convection currents: the upward movement of warm air and the downward movement of cool air. as this cycle happens with magma, it pushes against the continental plates causing them to move

sea floor spreading Occurs at mid-ocean ridges where new crust is formed and makes the ocean bigger which causes deep sea trenches from this new crust subduction under a land continent.

geomagnetism:as magma cools, the iron in it points to where the magnetic pole was at the time, because the magnetic pole changes. until the rock is completely cool, the iron can still move. by comparing iron in rocks we can see how old they are.

mid ocean ridges:when two continents diverge they cause a rift where lava flows out and creates land.