|MadSci Network: Earth Sciences|
The object that impacted Earth and possibly caused the extinction of the dinosaurs could not be the cause of the break up of the continents or shifting of polar ice caps.
According to plate tectonic theory, the continents broke apart from Pangea, the original supercontinent, about 200 million years ago. The dinosaur extinction event occurred about 65 million years ago. Regardless of the time difference, the mechanism that drives plate tectonics is thought to be convection currents within the mantle of Earth, not an external or surficial source.
Climatic changes after the impact could have caused changes in the thickness of the polar ice caps, but the impact itself probably had no effect.
Rick De Van
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