Triassic vertebrate footprints from the Sherwood Sandstone Group, Hilbre, Wirral, northwest England

Abstract

Fossil vertebrate footprints of Triassic age are reported, described and identified from Hilbre, a tidal island lying 1.6 km (1 mile) off West Kirby, Wirral, northwest England. The finds represent the most complete in situ vertebrate footprint assemblage from the Lower-Middle Triassic of the British Isles found in the last 80 years. Traditionally, the rocks exposed on Hilbre have been assigned, as part of the Cheshire Basin, to the Chester Pebble Bed Formation (formerly Bunter Pebble Beds) of the Lower Triassic. Evaluation of the footprint assemblage and the sedimentology of the beds tests and generally supports the recent hypothesis of the British Geological Survey that the exposures on Hilbre should be reassigned to the Ormskirk Sandstone Formation (Middle Triassic) within the East Deemster sub-basin (part of the East Irish Sea Basin).