Dinosaur footprints from the Lower Cretaceous of northern Spain: their sedimentological and palaeoecological context
Abstract Dinosaur footprints are described from two distinct horizons within the Lower Cretaceous sequence of the western Cameros Basin (Province of Burgos, Northern Spain). Footprints from a series of lacustrine carbonates in the Berriasian Rupelo Formation show a rounded outline and are preserved as negative endichnia. These footprints were probably formed by a bipedal ornithopod herbivore. Sauropod bones occur at a similar stratigraphic horizon at other localities in the basin. The footprints support the sedimentological evidence that the lake was shallow, with vegetated margins subject to frequent exposure. Tridactyl footprints, unusually preserved as positive epichnia, form a trackway on a sandstone bedding surface within the Piedrahita de Muno Formation (? Valanginian-Barremian). This set of footprints was probably made by a bipedal theropod carnivore which inhabited an extensive floodplain environment. The alternation of sandstones and overbank mudstones facilitated preservation of this set of footprints.