Continental Drift
Earth’s ancient supercontinent
What is Pangea?
Huge pieces of crust and rigid upper mantle that fit together at their edges to cover Earth’s surface
What are tectonic plates?
A volcano with broad, gently sloping sides and a nearly circular base, formed by slow flowing lava
What is a shield volcano?
Variation in elevation of Earth’s crust
What is topography?
Sensitive instrument that can detect seismic waves, even at great distances
What is a seismometer?
A hypothesis that proposes that Earth’s continents had once been joined as a single landmass
What is Continental Drift?
Regions where two tectonic plates are moving apart
What are divergent boundaries?
Volcano which forms as material falls back to Earth and piles up around the vent
What is a cinder cone volcano?
When a whole region is uplifted, a relatively flat top is formed
What is a plateau?
Any fracture or system of fractures along which Earth moves
What is a fault?
The rock layers of the Appalachian Mountains match layers from mountains in Europe and this other region
What is Greenland?
When two tectonic plates move toward one another
What are convergent boundaries?
A volcano which is formed of layers of ash and hardened chunks of lava from violent eruptions, the largest volcano type
What is a composite volcano?
Form when large regions of Earth have been slowly forced upward
What are uplifted mountains?
The vibrations of the ground produced during an earthquake
What are seismic waves?
This plant can be found on at least 5 continents and is evidence of continental drift
What is glossopteris?
A region where two plates slide past each other horizontally
What are transform boundaries?
Large volcanic crater
What is a caldera?
Form between large faults when pieces of crust are dropped downward due to tensional forces
What are fault-block mountains?
The point on Earth’s surface directly above the focus
What is the epicenter?
The name of the scientist to first propose the idea that continents were drifting
Who is Alfred Wegener?
When the denser plate descends below the other
What is subduction?
Unusually hot regions of Earth’s mantle where high-temperature plumes of magma rise to the surface.
What are hot spots?
A condition of equilibrium due to the displacement of the mantle by Earth’s continental and oceanic crust
What is isostasy?
This is the intensity of the earthquake, which rates the damage
What is the Modified Mercalli Scale?