Thirty eight members of Crewkerne & District U3A’s Geology group went to Lulworth Cove for their last field trip of 2019. For some long-standing members it was a return visit, as they had previously visited the World Heritage Site 14 years ago. The geology group were met by two Jurassic Heritage Coast Rangers, who gave them an informative talk in the education room of the Visitor Centre. Members were shown how the Jurassic rocks along that section of the coast were originally formed and then compressed, folded and eroded, to produce the formation seen today. Regarded as one of the finest coves in the world, it was formed over the last few thousand years and while the Cretaceous chalk was perma-frosted, a river flowed over it and cut through through the resistant bands of near vertical Purbeck and Portland limestones on its way to the sea, which at the time was further away and at a much lower level.
Today’s higher sea level has exploited the narrow gap formed in the hard rocks and eroded the softer Wealden clays and sandstones behind, hollowing out the almost circular cove. After the talk, the Rangers split the party into two groups and led them to the Stair Hole and the beach, where they were able to see the effects of the erosion that is still being made today by the sea. Those who had visited Lulworth Cove over a decade ago, noticed that several features, including the cliff path behind the cove, had been lost to erosion in recent years. Geology group member Liz Randall said: “The weather was gloomy and chilly but thankfully the torrential rain that was forecast held off until the coach door closed for our homeward journey.”