Every Tyrannosaurus rex you've seen came from Hell Creek. Hell Creek Formation preserves the last 700,000 years of the Cretaceous, a stretch of Late Maastrichtian badlands across Montana and the Dakotas. T. rex, Triceratops, Edmontosaurus, Ankylosaurus, Pachycephalosaurus, Thescelosaurus, Anzu wyliei, and Dakotaraptor all lived here. Directly above the formation sits the K-Pg boundary, a thin band of clay enriched in iridium, deposited in the aftermath of the Chicxulub impact. Art: Franz Anthony. Hell Creek in the shop. fossi.ls/HcRk8T














