Eric Walker added The Day the Dinosaurs Died | The New Yorker to Cretaceous–Paleogene boundary, Paleontology and Hell Creek Formation

Eric Walker added Hell Creek Formation - Wikipedia to Hell Creek Formation

Eric Walker added a number of topics and a number of links to Geology, and added Geology to Science, engineering, mathematics and the humanities

Eric Walker added The Day the Dinosaurs Died | The New Yorker and Hell Creek Formation - Wikipedia to Hell Creek Formation, and added Hell Creek Formation to Geology