1 / 14

Volcanoes

Volcanoes. Chapter 8 Section 2 Pgs. 219 - 224. How volcanoes form. Fissure – crack in the crust, where a conduit forms which acts like a pipe magma travels through Magma is forced upward toward Earth’s surface by denser surrounding rock

reece-lucas
Download Presentation

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 Chapter 8 Section 2 Pgs. 219 - 224

  2. How volcanoes form • Fissure – crack in the crust, where a conduit forms which acts like a pipe magma travels through • Magma is forced upward toward Earth’s surface by denser surrounding rock • Causes an eruption where magma, solids, and gas are spewed out to form cone-shaped mountains

  3. Lava – magma flowing on Earth’s surface through a vent or opening • Craters – circular hole of volcano • Tephra – bits of rock or solidified lava dropping from the air • Reservoir – where magma is stored • Summit – highest point • Vent - opening where lava flows

  4. Where Plates Collide • Volcanoes form by a collision of large plates of crust and upper mantle • Oceanic plate sinks under another plate, rocks melt, forms chambers of magma

  5. Volcanic Risk Maps • Used to prepare people and visitors about unsafe areas

  6. Volcanic Eruptions • Violent or quiet • Lava high in silica produces explosive eruptions • Lava high in iron and magnesium produces more fluid eruptions • The amount of water vapor and gases impact eruptions

  7. Shield Volcanoes • Largest type of volcano • Gently sloping volcano that emits mostly basaltic lava (very fluid) that is long-lasting, gentle eruptions, explosions minimal

  8. Mauna Loa, HI • Made from 5 shield cones • Largest volcano on Earth – Mauna Loa in Hawaii, 6 miles tall

  9. Cinder Cone Volcanoes • Smallest volcano, very steep with large craters • Formed by moderate to explosive eruptions of tephra

  10. Cinder Cone Volcano • Pu ‘ u ka Pele – Hawaii • Mostly found on the sides of shield volcanoes

  11. Composite Volcano • Steep sides • Formed by alternating layers of violent eruptions of tephra and quieter eruptions of lava

  12. Composite Volcano • Most active volcano – Mt. St. Helens in the western part of the state of Washington

  13. Extreme Volcanoes • Largest volcano in the Solar System – Olympus Mons on Mars, 17 miles tall and over 320 miles across.

  14. Questions • Hawaii is an example of what type of volcano? • What are the three types of material that a volcano can emit? • The eruption of Mount Vesuvius buried what town in 79 A.D.? • How did people die in the aftermath of the famous Mount Vesuvius eruption? • Mount St. Helen’s erupted violently in 1980. On what continent is this volcano found?

More Related