On Sunday 1st October, UKAFH ventured along the coastline of Seaford in East Sussex – a small town about 10 miles east of Brighton with towering white cliffs.
After a very fortunate summer meteorologically speaking, we had spent the week with a close eye on the remanence of hurricane Marie which crossed the Atlantic and now threatened our fossil hunt.
Fortune persisted however, as although a bit windy and the sea choppy, we began the day dry and mild.
We began with an in depth talk about the geology by UKAFH leader Daniel Slidel. Exposed in the towering white cliffs of Seaford is the Upper Chalk, a Cretaceous deposit (Santonian-Campanian) about 86-83 million years old. Formed from the tiny platelets of coccolithophores – phytoplankton that was abundant in the deep, warm sea that existed here. This striking sediment helped preserve the creatures dwelling on the sea floor, which included bivalves, sponges, corals, bryozoan and the echinoids (sea urchins) this stretch of coastline is famous for. Within the cliffs are horizontal bands of flints which are visible as far as the horizon allows.
After a short walk from the car park we descended some concrete steps onto the beach. The abundance of fossil echinoids was immediately noted as within the exposed bedrock on the foreshore were the tell-tale circular marks of weathered echinoids in situ. We could not extract these as the bedrock here is protected, however this gave us ambition as we traveled west towards loose boulders from which we could extract specimens. It was not long before beautiful echinoids were being found loose or extracted from boulders. There were two genre found, Echinocorys and Micraster. These were found in chalk boulders preserved with delicately thin calcite test – however the flints on the foreshore should not be overlooked either as more robust and often sea rolled specimens for found here too. Other finds on the day included small bivalves, shapely sponges, coral and bryozoan.
As the afternoon drew late the atmosphere became heavy with the approaching storm and the first rain fell as we ascended the concrete steps back to the car park. Looks like we did it again and avoided the worst of the weather!
Thank you to everyone who attended this fossil hunt. It really was a great and friendly group of people, it was a pleasure to guide you through the Cretaceous geological history of Seaford.
Hampton, M.J., H.W. Bailey, L.T. Gallagher, R.N. Mortimore and C.J. Wood 2007. The biostratigraphy of Seaford Head, Sussex, southern England; an international reference section for the basal boundaries for the Santonian and Campanian Stages in chalk facies. Cretaceous Research, v. 28, no. 1, p. 46-60.