Amphibian footprints from the mid-Carboniferous of Northumberland, England: Sedimentological context, preservation and significance

A trackway and footprints produced by a large amphibian have been discovered in Namurian strata on the coast of Northumberland, near Howick, in northeastern England. They occur on a thin layer of mud upon the surface of a sandstone bed deposited by a small delta on a coastal plain. They were preserved by subsequent deposition of a thin sandstone from the flooding of a nearby channel. Abandonment of the area led to the growth of plants and the formation of a thin coal seam, so that the footprint sandstone was rootleted to form a seatearth. The Howick footprints average 18 cm in length and 14 cm in width. The trackway is poorly preserved and appears to consist of at least five footprints arranged either side of a groove 0.19 m in width which is interpreted as a body drag trace. The external trackway width is 0.7 m, and the stride is 1.4 m. diemont Bay 3 km south of Howick Bay, more footprints occur of about the same size, but also poorly preserved, upon the surface of a fluvial sandstone. footprints are some of the earliest occurring in Carboniferous strata in Europe. Although preservation of both sets of footprints is now poor, the Howick footprints can be compared to the ichnogenus Baropezia.