The rock and sediment there had a similar composition to the iridium layers, and the scientists suggested the depression, called the Chicxulub crater, was caused by the impact of an asteroid. Researchers believe the other anomalies spotted across the globe were caused by scattering debris when the...
continent, which he calledPangea, and the breakup of this continent heralded Earth’s current continental configuration as the continent-sized parts began to move away from one another. (Scientists discovered later that Pangea fragmented early in theJurassic Period.) Wegener presented the idea of ...