UKAFH

Fossil Hunt at Caistor Quarry 1st July 2017

Posted on July 20, 2017 Updated on July 18, 2017

On the 1^st July, UKAFH members met at Caistor Quarry in Caistor st Edmund, a village just south of Norwich in Norfolk.

The quarry produces over 19,000 tonnes of ground chalk, lump chalk and flint per annum. Sand derived from the Norwich Crag and Pleistocene gravels are also commercially extracted from the surface before the extraction of chalk begins. However, our interest here was firmly in the chalk. The chalk forms part of the Beeston Chalk Member, some of the earliest chalk exposed in the UK of Late Campanian age about 80 million years old. Importantly, this chalk member is not exposed on the UK coastline and so access to it can only be achieved via inland sites such as Caistor Quarry. The chalk formed at the bottom of a warm, relatively deep sea that was inhabited by great numbers of microscopic coccolithophores – tiny phytoplankton whose tiny calcite platelets, called coccoliths, formed the striking white calcium carbonate sediment. Fortunately for us the Beeston Chalk Member is particularly fossiliferous with belemnites, brachiopods, echinoids and fish remains being frequently found.

We began with a geological explanation and description of likely finds provided by Sam Caethoven before heading into the quarry. The quarry was in operation during our visit so it was vital we kept away from the large machinery and remained as a group throughout the hunt, however there was a huge expanse of quarry walls and scree piles to explore and the quarry had kindly provided a large amount of fresh material for us to search through.

We were in many ways lucky with the weather, a beautiful warm and Sunday Norfolk day, however within the quarry we were very exposed so plenty of water and sunscreen was essential and the bright sunshine reflecting off the bright white chalk was glaring, making it harder to spot fossils than would otherwise be the case. That said, there was no shortage of great finds.

The finds began with a lovely partial echinoid found by Adam Taylor before many superb Echinocorys echinoid specimens were found by David Clark, Sam Caethoven, Susan Harley, Mary Bite and James Hewitt. Other interesting finds included fish remains found by Martin Beever who also found some very lovely crinoid stems; Poppy Hewitt discovered a lovely Ventriculites sponge preserved in flint; Aidan Philpott found a partial shark tooth and plenty of belemnites and brachiopods were also found among the group.

It was a glorious day to be out fossiling even though it was a bit glaring at times. Thank you to the awesome group who attended and a huge thank you goes to Needham Chalks Ltd who let us investigate their quarry.