Volcanoes Flashcards
What determines a volcanic eruption?
molten rock, rock fragments, and hot gases
What happens when magma is high in silica?
gases get trapped, causing a violent eruption
What are rock fragments that are dust like?
volcanic ash
What are rock fragments that are like pebbles?
volcanic cinders
What are rock fragments that are streamlined shaped and still molten when they are thrown out?
volcanic bombs
What are rock fragments that could be as big as a house?
volcanic blocks
What are the main gases in volcanoes?
water vapor and carbon dioxide
What is a dense cloud of super hot gases and rock fragments that race downhill?
pyroclastic flow
Where are volcanoes found?
Convergent boundaries, divergent boundaries, hot spots, Ring of Fire
Where are about 80% of the active volcanoes located?
Ring of Fire
What is a large crater formed by the collapse of a volcano when magma rapidly erupts from underneath it?
caldera
What is a vent through which gases escape and some lava comes out?
fissure
What type of volcano is flat and low in silica?
shield volcano
What type of volcano is steep and gases throw chunks of lava out?
cinder cone volcano
What type of volcano is steep, high in silica, and is the most dangerous type?
composite volcano
