The geology of the Folkestone area can best be understood when viewed within the broader context of the structural pattern of South-east England. This whole region is composed mainly of the rocks of the Secondary era (Jurassic and Cretaceous) overlying a deep Palaeozoic platform, but the surface geology is essentially concerned with the younger Cretaceous rocks, a sequence of the component formations being easily identifiable in the vicinity of Folkestone.
The Leas Cliff at Folkestone is unstable and in 1784 suffered a major landslip which led to a deposit at sea level which was levelled to begin a form of sea defence. On this narrow stretch there has been a toll road and switchback railway but continued erosion caused both to close. A zig zag path was built into the cliff face for the benefit of local residents and visitors:
To prevent further erosion and flooding new sea defence work began in 2004 at a cost of £12m. This comprised building a new rocky headland and three groynes. With your back to the notice board and facing the sea, observe the shape of these new features.
At GZ you will find a notice board that describes the restoration work and the creation of a country park on this Lower Leas area. In order to claim this earthcache you will need to look at that notice board and do some online research. Please answer the following:
What rocks form the Younger Cretaceous Period?
Describe the shape of the groynes and explain how, along with the rocky headland, they will help prevent further landslips and flooding.
Which country provided the rock used in the creation of these?
Now climb the zig zag path to the top of The Leas to another notice board (Stage 2) and answer these questions:
What name is given to the rock that created the zig-zag path that also forms the caves and allows the path to bind itself to the Cliff face?
What is the height of the cliffs at this point?
Any photos you may wish to upload would be appreciated.