Series: Chaco Collections—Paleontology

The fossils at Chaco represent ten to fifteen million years of life on Earth, during the Late Cretaceous when New Mexico sat on the ever-changing coastline of an inland sea. This ocean, known as the Western Interior Seaway, was home to sharks and giant reptilian predators like mosasaurs and plesiosaurs, as well as ammonites, relatives of today’s squids. NPS scientists used imaging techniques to create virtual 3D models of a few of the park’s paleontological treasures.