1. Volcanoes
Chapter 8 Section 2
Pgs

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 On what continent is this volcano found?