Plumbing the Depths of the Kimmeridge Clay

Although the Kimmeridge Clay is one of the most highly studied of the World’s hydrocarbon source rocks, over the past 100 years its macrofossils have been somewhat neglected. In fact, the Kimmeridge Clay Formation was once described as the ‘least interesting suite of rocks’ to collect from for palaeontologists studying the Jurassic Period. Dorset, home to the complete Jurassic succession, is a mecca for fossil collectors and many of the major national natural history museums contain material collected from this area. But 35 years ago, when Steve Etches first began collecting from the Late Jurassic Kimmeridge Clay, he soon realised that these strata had been underexplored, underrepresented and specimens had been poorly documented and recorded. His great journey began.

Kimmeridge Bay, East and West, has the finest suite of Kimmeridge Clay rocks anywhere in the world and the Upper Kimmeridge Clay succession has been assigned the International Type Section for these strata. The bay lies along one of the most remote areas of the Dorset Coast. Access may only be made at beach level within Kimmeridge Bay itself, and for 2.5 miles to the east, sections of the beach are cut off at high tide by sheer cliffs and steep headlands. West of Kimmeridge Bay, the coastline falls within the MOD ranges and access is restricted much of the time by live fire practise. There is no vehicular access and the logistics of collecting along this section are difficult and dangerous. For all these reasons, it was apparent to Steve, that collecting from this locality had not previously been carried out in a scientific, ordered, bed by bed manner. He made the decision to collect from these strata exclusively, to fill this palaeontological void.

Steve’s talk focuses on the diversity of his collection: the stunning specimens, with many world firsts and specimens still undescribed, and their scientific importance. And, more importantly, the stories around the finds, their painstaking extraction and preparation, to reveal the secrets of these amazing fossils, how they lived, bred and died in the seas of Kimmeridge, 157 million years ago.