Volcano Study Guide Flashcards
A volcano that is erupting, or showing signs it will erupt soon
Active
A currently quiet volcano expected to erupt in the future
Dormant
Volcano never expected to erupt again
Extinct
Hot, melted rock material on Earth’s surface
Lava
Hot, melted rock material beneath Earth’s surface
Magma
Avalanche of hot ash, rock fragments and gas
Pyroclastic flow
Instrument that records earthquakes
Seismograph
Instrument used to measure the slope of a volcano’s side
Tiltmeter
Opening in the Earth’s crust through which magma and gases can escape
Vent
Vent and cone of material built around it by previous eruptions
Volcano
Type of volcano with a broad base and gently sloping sides
Shield
Type of volcano with a small base and steep sides
Cinder cone
Type of volcano with a broad base and steep sides near the top
Composite
Type of eruption that creates a shield volcano
Non-explosive or quiet
Type of eruption that creates cinder cone volcanoes
Explosive or violent
Type of eruption that creates composite volcanoes
Both explosive and non-explosive
Fast moving lava with a rough jagged surface
Aa
Very thick, very slow moving lava creating jumbled heaps with sharp edges
Blocky
Medium speed lava with smooth and rounded wrinkles
Pahoehoe
Underwater lava flow with a lumpy appearance
Pillow lava
Large solid chunk of rock blasted from the volcano
Volcanic block
Blob of magma that hardens in the air
Volcanic bomb
Pebble sized bits of magma which hardened in the air
Lapilli
Teeny tiny bits of rock and minerals, the smallest piece of pyroclastic material
Ash
The cause of most volcanoes
Plate tectonics
