nixon source 1: \dinosaur extinction\ by jame...
nixon source 1: \dinosaur extinction\ by james zann one of earths greatest mysteries is the mass extinction of the dinosaurs that occurred at the end of the cretaceous period. while there is still much debate, some scientists believe the event was caused by the impact made from a huge asteroid hitting earth in the yucatan peninsula of mexico. the asteroid created a 10 - mile - wide crater called chicxulub that was discovered in 1970 by researcher glen penfield. he believes the chicxulub crater was formed by the same asteroid that likely killed the dinosaurs. the asteroid is estimated to have been six miles wide and thought to have impacted with the power of 100 tons of dynamite, making it a billion times more powerful than an atom bomb. the student found information from other sources. select two pieces of evidence that support the claim of the author of source 1. a thin clay layer has been discovered in chicxulub and many parts of the world revealing the presence of the element, iridium, which is typically only found in solar system materials like asteroids. a paleontologist from texas tech university says that a 310 - mile - wide crater discovered in shiva, india, is evidence of an asteroid collision that could have caused the mass extinction. a father and son scientist team did research that led them to believe that an asteroid was the cause of the extinction of the dinosaurs before the chicxulub crater was discovered.