Well, the plate tectonics are under us, under the continents, under the ocean floor. They are what cause earthquakes, tsunamis, etc. If there are any further questions just ask. I hope I helped!
But plate tectonics is the theory which suggests that the Earth's crust is made up of solid plates moving relative to each other. Plate tectonics and the plate tectonics theory aren't really two...
This theory suggests that large, jigsaw like pieces of rock float on the upper mantle. It suggests that they fit together all over the planet, and are moving, though slowly at times. This theory was...