A land or underwater feature that forms when magma reaches the surface of Earth.
What is a volcano?
100
Fragment of rock or lava dropped from the air during an explosive volcanic eruption ranges in size from volcanic ash to huge boulders.
What is tephra?
100
Magma/lava that contains a low percentage of silica and has low viscosity.
What is basaltic magma and lava?
100
A volcano that is mainly composed of alternating layers of lava and tephra.
What is a composite volcano?
100
A rounded volcanic feature that forms when a mass of highly viscous lava slowly erupts from the vent.
What is a lava dome?
200
The circular or oval-shaped opening of a volcano.
What is the vent?
200
Fine-grained tephra or dust from a volcanic eruption; consisting of tiny, sharp mineral and glass-like particles.
What is volcanic ash?
200
Magma/lava that contains a high percentage of silica and has high viscosity.
What is granitic magma/lava?
200
A huge, gently sloping volcanic landform that is mainly composed of basaltic lava.
What is a shield volcano?
200
What forms as swiftly moving magma flows from a magma chamber, and it's outer surface cools and hardens.
What is a lava tube?
300
A rapidly flowing mixture of volcanic debris and water.
What is a lahar?
300
The result of an unusually hot area in Earth's interior that forms volcanoes when melted rock is forced upward and breaks through the crust.
What is a hot spot?
300
The type of eruption with granitic lava.
What is a quiet eruption?
300
A volcano that is mainly composed of tephra.
What is a cinder cone volcano?
300
When magma squeezes into cracks in rocks bellow the surface.
What are dikes and sills?
400
A fast-moving body of hot gases and solids.
What is pyroclastic flow?
400
An eruption that occurs when magma escapes from narrow and elongated cracks in Earth's crust.
What is a fissure eruption?
400
The type of eruption with basaltic lava.
What is an explosive eruption?
400
The type of volcano that has both quiet and explosive eruptions.
What is a composite volcano?
400
When a volcano stops erupting, magma hardens inside the vent, erosion begins to where away the volcano, and the igneous core is left behind.
What is a volcanic neck?
500
A large, usually circular depression that forms when the top of a volcano collapses and becomes wedged into the nearly empty magma chamber.
What is a caldera?
500
A material's resistance to flow; the inability to flow easily.
What is viscosity?
500
Lava that develops a smooth skin and rope like patterns.
Lava that flows at a lower temperature.
(yes, you must answer both correctly to get the points.)
What is pahoehoe lava?
What is aa lava?
500
The type of volcano with explosive eruptions.
The type of volcano with quiet eruptions.
(yes, you must answer both correctly to get the points.)
What is a cinder cone volcano?
What is a shield volcano?
500
What forms when magma slowly cools and solidifies before it reaches the surface.