Cretaceous–Paleogene boundary Cretaceous–Paleogene boundary The Cretaceous–Paleogene (K–Pg) boundary, formerly known as the Cretaceous–Tertiary (K-T) boundary, is a geological signature, usually a thin band of rock. "K", the first letter of the German word "Kreide" (chalk), is the traditional abbreviation for the Cretaceous Period and "Pg" is the abbreviation for the Paleogene Period. The K–Pg boundary marks the end of the Cretaceous Period, the last period of the Mesozoic Era, and marks the beginning of the Paleogene Period, the first period of the Cenozoic Era. Its age is usually estimated at around 66 Ma (million years ago), with radiometric dating yielding a more
Eldon George as a sparrow or robin. In 1986, a scientific team that included Paul Olsen, discovered hundreds of thousands of fossils at Wasson Bluff, one of the biggest troves ever found. Fossil discoveries on the Fundy shoreline are especially significant because they date from 200 million years ago, the boundary between the Triassic and Jurassic geological periods, when about half of the Earth's living creatures suddenly became extinct giving rise to dinosaurs and the mammals that eventually succeeded them. Many of the fossils that date from that time remain hidden, buried under North American forests, farmland or cities. But, the Fundy