Detailed stratigraphy of the uppermost Kimmeridge Clay Formation (Upper Jurassic) from the Swanworth Boreholes, Dorset, UK

The higher parts of the cores of the Swanworth Boreholes, Dorset, allow detailed investigation of parts of the Upper Jurassic Kimmeridge Clay Formation that are difficult to sample on the coastal type-section. The member-level divisions set up by Buckman and Arkell are confirmed as readily recognisable. Body-fossils have been found throughout the beds examined and are recorded and confirm the ammonite zonal boundaries as proposed by Cope (1978). The extensive bioturbation of the sediments in the highest beds was primarily caused by decapod crustaceans whose remains are preserved in the borehole cores. Detailed examination of the cores has failed to confirm the existence of the so-called Chapmanʹs Pool Pebble Bed, nor can its existence at nearby Gad Cliff be confirmed.