Types
The Hawaiian Islands are made from this type of volcano
Shield
Where is the relationship of Earth's volcanoes and plate boundaries
They are mostly found near plate boundaries
When magma has a high silica content it is more likely to create what type of explosion
violent
Common gases that escape through the vents of volcanoes (need 2)
CO2, water vapor, sulfur, and nitrogen
A large depression in a volcano is a
Caldera
When shield volcanoes grow from the ocean floor they form what
Islands
after the rest of a volcano has worn away leaving a pipe made of rock what is this called (Devil's Tower is an example)
volcanic neck
What decreases as lava temperature increases
viscosity
Where does most intraplate volcanic activity occur
Hotspots
Why did people settle near volcanoes?
Fertile soil
What type of volcano usually forms from a single eruption
Chains of volcanoes on the ocean floor
Volcanic island arcs
What partially melts to form magma
solid rock in the crust and upper mantle
Why does magma rise and melt at divergent plate boundaries
Decreased pressure
Participles that are produced during eruptions; they can range in size from fine dust to pieces that weigh serval tons
Pyroclastic materials
What type of volcano has the most explosive eruption
composite (stratovolcano)
Chains of volcanoes on the continental crust
continental volcanic arcs
Does an increase in water content increase or decrease the rock's melting point
Decrease
Magma flows from a magma chamber to the surface through what
pipe or conduit
How does Aa lava look as it cools
Sharp, shiny projections
A fairly symmetrical volcano that has both layers of lava and pyroclastic deposits
composite
When magma is forced between sedimentary layers and creates a flat layer what forms
Sill
Hotter, faster-moving lava
Pahoehoe
Mudflows associated with volcanic eruptions
Lahar
Body of intrusive igneous rocks that has a surface exposure of more than 100 sq Km
Batholith