It marked the end of the Cretaceous Period, and with it the Mesozoic era, while heralding the beginning of the Cenozoic era, which continues to this day. Most other tetrapods weighing more than 25 kilograms (55 pounds) also became extinct, with the exception of some ectothermic species such as sea turtles and crocodilians. The event caused the extinction of all non-avian dinosaurs. The Cretaceous–Paleogene ( K–Pg) extinction event, also known as the Cretaceous–Tertiary ( K–T) extinction, was a sudden mass extinction of three-quarters of the plant and animal species on Earth, approximately 66 million years ago. ![]() Complex Cretaceous–Paleogene clay layer (gray) in the Geulhemmergroeve tunnels near Geulhem, The Netherlands (finger is below the actual Cretaceous–Paleogene boundary).Picture taken at the San Diego Natural History Museum Wyoming rock with an intermediate claystone layer that contains 1,000 times more iridium than the upper and lower layers.Badlands near Drumheller, Alberta, where erosion has exposed the K–Pg boundary.Bali Khila, an eroded hill from the Deccan Traps, which are another hypothesized cause of the K–Pg extinction event. ![]() Such an impact can release the equivalent energy of several million nuclear weapons detonating simultaneously Artist's rendering of an asteroid a few kilometers across colliding with the Earth. ![]() Image description from the top to bottom:
0 Comments
Leave a Reply. |
AuthorWrite something about yourself. No need to be fancy, just an overview. ArchivesCategories |