Where these collisions occur the results are mountain ranges, (India plate hitting the Asian plate and Mt Everest occurs), volcanos like Mt Etna, and earthquakes id est San Franciso in early 1900s and 1989 and Haiti this past week. It is believed that the convection currents in the core are a result of radiation warming, I guess you could say it is global warming. But not like glover thinks...
It is Bush's fault ...kiddin'
I posted on this subject yesterday. I was saying some scientist should get a grant so they can gin up some "research" linking plate tectonics to global "climate change."