. Helens

36. Stratovolcanoes vs. Sheild Volcanoes http://dsc.discovery.com/convergence/p ompeii/interactive/interactive.htmlhttp://dsc.discovery.com/convergence/p ompeii/interactive/interactive.html

37. There are volcanoes underwater At Mid-ocean ridges

38. And there are volcanoes on other planets http://www.aerospaceweb.org/question/astronomy/solar-system/solar-system.jpg

39. Volcanoes in our solar systemMars http://www.lukew.com/marsgeo/img/volcanic_image2_bg.jpg Insert movie: http://veimages.gsfc.nasa. gov/13676/VolcanoCompar e_640x480.mpg http://www.astro.virginia.edu/class/skrutskie/images/mars_volcano_size_comp.jpg http://volcano.und.edu/vwdocs/planet_volcano/mars/Shields/ol ymp.jpg

40. http://www.visitandlearn.co.uk/factfiles06/images/volcanoes-14.jpg http://volcano.und.edu/vwdocs/planet_volcano/venus/Ven_Ref_all.gif Venus The Moon Most volcanic planet – over One Thousand volcanoes!! Over 1600 large shield volcanoes!!

41. Io is the most volcanic body in the solar system Can be completely resurfaces in 1 million years!! Doesn’t have craters http://apod.nasa.gov/apod/image/0212/iovolcano_gal_big.gif Io – moon of Jupiter

42. Can you think of some famous volcanoes? http://www.mapsofworld.com/major-volcanoes.htm

43. Group Exercise Each group is given an information packet about a famous planet Your goal is to fill the “Volcano Profile” sheet In the end, each group will tell the class about their volcano

44. Volcanoes around the world http://www.mapsofworld.com/major-volcanoes.htm

45. Next week Learn to identify the rocks in your backyard!

46. Homework: Bring in a rock Any rock you like It can be from anywhere –Your backyard –A trip you went on –Someone gave it to you

47. Andesite vs. Basalt Andesite - –from stratocone volcanoes (explosive) –more silica –more viscous (resists flow) –pinkish or reddish in color Basalt - –from shield volcanoes (not explosive) –less silica –less viscous –blackish in color