1 / 45

Volcanoes

Volcanoes . Types, lava, and rocks. Cinder Cone. Simplest type Built from volcanic debris from a single vent Most have bowl shaped crater Height reaches about 1000 ft above their surroundings. Parícutin in 1994. Mexico Formed over 9 years. Composite or Stratovolcano. Steep sided

langer
Télécharger la présentation

Volcanoes

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. Volcanoes Types, lava, and rocks

  2. Cinder Cone • Simplest type • Built from volcanic debris from a single vent • Most have bowl shaped crater • Height reaches about 1000 ft above their surroundings

  3. Parícutin in 1994 • Mexico • Formed over 9 years

  4. Composite or Stratovolcano • Steep sided • Symmetrical cone • Alternating layers of ash, lava, cinder blocks • Can be over 8000 ft tall • Have crater with central vent

  5. Famous composite volcanos • Mount Fuji in Japan • Mount Cotopaxi in Ecuador • Mount Shasta in California • Mount Hood in Oregon • Mount St. Helens and Mount Rainier in Washington.

  6. Shield Volcano • Entirely built of lava • Gently sloping sides • Looks like warrior's shield from the side

  7. Mauna Loa

  8. Lava Dome • Formed by lava that is too thick to flow any large distance • Lava piles around the vent

  9. Kelud Volcano

  10. Types of lava • AA • Slow moving • Sharp edges • Pahoehoe • Fast moving • Smooth edges • Pillow • Form under water • If on land is evidence that was once under water

  11. AA lava

  12. AA lava

  13. Pahoehoe

  14. Pahoehoe

  15. Pillow Lava

  16. Pillow Lava

  17. Rocks that form from volcanos

  18. Igneous rocks • Rocks that form from lava • Can cool either quickly or slowly • The way they cool will impact their structure • 2 types – intrusive and extrusive

  19. Granite • Best know of all igneous rocks • Mixture of different types of rocks • Formed underground

  20. Granite

  21. Rhyolite • Extrusive rock, formed on the surface • Light colored silicates like granite • Cool rapidly

  22. Rhyolite

  23. Andesite • Medium-grey color • Fine grain size • From volcanos

  24. Andesite

  25. Diorite • Intrusive rock, forms underground • Coarse-grained • No visible quartz crystals • Dark color

  26. Diorite

  27. Basalt • Dark colored • Small crystals • Usually formed above ground from volcanic origins • A lot of deposits in Oregon and Washington

  28. Basalt

  29. Gabbro • Forms underground • Dark green to black color • Makes up a lot of oceanic crust

  30. Gabbro

  31. Obsidian • Volcanic glass • Cools very quickly • Black or green in color • Can have very sharp edges when broken • Used as tools for centuries because of sharpness and hardness

  32. obsidian

  33. Pumice • glassy texture • Formed with large amount of gas makes frothy mixture • Many pieces will float in water • Many people use it to smooth out and remove dead layer of skin

  34. Pumice

  35. Scoria • Heavier than pumice • Made of frothy lava with less air • Usually red in color • Used in gas grills to help with distribution of heat

  36. Scoria

More Related