Download Plate Tectonics Vocabulary

Plate Tectonics Vocabulary
1. Continental drift- the hypothesis that a single large landmass broke up into smaller
landmasses to form the continents, which then drifted to their present locations; the
movement of continents
2. Plate tectonics- the theory that Earth’s outer layer is made up of large, moving pieces
called tectonic plates; the theory explains how plates interact and how those interactions
relate to processes such as earthquakes and mountain building
3. Theory- a system of ides that explains many related observations and is supported by a
large body of evidence acquired through scientific investigation
4. Sea-floor spreading- the process by which new oceanic lithosphere (sea floor) forms when
magma rises to Earth’s surface at mid-ocean ridges and solidifies, as older, existing sea
floor moves away from the ridge.
5. Subduction- the process by which one lithospheric plate moves beneath another palte as a
result of tectonic forces
6. Magnetic reversal- the process by which Earth’s magnetic north pe and magnetic south
pole switch positions periodically; a change in the direction in which Earth’s magnetic field
points
7. Lithosphere- the solid, out layer of Earth that consists of the crust and the rigid upper part
of the mantle
8. Asthenosphere- the soft layer of the mantle on which the tectonic plates move
9. Tectonic plate- a block of lithosphere that consists of the crust and the rigid, outermost
part of the mantle
10. Deformation- the bending, tilting, and breaking of Earth’s crust; the change in the shape of
rock in response to stress
11. Convergent boundary- the boundary between tectonic plates that are colliding
12. Divergent boundary- the boundary between two tectonic plates that are moving away
from each other
13. Transform boundary- the boundary between tectonic plates that are sliding peas each
other horizontally