Who is Alfred Wagner?
A German scientist who published a book proposing that the continents had been connected as a single body of land earlier in Earth’s history.
What does the model of plate tectonics explain and how does the process work?
How the continents and the ocean floor could move; earth's surface is in pieces called plates.
What is seafloor spreading? How is related to Wagner's idea?
Magma enters cracks in seafloor plates, forces them apart, cools and hardens; supports Wagner's theory.
Where in the world do divergent boundaries occur?
Locations where plates move apart.
What are convergent boundaries and what happens there?
Locations where plates collide.
How does subduction work?
One colliding plate carries part of an ocean floor, and the other carries part of a continent, then the oceanic plate slides under the continental plate.
How does an ocean trench form?
When plates move toward each other on the ocean floor, one plate sinks under the other.
If a continental valley begins to widen, what conclusion might you draw about the region’s plate movement? Why?
Wow, you really know your stuff! / Sorry, we were looking for...
How do earthquakes occur at a transform boundary?
Strain on the rock builds up along transform boundaries and then is quickly released.
Where would it be easiest to drill through Earth’s crust and reach the mantle? Why?
The thinnest oceanic crust is found at mid-ocean, underwater mountain ranges where tectonic plates are diverging, and new oceanic crust is formed.
