A deep underwater valley
What is a trench?
The scientist who discovered the theory of continental drift
Who is Alfred Wegener?
The type of boundary where two plates move away from each other
What is a divergent boundary?
Mountains, such as Mount Everest, may still do this just a little each year
What is grow?
This is the force that creates the convection currents that cause the plates to move
What is heat?
Mountain chain that is formed on ocean floor where plates pull apart
What is an oceanic ridge?
The scientist who discovered the theory of seafloor spreading
Who is Harry Hess?
The type of boundary where two plates move toward each other
What is a convergent boundary?
The place in tectonic plates where most mountain ranges can be found
What is at the edge or boundary?
This is the type of boundary where crust is neither created nor destroyed
What is transform?
The process of one tectonic plate being pushed under another
What is subduction?
Large sections of the crust that move and float on the asthenosphere
What are tectonic plates?
The type of boundary where two plates slide past each other
What is a transform boundary?
The type of mountain that form at converging boundaries
What is folded mountains?
This is the theory that says that the continents float on the asthenosphere, much like an iceberg floats on water
What is isostasy?
A break or fracture in earth's crust, along which rocks move
What is a fault?
Greek for "all lands," the supercontinent believed to have been all together in one landmass
What is Pangaea?
The type of boundary where mid-oceanic ridges and rift valleys are formed
What is a divergent boundary?
The type of mountains that form at divergent boundaries
What is fault-block mountains?
Evidence that supports this theory include mountain ranges lining up on continents when pieced together, fossils that show the same animals and plants occurred on the now separated continents, and scratches on rocks made from glaciers in places with mild climates today
What is continental drift?
The process by which new crust is formed at an oceanic ridge
What is seafloor spreading?
The type of boundary where seafloor spreading occurs and new crust is made
What is divergent?
The type of boundary where earthquakes frequently occur and metamorphic rock is formed
What is a transform boundary?
The type of boundary where mountain chains, island arcs, and deep-ocean trenches are usually found
What is a convergent boundary?
Evidence that supports this theory includes molten material shaped like pillows that form when magma erupts and hardens quickly, magnetic stripes showing that earth's magnetic field has reversed and drilling samples that reveal that the farther from a ridge the rocks were taken, the older they were
What is seafloor spreading?