Volcanoes Section 1&2🌋 Flashcards
Magma is a molten mixture of
Rock gas and water vapor
Volcanoes for in belts what is the largest called?
Ring of fire
The divergent boundary is where
Crust pulls apart and new crust is added
Convergen plate boundaries is where…
Ocean crust and returns to the mantle
Subduction causes ocean crust to sink in trenches back into the mantle where it melts and rises back as…
Volcanoes
Oceanic/continental forms
Volcanic mountain ranges
Magma reaches the surface and erupts…
Through the crust
Melts through crust like
Blow torch
Can form a chain of volcanic mountains or islands as the plate moves over
The hot spot
What are physical properties?
Detectable without changing the composition of a substance
What is a chemical property
Property that produces a change in the composition
High viscosity=
Slower flowing
Viscosity depends on
Silica content and tempature
70% of magma is
Silica
More silica=
Higher viscosity
Higher viscosity=
Light colored sticky
High colored sticky=
Rhyolite
Dark colored flows easily=
Basalt
Tempature of magma
750°-1175°C
Volcanic glass fibers and globs of volcanic glass is called
Peles hairs and tears
Where does magma form
Athenosphere
Where does magma collect under high pressure
Magma chamber
What happens to the presure as the magma nears the surface
It decreases
What is Lahar
,ud,ash,and tons of debris flowing doenstream
