| A | B |
|---|
| The molten mixture of rock forming substances, gases, and water deep in Earth's mantle. | magma |
| The block of rock that forms the lower half of a fault. | footwall |
| The measure of how much mass there is in a volume of a substance. | density |
| A type of seismic wave that moves the ground up and down or side to side. | Secondary Wave |
| The supercontinent that began to break apart 250 million years ago. | Pangaea |
| The type of earthquake wave that compresses and expands the ground. | Primary |
| The point on the earth's surface directly above an earthquake's focus. | epicenter |
| An earthquake that occurs after a larger earthquake in the same area. | aftershock |
| A mass of rock formed when a large body of magma cooled inside the crust. | batholith (25) |
| The large hole at the top of a volcano formed when the roof of a volcano's magma chamber collapses. | caldera (29) |
| A steep, cones-shaped hill or mountain made of volcanic ash, cinders, and bombs piled up around a volcano's opening. | cinder cone (15) |
| A tall, cone-shaped mountain in which layers of lava alternate with layers of ash and othe volcanic materials. | composite volcano (16) |
| A force that builds up mountains and landmasses on Earth's surface. | constructive force |
| The hypothesis that the continents slowly move across Earth's surface and were once all joined together to form a supercontinent called Pangaea. | continental drift |
| A plate boundary where two plates move toward eachother. | convergent boundary. |
| A force that slowly wears away mountains and other features on the surface of the Earth. | destructive force |
| A plate boundary where two plates move away from eachother. | divergent boundary |
| A break in the earth's crust where slabs of rock slip past eachother. | fault |
| The point beneath earth's surface where rock breaks under stress and causes an earthquake. | focus |
| The block of rock that forms the upper half of a fault. | hanging wall |
| An area where magma from deep within the mantle melts through the crust above it. | hot spot (27) |
| A string of islands formed by the volcanoes along a deep ocean trench. | island arc (28) |
| The measurement of an earthquake's strength based on seismis waves and movement along faults. | magnitude |
| A scale that rates earthquakes according to their intensity and how much damage they cause. | Mercalli Scale |
| a type of fault where the hanging wall slides downward; caused by tension in the crust. | normal fault |
| The name of the single landmass that broke apart approximately 250 million years ago. | Pangaea |
| The Theory that pieces of Earth's lithosphere are in constant motion, driven by convection currents in the mantle. | Plate Tectonics |
| The expulsion of ash, cinders, bombs, and gases during an explosive volcanic eruption. | pyroclastic flow (18) |
| A type of fault where the hanging wall slides upward. | reverse fault |
| A scale that rates seismic waves as measured by a particular type of mechanical seismograph. | Richter Scale |
| A deep valley that forms when two plates move away from eachother. | rift valley |
| A major belt of volcanoes that rims the Pacific Ocean. | Ring of Fire |
| The process by which molten material adds new oceanic crust to the ocean floor. | sea-floor spreading |
| A vibration that travels through Earth carrying the energy released during an earthquake. | seismic wave |
| A device that records ground movements caused by seismic waves as they move through Earth. | seismograph |
| A wide, gently sloping mountain made of layers of lava formed by quiet eruptions. | shield volcano (14) |
| A material that is formed from the elements oxygen and silicon; found in magma | silica (13) |
| A slab of volcanic rock formed when magma squeezes between layers of rock. | sill (23) |
| Type of fault where rocks on either side move past eachother sideways with little up-or-down motion. | strike-slip fault |
| The process by which oceanic crust sinks beneath a deep-ocean trench and back into the mantle at a convergent boundary. | subduction |
| A downward fold in rock formed by compression in Earth's crust. | syncline |
| A plate boundary where two plates move past eachother in opposite directions. | transform boundary |
| A weak spot in the crust where magma has come to the surface. | volcano (4) |
| A large wave produced by an earthquake on the ocean floor. | tsunami |
| The build up of new landforms | volcanism (1) |
| The movement of magma from the interior of the eath to the surface. | extrusive (2) |
| The movement of magma between rock layers that are below the surface of the earth. | intrusive (3) |
| Mound formed from the acculmulation of volcanic materials. | volcanic cone (5) |
| A round, cup-shaped opening in the cone of a volcano. | crater (10) |
| A crack in the side wall of a volcano. | fissure (17) |
| A volcano that has erupted in recent times (approx. past 100 years). | active volcano (20) |
| A volcano that may show signs of activity, but has not erupted in recent times. | dormant volcano (21) |
| A volcano that has not erupted since recorded history and does not seem capable of erupting again. | extinct volcano (22) |
| Energy from water or steam that has been heated by magma. | geothermal energy (26) |
| The pocket beneath a volcano where magma collects. | magma chamber (6) |
| A long tube through which magma moves from the magma chamber to Earth's surface. | pipe (7) |
| The opening through which molten rock and gas leave a volcano. | vent (8) |
| The area covered by lava as it pours out of a volcano's vent. | lava flow (9) |
| Liquid magma that reaches the surface. | lava (12) |
| The resistance of a liquid to flowing. | viscosity (19) |
| A slab of volcanic rock formed when magma forces itself across layers. | dike (24) |
