Repeated eruptions of lava
How are volcanoes created?
Along plate boundaries
Where most volcanoes form
What do you expect to see during a nonexplosive eruption?
Where molten rock gathers deep underground
Low silica content
Lava that is very runny has...
Type of eruption that occurs when water content is high
How lava flows
Flows like dripping wax
Forms jumbled heaps of sharp chunks
Gets its name from a word that means "little stones"
Can reach the upper atmosphere and circle the Earth for years
Forms when magma explodes into the air and hardens
Shield, Composite, Cinder cone
Main types of volcanoes
Created when the roof of a magma chamber collapses
Temperature increases and pressure decreases
Rock begins to melt
Where tectonic plates collide
Where most active volcanoes form
Where volcanoes form far from tectonic plate boundaries
Measures changes in a volcano's slope
Cinder Cone Volcano
Small volcano; usually erupts only for a short time
Created by a combination of explosive and nonexplosive eruptions
Large, flat area covered by lava
Funnel shaped pit