2. Volcanoes A Lesson Plan Written By Tom Huettl

4. Lecture Outline »Areas of Volcanism »Types of Volcanoes »Types of Lava »Viscosity

5. Lecture Outline »Areas of Volcanism »Types of Volcanoes »Types of Lava »Viscosity

6. Areas of Volcanism Sub-ducting Boundaries Plate Sub-ducts below surface into mantle Oceanic-Oceanic Volcanoes form near boundary Mid Ocean Ridges Eruptions occur where plates are diverging

7. Cont.-Cont/ Subducting Graphic taken from : http://147.205.15.81/geology/work/VFT-so-far/orogeny/pl.tect.htmlhttp://147.205.15.81/geology/work/VFT-so-far/orogeny/pl.tect.html

8. Oceanic-Oceanic/Suducting Graphic taken from: http://147.205.15.81/geology/work/VFT-so -far/orogeny/pl.tect.html

9. Mid Ocean Ridges

10. Areas of Volcanism –Hot Spots Hot Spots remain stationary while plates move above

11. Hot Spots Graphic taken from: http://volcano.und.nodak.edu/vwdocs/vw/lessons/atg.htm l

12. Types of Volcanoes –Shield Cone Has a low rounded profile Gentle slopes of 2-10 degrees –Composite Volcano (Strato Volcano) Both pyroclastic layers and lava flows Steep sided near summit with decreasing slope

13. Types of Volcanoes Cinder Cone –Pyroclastic Material (Fragmented material that has been explosively ejected) –Ash and debris accumulates around the vent –Small steep sided cones –

14. Shield Cone

15. Composite Cone/Stratovolcano

16. Cinder Cone

17. Types of Lava Mafic »Silica Poor (45-52%) Intermediate »Silica Composition (53-65%) Felsic »Contains more than 65% Silica

18. –High Viscosity »Slow Flow »High Silica Content » –Low Viscosity »Fast Flow »Low Silica Content » UMD

21. For More Information Visit One of The Following Links The Web's Premiere Source For Volcanoes U.S. Geological Survey, Volcano Hazards Program

22. Electronic Resources http://147.205.15.81/geology/work/VFT-so-far/orogeny/pl.tect.html http://volocano.und.nodak.edu/vwdocs/vwlessons/atg.html http://www.studyworksonline.com/cda/content/worksheet/0,1036,EXP 950_NAV2-77_SWK953,00.htmlhttp://www.studyworksonline.com/cda/content/worksheet/0,1036,EXP 950_NAV2-77_SWK953,00.html http://observe.ivv.nasa/earth/tectonics/Tectonics.html http://members.aol.com/waponi/sound.htm http://www.bftr.com/Pages/projects/dante.html http://volcanoes.usgs.gov/