a steep-sloped deposit of solid fragments ejected from a volcano
What is a cinder cone volcano.
100
a block of lithosphere that consists of the crust and the rigid, outermost part of the mantle; also called lithospheric plate
What is a tectonic plate.
100
the point on Earth’s surface directly above an earthquake’s starting point, or focus
What is the epicenter.
100
the hypothesis that states that the continents once formed a single landmass, broke up, and drifted to their present locations
What is continental drift
100
the solid, outer layer of Earth that consists of the crust and the rigid upper part of the mantle
What is lithosphere.
200
the body of molten rock that feeds a volcano
What is magma chamber
200
the boundary between tectonic plates that are colliding
What is a convergent boundary.
200
a break in a body of rock along which one block slides relative to another; a form of brittle strain
What is a fault.
200
the vertical movement of air currents due to temperature variations
What is convection current.
200
the solid, plastic layer of the mantle beneath the lithosphere; made of mantle rock that flows very slowly, which allows tectonic plates to move on top of it
What is asthenosphere
300
an opening at the surface of the Earth through which volcanic material passes
What is a vent.
300
the boundary between two tectonic plates that are moving away from each other
What is a divergent boundary
300
a volcanically active area of Earth's surface, commonly far from a tectonic plate boundary
What is a hotspot.
300
the process by which new oceanic lithosphere (sea floor) forms as magma rises to Earth's surface and solidifies at a mid-ocean ridge
What is sea floor spreading.
300
the "middle sphere"; the strong, lower part of the mantle between the asthenosphere and the outer core
What is the mesosphere.
400
a large, gently sloped volcano that forms by eruptions of basaltic lava flows
What is a shield volcano.
400
the boundary between two tectonic plates that are moving away from each other
What is a transform boundary.
400
a movement or trembling of the ground that is caused by a sudden release of energy when rocks along a fault move
What is an earthquake.
400
the study of earthquakes, including their origin, propagation, energy, and prediction
What is seismology.
400
the elevation of regions of the Earth's crust
What is uplift
500
a volcano made of alternating layers of lava and pyroclastic material; also called stratovolcano
What is a composite volcano.
500
the theory that explains how large pieces of the lithosphere, called plates, move and change shape
What is plate tectonics.
500
an area of deep cracks that forms between two tectonic plates that are pulling away from each other
What is the rift zone.
500
the supercontinent that formed 300 million years ago and that began to break up 250 million years ago