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Chapter 7 - Vocab
Chapter 7 - Vocab - Plate techtonics
Term | Definition |
---|---|
Pangaea | A super continent that today's continents were once a part of. |
Continental drift | A hypothesis which suggests that continents are in constant motion on the surface of the Earth. |
Mid-ocean ridges | The mountain ranges in the middle of the oceans. |
Seafloor spreading | The process by which new oceanic crust forms along a mid-ocean ridge and older oceanic crust moves away from the ridge. |
Normal polarity | A state in which, magnetized objects, such as compass needles, will orient themselves to point north. |
Magnetic reversal | An event when the magnetic field reverses direction. |
Reversed polarity | A state in which, magnetized objects would reverse direction, orient themselves to point south. |
Plate tectonics | Rigid slabs of rock, or plates, that move with respect to each other that make up the Earth's surface |
Lithosphere | The cold and rigid outermost rock layer. |
Divergent plate boundary | An area which forms where two plates separate. |
Transform plate boundary | An area which forms where two plates slide past each other. |
Convergent plate boundaries | An area which forms where two plates collide |
Subduction | The process which a denser plate sinks below a more buoyant plate. |
Convection | The circulation of material caused by differences in temperature and density. |
Ridge push | The force that moves lithosphere in opposite directions away from the mid-ocean ridge. |
Slab pull | The force that pulls on the rest of the plate as a slab sinks. |