Name:
Date: Per:
Ch. 6 Volcano Notes
Volcanoes are weak spot in the ______where ______comes to the surface
- Magma is molten ______, ______, and ______from the mantle
- Magma becomes ______when it comes to the surface
- Lava cools to become ______
Types of Rock
- ______- molten material, such as lava or magma, cools and hardens
· Slow cooling- ______crystals (granite)
· Fast cooling- ______crystals (basalt)
- Metamorphic- great ______and ______changes minerals or rock
· Heat and pressure ______inside the earth
- ______- sediment ______and ______together
· Sediment- small pieces of ______or ______that have been broken down by erosion or weathering
The Rock Cycle
- Slowly ______, ______, and ______rock
- ______and many pathways
Volcanoes and Plate Tectonics
- Volcanic belts are found at plate ______, such as the ______around the Pacific Plate
- ______boundaries- magma comes out of ______to build mountains
- ______boundaries
· ______plate sinks
· Rock on top melts and becomes ______
· Magma ______and becomes ______
Hot Spots are ______that form when magma erupts through ______to get to the surface
- Examples: Hawaii and Yellowstone National Park
Parts of a Volcano
- ______-collects magma
- ______- tube that connects magma chamber to ______
- ______- opening on the Earth’s crust
- ______- area covered by lava
- ______- bowl shaped are around a volcano’s ______vent
- ______- large circular depression formed when magma chamber empties and roof collapses
Eruptions
- ______and ______force magma out of a volcano
- ______makes magma thick and sticky
- Types of eruptions
· ______eruptions- lava oozes to surface
§ thin, runny lava that is low in ______
§ Hawaiian Islands
§ examples are pahoehoe and aa
· ______eruptions- thick and sticky lava which traps ______
§ water makes eruptions more ______
§ produces ______material
· magma that erupts as fragments of molten material ______in the air
· pieces of ______that break off
§ Mt. St. Helens in 1980
Life Cycle
- Geologists determine how likely a volcano will ______again
- Stages
· ______- erupting or will erupt in the near future
§ Mt. Shasta and Lassen Peak
- ______- “Sleeping,” but can become ______again
§ Long Valley in Eastern Sierras
- ______- unlikely to ______again
· Diamond Head in Honolulu
Volcanic Landforms
- Made of______, ______, and other materials
- Types of volcanoes
· Shield volcano- made from ______eruptions
§ Low in ______
§ ______with ______slopes
· ______- made form explosive eruptions
§ High in ______
§ Steep, cone-shaped, found in ______
· ______- alternating layers of ______material and lava flow
§ also known as ______
§ most common
- Lava plateaus- lava flows out of long cracks called ______
· thin, runny lava flows far before cooling
Magma Landforms
- Formed when ______goes into ______, but does not come to the surface
- Magma cools ______
- ______exposes harden magma
- Types
· ______Necks- magma hardens in ______
· Dikes and sills- magma cools ______rock layers
§ igneous intrusions
§ ______are horizontal
§ dikes ______rock layers
· ______- massive rock forms when large bodies of magma cools