Chapter 3 Vocab Flashcards
A weak spot in the crust where magma has come to the surface.
Volcano
The molten mixture of rock-forming substances,gases,and water from the mantle
Magma
Liquid magma that reaches the surface; also the rock formed when liquid lava hardens
Lava
A major belt of volcanoes that rims the Pacific Ocean
Ring of fire
A string of islands formed by the volcanoes along a deep ocean trench.
Island arc
An area where magma from deep within the mantle melts through the crust above it
Hot spot
The pocket beneath a volcano where magma collects
Magma Chamber
A long tube through which magma moves from the magma chamber to earths surface
Pipe
The opening through which molten rock and gas leave a volcano
Vent
The area covered by lava as it lies out of a volcano’s vent
Lava flow
A bowl-shaped area that forms around a volcano’s central opening
Crater
A material that is formed from the elements oxygen and silicon; Silica is found in magma.
Silica
A hot, fast-moving type of lave that gardens to form smooth, ropelike coils.
Pahoehoe
A slow-moving type of lace that hardens to form rough chunks; cooler than pahoehoe
AA
The expulsion of ash, cinders, bombs, and gases during an explosive volcanic eruption.
Pyroclastic flow
Said of a volcano that is erupting or has shown signs of erupting in the near future
Active
Said of a volcano that does not show signs of erupting in the near future.
Dormant
Said of a volcano that is unlikely to erupt again
Extinct
A pool formed by groundwater that has risen to the surface after being heated by a nearby body of magma
Hot spring
A fountain of water and steam that builds up pressure underground and erupts at regular intervals
Geyser
Energy from water or steam that has been heated by magma
Geothermal Energy
A wide, gently sloping mountain made of layers of lava and formed by quiet eruptions
Shield Volcano
A steep, cone-shaped hill or mountain made of volcanic ash,Cinders,and bombs piled up around a volcano’s opening
Cinder Cone
A tall, cone-shaped mountain in which layers of lava alternate with layers of ash and other volcanic materials
Composite Volcano
The large hole at the top of a volcano’s magma chamber collapses
Caldera
A deposit of hardened magma in a volcano’s pipe
Volcanic Neck
A slab of volcanic rock formed when magma forces itself across rock layers
Dike
A slab of volcanic rock formed when magma squeezed between layers of rock
Sill
A mass of rock formed when a a large body of magma cooled inside the crust
Batholith
