Across
- 7. The sinking of oceanic lithosphere beneath overriding oceanic or continental lithosphere at a convergent plate boundary.
- 8. A divergent boundary marked by a rift at the crest of a mid-oceanic ridge, where new oceanic crust is formed by seafloor spreading.
- 10. The velocity at which one lithospheric plate moves relative to another.
- 14. The large-scale movements of continents across Earth's surface driven by the plate tectonic system.
- 15. A contour that connects rock of equal age.
- 16. A boundary between lithospheric plates where two plates move apart and new lithosphere is created.
- 17. A chain of volcanic islands formed on the overriding plate at a convergent boundary by magma that rises from the mantle as water released from the subducting lithospheric slab causes fluid-induced melting.
- 18. A narrow, cylindrical jet of hot solid material rising from deep within the mantle, thought to be responsible for intraplate volcanism.
Down
- 1. The mechanism by which new oceanic crust is formed at a spreading center on the crest of a mid-ocean ridge. As two plates move apart, magma wells up in to the rift between them to form new crust, which spreads laterally away from the rift and is replaced continually by newer crust.
- 2. An undersea mountain chain at a divergent boundary, characterized by earthquakes, volcanism, and rifting, all caused by the tensional forces of mantle convection that are pulling the two plates apart.
- 3. One in a pattern of long, narrow bands of high or low magnetic intensity on the seafloor that are parallel to and almost perfectly symmetrical with respect to the crest of a mid-ocean ridge.
- 4. A plate boundary at which the plates slide horizontally past each other and lithosphere is neither created nor destroyed.
- 5. The science of measuring the shape of Earth and locating points on its surface.
- 6. A supercontinent that coalesced in the late Paleozoic era and comprised all present continents, then began to break up in the Mesozoic era.
- 9. The theory that describes and explains the creation and destruction of Earth's lithospheric plates and their movement over Earth's surface.
- 11. A supercontinent older than Pangaea that formed about 1.1 billion years ago and began to break up about 750 million years ago.
- 12. A boundary between lithospheric plates where the plates move toward each other and one plate is recycled into the mantle.
- 13. The detailed history of Earth's magnetic field reversals as determined by measuring the the thermoremanent magnetization of rock samples whose ages are known,